Xibrar^e OF THE IRew ^ov\{ State IDetcrinan^ College ^Ijf^ f^" ^^0(5^ Cornell University Library SF 996.G7L63 The grouse In health and in disease, bein 3 1924 000 093 371 Cornell University Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924000093371 THE GROUSE IN HEALTH AND IN DISEASE With 21 full-page plates, mostly in colour, and numerous ie.rt illustrations. Frontispiece. (p.z.s. 1910. PI. ixxvin?) \ \ Andre & Sleigh, Ltd. PAIR OF RED GROUSE IN SUMMER WITH YOUNG CHICKS. THE GROUSE IN HEALTH AND IN DISEASE BEING THE POPULAR EDITION OF THE REPORT OF THE COMMITTEE OF INQUIRY ON GROUSE DISEASE EDITED BY A. S. LESLIE SI-XRETARY OF THK CtlMMITTKE ASSISTED BY A. E. SHIPLEY, F.R.S. MASTER OK CHRIST'S COLLEGE, CAMBRIDGE LONDON SMITH, ELDER & CO., 15 WATERLOO PLACE 1912 [A// rights reservcd.'\ '\'\\ \ \ m sr H^% ^\ ^ ZX) 03 ^ CD =o ^ ro 3> -< P^ rn I ,^\^ DEDICATED TO THE GAMEKEEPERS ON THE GROUSE MOORS OF GREAT BRITAIN PREFACE TO POPULAR EDITION The present volume is an attempt to give, in an abridged and popular form, the results of the recent inquiry into " Grouse Disease," which were published last year in the Report of the Grouse Disease Committee. The need for a second and shortened edition of the Report became evident soon after the first edition had been published, for the whole of this first edition was absorbed within a few weeks of its publication, and, although the price was considerable, there would have been little difficulty in finding purchasers for at least double the number of copies available. It is impossible to reproduce the second edition on the same scale as the original Report, for the greater number of the coloured plates, which formed part of the work, have now been removed from the lithographer's stones. It is also felt that those who ordered copies of the work, on the assumption that the original edition would be limited in number, are entitled to expect that this understanding would be respected, and that any subsequent publication of the results of the inquiry would not be a mere republication of the original Report. The Committee have, therefore, decided that a popular work in an abridged form should be issued. Such a volume cannot include all the elaborate coloured plates and scientific details which gave to the original edition much of its special value. The Committee have come the more willingly to this decision in view of the widely expressed desire that its conclusions should be made available to a larger class of reader than would readily purchase the more expensive and detailed work. Many game- ix X PREFACE keepers and their masters, while deeply interested in the objects of the inquiry, are naturally not familiar with pathological science, and cannot be expected to follow the technical details necessary to show how each conclusion is arrived at ; indeed, such technical details might in many cases fatigue the mind and might deprive the book of its interest to the general reader. It has, therefore, been decided to leave out certain of the purely scientific portions of the original Report, and only to refer to such pathological details as are necessary for the proper apprecia- tion of the conclusions to which they have led. It is without apology that the authors have omitted the long lists of speci- mens examined, the lists of subscribers and local correspondents to the Committee, the notes on experiments and the inventories of the contents of crops and gizzards. All these details have been recorded in the original Report for those who wish to refer to them, but they are out of place in the present volume. Many chapters in the original Report have been condensed or transposed so as to simplify and shorten the book. Chap, i., on " The Systematic Position of the Grouse," has been incor- porated with Chap. ii. into a chapter entitled " The Classification and Life History of the Grouse." Chap, iii., on the plumage of the Grouse, Chap, iv., on the food of the Grouse, and Chap, v., on the " Physiology and Anatomy of the Grouse," have been shortened. Chap, vi., on " The Weight of Grouse," has been omitted, but such portions of it as are necessary for the proper comprehension of the chapters on Life History and Grouse Disease respectively have been embodied in the chapters dealing with those subjects. In Part II., which deals with the diseases of Grouse, Chaps, vii. and viii., on " Causes of Mortality," have been combined into one chapter ; Chap, ix., on " Grouse Disease," has been shortened by the omission of much of the detail of past controversy on the subject. The first part of Chap. X., dealing with the threadworms of Grouse, has been PREFACE xi combined with Chap, xiv., on the Parasitic Protozoa, Chap. XV., on the Tapeworm, and Chap, xvi., on the Ectoparasites, into a chapter dealing briefly with all the Parasites and Protozoa of Grouse other than those which are directly responsible for " Grouse Disease." The subject of " Grouse Disease " proper is dealt with in the original Report under the headings of Chap, x., Strongylosis, and xi., Coccidiosis, and these two chapters are again published in an abbreviated form in the present volume. Chap, xii., on Pathology, and Chap, xiii., on the Blood of Grouse, are omitted, but reference to these subjects is made in some of the other chapters of the book. It will be seen that Part II. of the original Report has suffered very considerable reduction, but this is quite in accord- ance with the intention already expressed of making this book a practical guide to sportsmen and naturalists rather than a specialised study of the diseases of Grouse. With the same object, a special chapter has been added, in which an attempt is made to show how far the observations in the laboratory have been confirmed by observations on the moor, and though it is not claimed that this department of the investigations is complete, the chapter may indicate the lines on which future investigations may proceed. Part III., which deals chiefly with the management of Grouse moors, is of direct practical interest to moor-owners, and has been reprinted almost without alteration. As already stated, the lists and inventories which compose a great part of the Appendix to the original Report, are omitted, and the only other subjects dealt with in the Appendix are incorporated in Part II. of the present edition. Owing to the manner in which the work of separate writers has often been combined in the same chapter, it would be in- vidious to ascribe each chapter to the authorship of one or other of the Committee's Staff, but it may be of interest to give xii PREFACE the names of those who are principally responsible for the departments into which the subject has been subdivided. In Part I. the subject of Life History has been dealt with by Mr Leslie, the Secretary of the Committee, aided by Mr A. H. Evans, Mr E. A. Wilson, and the local correspondents of the Committee. The chapters on Plumage and Food are almost entirely the work of Mr E. A. Wilson, with notes on Insect Food by Mr P. H. Grimshaw, Grit by Dr H. Hammond Smith, and Mr R. H. Rastall, and Water by Mr Leslie. In Part II. Mr E. A. Wilson is chiefly responsible for the chapter on Causes of Mortality, and the chapter on " Grouse Disease " is written by him and Mr Leslie. The chapter on Ectoparasites and Endoparasites is written by Dr A. E. Shipley, who also, in conjunction with Dr R. T. Leiper, wrote the chapter on Strongylosis. The chapter on Coccidiosis is the work of Dr H. B. Fantham, and throughout this part frequent reference is made to the chapter on Pathology by Dr Louis Cobbett, and Dr G. S .Graham Smith, which appeared in the original Report. Part III., dealing with the question of Moor Management, Heather-burning, Keepers, Stock and Grouse Driving, are almost entirely the work of Lord Lovat, the Chairman of the Committee, assisted by the Secretary and other members of the Committee. The subject of the Heather Beetle is dealt with by Mr Grimshaw, and Grouse in Captivity by Dr Hammond Smith. The Editors have to acknowledge their indebtedness to the Zoological Society of London for their permission to include in this edition a selection of the plates representing the plumage of the Grouse which were prepared for the Committee by Mr E. A, Wilson and were first published in the Proceedings of the Society. They have also to thank Mr William Berry and Mr Edward M. Murray for their valuable assistance in preparing this volume for the press. A. S. LESLIE. July igiz. TABLE OF CONTENTS PAGE PREFACE TO POPULAR EDITION ix INTRODUCTION BY LORD LOVAT ..... XVU "^ PART I.— THE GROUSE IN HEALTH C a AFTER I, THE CLASSIFICATION AND LIFE HISTORY OF THE GROUSE 1 II. THE CHANGES OF PLUMAGE IN THE RED GROUSE IN HEALTH AND IN DISEASE .... 42 PART I. PLUMAGE CHANGES IN THE COCK. PART II. PLUMAGE CHANGES IN THE HEN. PART HI. ^LOCAL VARIATION IN THE PLUMAGE OF THE GROUSE. III. THE FOOD OF THE BED GROUSE .... 79 PART I. — OBSERVATIONS ON THE FOOD OF GROUSE, BASED ON AN EXAMINATION OF CROP CONTENTS. PART II. — THE INSECT FOOD OP GROUSE CHIOKSj BASED ON AN EXAMINATION OP CROPS AND GIZZARDS. PART III. — WATER. PART IV. — GRIT. PART II.— THE GROUSE IN DISEASE IV. CAUSES OF MORTALITY IN THE RED GROUSE . 113 A. THOSE REFERABLE TO ARTIFICIAL CONDITIONS. B. — THOSE REFERABLE TO NATURAL CAUSES. V. — "GROUSE disease" 151 HISTORY OF '' GROUSE DISEASE" WITH AN ACCOUNT OF THE WORK OP THE "grouse DISEASE" INQUIRY IN RESPECT OF PREVIOUS WORK DONE BY PROFESSOR KLEIN, DR COBBOLD, AND OTHERS. xiii xiv CONTENTS CirAPTER PAGB VI. — ANATOMY AND PHYSIOLOGY OF THE RED GROUSE 164 VII. THE ANIMALS WHICH LIVE ON OR WITHIN THE GROUSE 182 VIII. — " GROUSE DISEASE " — Continued — strongylosis . 206 PART I. — EFFECT OF STRONGYLOSIS ON THE GROUSE. PART II. LIFE HISTORY OF TRWHOSTRONaYLUS PERGRACILIS, IX. — " grouse DISEASE " — Continued — coccidiosis . 246 X. THE CONNEXION BETWEEN LOCAL CONDITIONS AND THE HEALTH OF GROUSE . . . 273 PART I. -t-ANALYSIS OF LOCAL CONDITIONS. PART II. — MAPS SHOWING INCIDENCE OF "GROUSE DISEASE." PART III.— MANAGEMENT OF GROUSE MOORS XI, MOOR MANAGEMENT 321 XII. — HEATHER-BURNING . . .... 343 XIII. THE HEATHER BEETLE 370 PART I. ON '^frosted'' HEATHER AND ITS CONNEXION WITH THE HEATHER BEETLE, LOCBM^A SUTURALIS. PART II. THE LIFE HISTORY OF THE HEATHER BEETLE, LOCHil^A SUIURALIS. XIV. KEEPERS AND KEEPERING, WITH SUB-DIVISIONS DEALING WITH POACHERS AND VERMIN . 387 XV, STOCK 415 XVI. — GROUSE IN CAPTIVITY 450 INDEX 459 LIST OF ILLUSTRATIONS PAIR OF BED GBOUSE IN SUMMER WITH YOtTNG CHICKS BLACK TYPE, IN FULL WINTEB BED TYPE, IN FULL WINTER PLATB I. n. MALE GBOUSE, PLUMAGE ni. MALE GROUSE, PLUMAGE IV. MALE GBOUSE, BED TYPE, IN FULL WINTEE PLUMAGE WITH A FEW BLACK CENTRED FEATHEBS OF THE PBEVIOUS AUTUMN PLUMAGE V. MALE GBOUSE CHANGING FBOM WINTEB TO AUTUMN PLUMAGE VI. FEET OF BED GBOUSE : (1) NEW WINTER FEATHERS AND NAILS ; (2) FULL WINTEB PLUMAGE ; (3), (4), (5) AND (6) SHOWING STAGES IN MOULTING OF NAILS Vn. FEMALE GBOUSE, BLACK TYPE, IN AUTUMN PLUMAGE Vm. FEMALE GROUSE, RED TYPE, CHANGING FROM WINTEB TO SUMMEB PLUMAGE . IX. FEMALE GBOUSE IN FULL SUMMEB PLUMAGE X. FEMALE GBOUSE, BED TYPE, FEATHEBS FBOM FLANKS XI. TYPES OP HEATHEB . . . . • xn. PLANTS EATEN BY THE GBOUSE (2 Figures) xin. PLANTS EATEN BY THE GBOUSE (2 Figures) xrv. PLANTS EATEN BY THE GBOUSE (2 Figures) XV. PLANTS EATEN BY THE GBOUSE (2 Figures) TEXT-FIG. 1. FBACTUBED HUMEBUS AND SCAPULA BE-UNITED „ 2. THE SAME BONES UNINJUBED „ 3. FBACTUBED AND BE-UNITED BBEAST- BONE OF A GREYHEN „ 4,5. FRACTURED AND RE - UNITED BREASTBONE — VIEWS OF BIGHT AND LEFT SIDE .... „ 6. FBACTUBED AND BE-UNITED BEEAST- BONE SHOWING METHOD OF UNION i» 7, 8. BROKEN AND BE-UNITED WING- BONES XV Frontispiece to face page 48 „ 49 „ 50 „ 51 ,, 53 „ 56 57 58 60 83 97 98 99 100 page 120 120 „ 121 „ 122 » 123 „ 128 XVI LIST OF ILLUSTRATIONS page 129 „ 130 to face page 166 186 TEXT-FIG. 9-11. BROKEN AND BE-XTNITED LEG- BONES . ... „ 12-15. BBOKEN AND RE-UNITED THIGH- BONES XVI. DIAGRAM OF ALIMENTARY TRACT SHOWING HABITATS OF INTESTINAL PARASITES . XVII. FIG. 1 aONIODES TETRAONIS (MALE) „ 2. „ „ (FEMALE) „ 4. „ „ (EGGS) „ 3. MMNOPON PALLESaJiNS (EGGS) XVIII. „ 1. NIRMUS OAMERATUS „ 2. „ (EGGS) XIX. ,, 1. ORNITEOMYIA LAGOPODIS . „ 2. OERATOPHYLLUS QALLINULM „ 3. SGATOPHAGA STERCORARIA TEXT-FIG. 16. DAVAINEA UROGALLl . „ 17. HYMENOLEPIS MICROPS „ 18. TRIGHOSTRONGYLUS PERGRAGILIS (male) ,, 19. TRIGHOSTRONGYLUS PERGRAGILIS (female) .... „ 20. MORITL^ IN EGG OF TRIGHO- STRONGYLUS PERGRAGILIS . „ 21, 22. DEVELOPING OVA OF T. PER- GRAGILIS .... ,, 23, 24, 25. FORMATION OF THE LARVA OF T. PERGRAGILIS „ 26, 27. EMBRYOS OF T. PERGRAGILIS HIGHLY MAGNIFIED 28-31. CHANGES IN T. PERGRAGILIS DURING ECDYSIS AND ENCYST- MENT „ 32, 33. LARVAL FORMS OF T. PER- GRAGILIS .... „ 34. ENCYSTED LARViE of T. PER- GRAGILIS .... ;, 35. OOCYSTS OF EIMERIA (GOGCIDIUM) AVIUM . . . . . ,, 36. DIAGRAM OF LIFE - CYCLE of EIMERIA (GOGGIDIUM) AVIUM XX. FIG. 1. HEATHER GROWING FROM THE ROOT . tO foce page 355 „ 2. HEATHER GROWING FROM SEED XXI. THE HEATHER BEETLE {LOGHM^A) SUTURALIS (4 Figures) „ 382 MAPS SHOWING INCIDENCE OF DISEASE, 1872-1909 poges 305-318 RAINFALL MAP OF SCOTLAND .... to foce page 320 187 188 page 93 198 200 »; 207 jj 207 ?> 222 *) 225 » 225 9> 227 >y 228 >* 230 s> 230 )> 247 ji 250 INTRODUCTION The importance of Grouse and Grouse Shooting not only as a form of sport and profit, but also as a means of support to a rural population has long been recognised. Grouse shooting is, of all forms of sport, the most profitable to the general population ; it causes little clashing of interests between the sportsman and the pastoral or agricultural tenant, whUe the policy to be adopted for the scientific management of moorland is equally beneficial to both. It produces a maxi- mum of profit to the wage earner with the minimum of waste, an otherwise unproductive subject is converted into a source of profit, and districts which but for the Grouse would be uninhabited, except by a solitary shepherd, are occupied by shooting tenants and the men employed by them, and the tenure of many small and otherwise uneconomic agricultural holdings is thereby rendered possible. In connection with all moorland sport one point stands out prominently — the land which is suitable for Grouse is not well adapted for anything else except sheep and cattle. But the pastoral value is in no way impaired by the presence of Grouse, for Grouse and sheep are found to flourish together on the same hillside; indeed the flockmaster is often under obligations to the sportsman for the labour which the latter expends upon the burning and draining of the moor. It has been stated that land which is at present given up to Grouse might profitably be reclaimed and utilised for agri- culture. Experiments have often been made. In the county xvii xviii INTRODUCTION of Sutherland alone over 100,000 acres were apportioned among an industrious class of agricultural tenants with a view to being brought under cultivation ; but the experiment was a failure, and the land gradually reverted to its former state. The best Grouse ground, that is ground that grows nothing but heather, is always of a poor peaty nature, and is incapable of growing crops to advantage. In this respect it differs from the green land where the soil is rich enough to grow grass and bracken ; this green land is of little value for Grouse, but might with advantage be planted with trees or even crops. It is probably true to say that in the selection of waste land for cultivation good Grouse ground is the last that would be chosen by practical agriculturalists. The value of Grouse Shootings to the proprietor is repre- sented by the shooting rents which they produce after deduc- tion of the expenses of management. Grouse rents have been steadily rising for many years past, and at present show no signs of falling off. This is scarcely to be wondered at when we take into account the limited number of Grouse moors available to meet the increasing demand. The popularity of this form of sport has indeed increased so much that it is now extremely difficult to secure a first-class Grouse moor on any terms, and even the smaller shootings seldom remain unlet. As might be expected, rents have tended to rise. Not many years ago £1 per brace was regarded as the normal rent to pay for a Grouse moor, now this rate is practically doubled in the more favoured districts. While it is clear from the foregoing remarks that the owner- ship of Grouse moors may be profitable to the proprietor, it is not the owners alone who benefit from this important source of revenue. It has been estimated that the approximate value of the Grouse moors in Scotland is about £1,000,000 a year in gross rent, and in England not less than £270,000. It has been further INTRODUCTION xix estimated that the foregoing gross rent may be apportioned roughly as follows : — Net profit to the proprietor about 34 per cent. Wages to the permanent staff about 35 per cent. Cost, of upkeep, interest on capital expenditure, value of gamekeepers' houses, wear and tear, rates and taxes, etc., about 31 per cent. The result in actual figures would therefore be — Profit £431,800. Wages 444,500. Cost 393,700. Apart from the direct profits derived from shooting rents. Grouse Shooting also produces a large amount of indirect profit to the community. This indirect profit consists mainly of wages for temporary assistants, such as drivers, ghillies, pony men, and dog men — ^traffic in household supplies, sporting requisites, hiring, carting, etc., and outlay on building, equip- ping, and maintaining shooting lodges. These indirect profits cannot be very exactly stated, but a fair estimate of their amount may be obtained when it is stated that it is the combined experience of shooting tenants that for every £l spent in rent from 15s. to £l is spent on other expenses connected with the undertaking. In spite of the favourable conditions referred to it seems unlikely that the rent per brace will continue to rise indefinitely, and moor owners have recognised that the best method of profiting by the present active demand is to develop the capacity of their moors so as to give as large and as steady a yield as possible. That this object can be achieved has been proved by the example of a few well-known moors, where the average yield has been increased by many hundreds per cent, as a result of judicious management. In the majority of cases, however, little progress has been made in this direction. The proprietor often has not the leisure to devote to moor management, some- XX INTRODUCTION times he has not the necessary knowledge, and very frequently his executive staff is insufficiently trained for the purpose. Another factor which has greatly hampered the owners' efforts to improve the yield of their moors is the constant re- currence of epidemics of mortality, more or less severe, among the Grouse stocks; this mortality always tends to break out wherever the stock has become unusually large, and its effect has been to produce a set-back in the bags just as they begin to show marked improvement. This mortality was found to be so prejudicial to the satisfactory development of Grouse moors that in 1904 a number df representative moor owners asked for an official inquiry into the causes of " Grouse Disease," and the methods to be adopted for its prevention. The outcome of their representations was the appointment of a Committee of the Board of Agriculture and Fisheries. This Committee carried on their investigations for a period of six years, and published the results in a Final Report, which appeared in the autumn of 1911. The present volume attempts to give the main findings of the Committee in an abbreviated form, and it is hoped that it may prove to be a useful handbook to those who have not an opportunity of referring to the original Report. LOVAT. THE GROUSE IN HEALTH AND IN DISEASE PART I.^THE GROUSE IN HEALTH CHAPTER I THE CLASSIFICATION AND LIFE HISTORY OF THE GROUSE The name Grouse, in the form " Grows," has been traced back The name by Salusbury Brereton to the reign of Henry VIII. (1531), ^°"^^' and in its present form to 1603. But, since it first occurs in an ordinance for the regulation of the Royal Household at Eltham in Kent, it ought in all probability to be applied to the Black Grouse which may then have inhabited that county, though no actual record has yet been discovered. Further particulars are given by Professor Newton in his " Dictionary of Birds." ^ The appellation has, however, by universal consent been long transferred to the Red Grouse, the Moorfowl of our forefathers, and when standing alone would never now be under- stood otherwise. This species is the most characteristic bird of the Scottish Distribu- moorlands, including the Hebrides and the Orkneys, and is plentiful thence to the northern counties of England ; in few ^ A. Newton, "Dictionary of Birda," p. 388. London; A. and 0. Black, 1893-1896. 1 A 2 THE GROUSE IN HEALTH AND IN DISEASE places is it more numerous than on the moors of South York- shire and Derbyshire in the vicinity of Sheffield ; while to the west it not only occurs in decreasing numbers to Shropshire, but is found in Wales as far south as Glamorganshire, and in Ireland in most suitable localities. Attempts have been made to acclimatise it to the north and south of its proper range ; but the few pairs turned down in Shetland between 1858 and 1883, with a greater number in 1901, have never thriven, while their descendants are apparently extinct, and the same may be said of those introduced into Surrey, Norfolk, and elsewhere, with three exceptions. The first instance is that noticed by Professor Newton in his " Dictionary of Birds," ^ where it is stated that Baron Dickson succeeded in acclimatising the species near Gottenburg in Sweden ; the second is that of its introduction in 1893-1894 to the Hohe Venn, a high tract of moorland on the borders of Belgium and Germany, south of Spa, where Red Grouse are still thriving ; and the third the successful experi- ment on Lord Iveagh's property at Icklingham in Suffolk in 1903, where the birds, despite the necessity of an artificial water supply on the dry, sandy heaths, had increased in 1909, and appeared likely in 1910 to form a permanent colony. In the Hohe Venn district after two failures fifty pairs or more were liberated in August 1894, and by 1901 had increased to about a thousand head in spite of regular shooting. Professor Somerville of Oxford, who has kindly furnished particulars, saw the birds there in September 1910. Classiflca- The Red Grouse of Britain belongs to Lagopus, the only genus of Grouse common to both hemispheres in which even the digits are feathered. This genus contains six well-defined species : the Spitsbergen Ptarmigan (L. hemileucurus) and the Rocky Mountain Ptarmigan (L. leucurus) — only found in the regions after which they are named — the Ptarmigan of Scotland and the mountains of the Palaearctic area {L. mutus), the " Iceland " Ptarmigan of that island, Greenland and the lower grounds of Northern Siberia and Arctic America (L. rupestris), the Willow 1 " Dictionary of Birds,'' p. 389. tlon. CLASSIFICATION AND LIFE HISTORY 3 Grouse of the north of Europe, Asia, and America (L. albus), and the British bird (L. scoticus) — with which alone we are concerned — indigenous in no other country. All the forms of the genus Lagopus are anatomically identi- cal, but the Red Grouse differs from the remaining members in that it does not turn white in winter. It has been thought to be merely the British representative of the Willow Grouse, though it differs from that species even in its summer plumage, and never possesses white wing - quills. It varies considerably in coloration, as will be seen from the following Plumage. quotation from " The Cambridge Natural History." " The male in both summer and winter is more or less chestnut-brown above, with black markings and a reddish head ; the lower parts are similar, but are usually spotted with white. In autumn the brown of the upper parts becomes buff and the lower surface is barred with buff and black. Mr Ogilvie- Grant recognises three types of plumage in the male, a red form with no white spots from Ireland and Western Scotland, a blackish variety comparatively rarely found, and another largely spotted with white below or even above. Intermediate specimens constitute the bulk of our birds. The female exhibits, moreover, a buff-spotted and a buff-barred form, but in summer she is typically black above with concentric buff markings, and buff below with black bars. Her autumn plumage, which continues throughout the winter, is black, spotted with buff and barred with rufous."^ Mr Ogil vie - Grant has recently published in the " Bulletin of the British Ornithologists' Club " ^ an elaborate account of the changes of plumage undergone by the Red Grouse, and of the points wherein he differs from Mr Millais and Mr Wilson ; but this is not the place to enter into controversial matters, and our readers must form their own opinions on the subject.^ Various reasons have been suggested for the absence of a white winter plumage in the British bird ; ' "Cambridge Natural History," vol. ir., Birds, p. 338. Cambridge, 1899. 2 "British Ornithologists' Club," vol. xxii. p. 122. London, 1910. ' Fide also chap. ii. pp. 42 et seq. 4 THE GROUSE IN HEALTH AND IN DISEASE for these reference may be made to the late Professor Newton's " Dictionary of Birds." ^ Pairing. No precise date can be given at which Grouse begin to pair, for this depends more upon the climatic conditions than upon anything else. In a mild winter Grouse will pair as early as December or January ; but if, after they are paired, the weather becomes rough and stormy, they will again congregate in packs, even after the usual date of nesting has arrived. The time at which they select their nesting ground (March and April) is also, to a limited extent, influenced by climatic conditions. On high moors, where the snow lies in late seasons till far into spring, it sometimes happens that during the whole winter, and even up to the month of April, there is hardly a bird upon the hill, the whole stock being congregated on the lower-lying moors where there is " black ground " on which food can be obtained. In such seasons it is interesting to observe the return of the stock to the higher parts as soon as the snow begins to melt. As a rule the birds do not pair upon the low ground, but congregate in packs upon the edge of the snow, waiting for an opportunity of returning to breed on their native hill. A good example of this was furnished in the spring of 1908 on a high-lying moor in Inverness-shire. During the preceding winter there had been a heavy fall of snow which lay for many months on the higher ranges, and drove the Grouse down in vast numbers to the lower levels. On the moor referred to there was not a Grouse to be seen until the snow began to melt about the end of April. But at the first sign of thaw the stock began to return, and as each patch of bare ground came into sight a pair of birds arrived as if guided by instinct and commenced to nest. That year the shooting season turned out to be a record one, for upwards of five thousand brace were killed upon an area of 20,000 acres, and many more might have been shot without unduly reducing the stock. While heavy snow during the winter may do little harm though it lies till far into the spring, a loss of stock may result 1 " Dictionary of Birds,'' p. 391. CLASSIFICATION AND LIFE HISTORY 5 where the fall occurs after the birds have returned to their nesting ground on the higher ranges. This occurred on a moor in Ross-shire in the year 1909, when a correspondent of the Conunittee reports as follows : "A heavy snowfall on April 24th put all the birds down to ' black ground.' They never went back to nest, and consequently the high ground, i.e., over 500 ft., was a failure, and the low ground better than usual." Again, a correspondent in West Perthshire writes : — " In spring, when the breeding season is approaching, a heavy snowstorm of some duration has on several occasions caused a most serious loss of stock, amounting to as much as half or more of the whole number of birds. After such a spring snowstorm and migration, large numbers of Grouse undoubtedly remain to breed on low and favourable moors within, say, ten or fifteen miles. These low moors are very heavily shot every year, but there is a constant migration of Grouse to them, both from overstocked moors, and from the high moors affected by snow." This is corroborated by a correspondent in the south of Scotland, who says : "I have an idea that if birds are forced to leave their usual ground (in spring), through deep untrodden snow, a good number may remain away and not return to their former ground." The subject of migration is more fully dealt with in another part of this chapter.^ During the mating season the pugnacity of the cock Grouse is well known, and in captivity the cocks have to be kept separate at this period, or disaster will certainly occur. Under natural conditions the fights seldom end fatally ; but it is certain that the presence of a quarrelsome cock-bird in search of a mate seriously interferes with the pairing of the other birds in the vicinity. Observation in the field goes to prove that old cocks are more pugnacious than young ones, and as they are less valuable for breeding purposes, the object of every moor- owner is to reduce the number of old cocks by every means in his power. ' See pp. 29-32. 6 THE GROUSE IN HEALTH AND IN DISEASE Nesting. The nest, a slight hollow scratched in the ground and lined with a scanty layer of grass, heather, etc., is usually placed on the sunny side of a tuft of heather, and preference as regards its site seems to be given to an area on which the heather is moderately well grown rather than where it is rank. Birds will always nest in a place where they can see all round, if possible, hence their avoidance of long heather.^ Dry ground is always preferred ; birds will not nest on boggy or damp ground, and are more likely to leave their nests on account of wet than for any other reason. On some moors where the heather has been very closely burnt or the stock is unusually large, the Grouse appear to be unable to find nesting ground exactly suited to their require- ments, and on these occasions they wUl boldly depart from their usual habits and will nest in short heather, flat dead bracken, or even on a bare unsheltered piece of burnt ground, leaving the nest as open as that of the Lapwing. It is important to note that in all cases open sites devoid of all covering are preferred to really long overgrown heather. The time of nesting varies according to the season and the latitude. As a rule most of the eggs are laid by the latter end of April and the beginning of May ; but a case has been reported of eggs being found as early as March 28th, and the Rev. W. B. Daniel records that " on the 5th of March, 1794, the Game- keeper of Mr Lister (now Lord Ribblesdale), of Gisburne Park, discovered on the Manor of Twitten, near Pendle Hill, a brood of Red Grous seemingly about ten days old, which could fly about as many yards at a time. This was an occurrence never known to have happened before so early in the year." ^ Macdonald ^ Macdonald in "Grouse Disease," makes the following statement : " The happiest condition in which a nest can be found is in growing heather of about a foot in length, and in the immediate proximity of short young heather." (Macdonald "Grouse Disease," p. 23. London : W. H. Allen & Co., Ltd., 1883.) And in another place he writes : " Grouse never nest amongst old, rough heather, always in a little tuft at the side or among the bent." {Ibid., p. 26.) Macpherson, in the Fur and Feather Series, states that "It is a fallacy to suppose that Grouse like to nest in very old heather." (Fnrand Feather Series, " The Grouse," p. 22. London: Longmans, Green & Co., 1894.) ^ Daniel, " Rural Sports," vol. iii., p. 108. London : Longmans, 1812. CLASSIFICATION AND LIFE HISTORY 7 states that the hen begins to lay at the end of March,^ while Macpherson, writing in the Fur and Feather series, says that " In the Island of Skye April 24th is a decidedly early date for a full clutch of Grouse eggs." ^ It is an interesting fact that, from the evidence obtained from many moors, of varying altitudes ranging from the south of Wales to the north of Sutherland, there is a difference of only two or three days in the dates when the earliest eggs are found ; March 30th in Yorkshire and Perthshire, and April 1st on high moors in Inverness and Sutherland are dates frequently recorded for the first nest. The date at which the first clutch is completed varies by a full fortnight on high and low ground and on north country and south country moors. In Yorkshire by the end of April many birds have begun to sit, while in central Scotland from April 25th to May 20th would probably cover the dates by which the full clutches are complete on most moors. The intervals between the laying of each egg vary greatly in captivity, probably also in nature, depending upon the weather ; for example, at the Committee's observation area in Surrey it was noted that one hen took twenty-nine days to lay ten eggs — an average of one egg every three days ; another laid only four eggs in twenty-six days, or an average of one egg every six and a half days. The clutch varies from seven to ten, and rarely reaches Eggs. twelve. Macdonald states that the hen lays eight to fourteen or sixteen eggs,* while Macpherson gives seven and eight as the most usual number of eggs, and states that " more than ten is quite exceptional." * Seebohm, who speaks with authority on all questions of British oology, states that the number of eggs laid would seem " to vary with the propitiousness or other- wise of the season. In very wet and cold springs the smallest clutches contain four or five, and the largest eight or nine ; whilst in very favourable seasons the small clutches are six ^ "Grouse Disease," p. 99. 2 Fur and Feather Series, " The Grouse," p. 21. ^ Macdonald, " Grouse Disease, " p. 99. * Fur and Feather Series, "The Grouse," p. 22. 8 THE GROUSE IN HEALTH AND IN DISEASE or seven, and the larger ones from ten to twelve, or even fifteen and seventeen ; but in the latter cases it is probable that the eggs may not all be the produce of one bird. In an average year most nests will contain seven or eight eggs. Birds which breed late on the high grounds do not seem to lay fewer eggs than those which breed early in the more sheltered situations." ^ A correspondent of the Committee in Forfarshire has reported a case of two Grouse hens sitting side by side — each on six eggs in a double nest ; and the Committee's field observer has seen two hens sitting on one nest with twelve eggs. For the following descriptive notes on the eggs of the Red Grouse in his "Birds of Europe," Dresser states that he is indebted to Seebohm : " The ground colour of the eggs of the Grouse is usually a pale olive, spotted and blotched all over with dark red-brown. The spots are frequently so confluent as almost entirely to conceal the ground colour. In fresh-laid eggs the brown is often very red, in some instances almost approaching crimson. It appears to darken as it thoroughly dries, and sometimes almost approaches black. When fresh laid the colour is not very fast, and before the eggs are hatched the beauty of the original colouring is generally very much lessened by large spots coming off altogether, no doubt from the friction of the feathers of the bird when sitting. If the weather is wet when the bird begins to sit this is much more the case. When the colour has once become thoroughly dry it will bear washing in water without injury." ^ In his most recent work Mr Dresser adds : " When blown and kept for some time, the ground colour fades to buffy white, and the spots and blotches darken in some cases to blackest brown. Those in (Mr Dresser's) collection measure from 1-60 by 1-14 to 1-82 by 1'32 inches. Mr Jourdain gives the average measure- 1 Seebohm, "British Birds," vol. ii., p. 430. London: B. H. Porter 1885. 2 Dresser, "Birds of Europe," vol. vii., p. 170. London : published by the author 1871-1881. ■' CLASSIFICATION AND LIFE HISTORY 9 ment of thirty-six eggs as 45-56 by 31-8 mm., and the average weight of eight eggs as 1*845 g."^ There is no truth in the beUef that disease will follow if the eggs are not well coloured. Very often the uncoloured part of the egg whitens at the same time as the coloured part fades or is washed off, thus making an egg of " bad colour." It is interesting to note that a bird of five years old lays fewer eggs and of a smaller size than a bird of one or two years old. The net yield of the nesting season greatly depends upon the weather in spring ; frost before sitting, snow after hatching, heavy rain following a drought when the birds have nested in low-lying ground liable to submersion, are some of the principal dangers to which early broods are exposed. The eggs also may be lost by a long spell of wet weather, even up to the point of hatching. This is probably not a matter of common occurrence, but in the spring of 1906 the Committee's field observer saw nest after nest deserted owing to rain. The nests on the low ground fared worst ; in some the eggs did not hatch at all, in others only one half, or even fewer, were productive. The parent birds seem to defy the elements at all times. Nesting in and during the period of incubation the hen will continue to sit upon her eggs apparently oblivious of the fact that a snow- storm is raging which has driven every other living creature off the moor. During such a storm hens are sometimes com- pletely covered with snow as they sit upon the nest, for in hard weather instinct teaches them not to desert the post of duty. Observation of the bird at these times is difficult, for even the most enthusiastic naturalist is not often tempted to explore the higher ranges of the ground in the face of a blinding blizzard. We must to some extent form our conclusions by observation of after-results, and certainly there is little doubt that the effect ' Dresser's " Eggs of the Birds of Europe," p. 623, PI. LXVII., Fig. 1. London: published for the author at the Office of the Royal Society for the Protection of Birds, 3 Hanover Square, 1906-1910. snow. 10 THE GROUSE IN HEALTH AND IN DISEASE Effects of wet. Effects of frost. of a heavy snowfall while the birds are sitting does not appear to produce the number of unhatched clutches of weather- bleached eggs which might be expected. Sometimes, no doubt, matters reach the limit of endurance when, urged by the pangs of hunger, the hen is forced to wander away in search of food and grit, and on her return finds all trace of her nest buried beneath a smooth, white drift. Even in this case all is not lost ; the snow fortunately does not lie long in the months of April and May, and in due time she recovers her nest and resumes her domestic duties. It is recorded that in 1908, on a Midlothian moor, a heavy snowfall during laying-time covered the nests to a depth of 9 inches for a period of ten days ; many eggs were lost, some even being laid on the top of the snow ; in many cases the hen bird returned to her nest after the snow had gone and laid more eggs beside those which had been covered — some of these birds hatched out every egg. Other cases have been reported where the eggs were covered with snow for so long that their colouring matter had dis- appeared, and yet they produced a healthy brood. From observations made upon Grouse in captivity it appears that during the period of incubation the hen will often leave her nest for several days at a time, for no apparent reason, and will return again and hatch out the whole clutch — this power of absenting herself without disaster to her eggs must under natural conditions stand her in good stead when the severity of the weather makes the task of incubation unendur- able ; but it is only in the earlier part of the sitting season that her absence is unattended with risk, for once circulation has commenced in the embryo chick the eggs must not be allowed to become cold. Only when the hen is forced to leave the nest on account of heavy rain is there a danger of her deserting the nest permanently— three days of incessant wet will suffice for this. Another danger to which the eggs of Grouse are liable is that of being destroyed by frost while the hen bird is oft the nest. This danger is greatest during the period before the CLASSIFICATION AND LIFE HISTORY 11 full clutch has been laid, for after incubation has commenced the hen will not readily leave her nest during frosty weather for any length of time. Before the hen commences to sit she will often cover up the eggs in the nest with twigs of heather, grass and bracken, and this must save many of them from the effects of frost. The Committee has had an exceptionally good opportunity of studying the effects of frost upon the eggs in the spring of 1908, when an extremely severe frost was reported from every district of England, Scotland and Wales. For three days in the third week of AprU the thermometer registered from 10 to 27 degrees Fahrenheit. The Committee requested its local correspondents to make careful observations on the resulting damage, and the replies received brought to light several interest- ing facts. In general it was stated that the effects of the frost had been disastrous ; but when the evidence came to be analysed the proof seemed strangely incomplete for very few reporters were able to state from personal observations that eggs laid before the frost had failed to hatch. On the other hand, several accurate observers reported that they had marked down eggs so frozen into the materials of the nest that it was not possible to lift them out or to separate them from each other, yet it was afterwards found that these eggs hatched out healthy chicks. On April 13th six Grouse eggs were found in a nest amongst heather when the temperature was 25 degrees of frost — and all six hatched out. On another occasion, when it happened that some Pheasant's eggs had been laid in a Grouse's nest, the Pheasant's eggs were the eggs which failed, while the Grouse's eggs were successfully hatched. Many observers went so far as to say that unless the frost was sufficiently severe to split the egg there was no danger of their fertility being affected, and of all the gamekeepers to whom the question was put very few could state that they had actually seen a Grouse's egg split by frost. Actual splitting of the eggs by frost does occur, but it is exceedingly rare when the nest is in its customary position 12 THE GROUSE IN HEALTH AND IN DISEASE in heather. When placed in the open probably the eggs are liable to suffer just as Plover's eggs did in 1908, and an extra hard frost will sometimes split them. Even very scanty heather-growth retains the warmer air, and so shelters the nest and eggs from frost and winds. Moreover, if sitting has not begun the eggs are generally more or less buried in the material of the nest, so that they are to a great extent protected. The effect of frost upon the eggs of Grouse has been fully discussed in the Committee's Report, and an analysis is given of the Reports of nearly 200 observers in different parts of the country.! Ti^g deductions to be drawn from this analysis, though negative, are nevertheless of considerable interest. They may be summarised as follows : — 1. Frost in the breeding season does not cause universal destruction to eggs. 2. In some cases it seems to do little or no harm, even though severe. 3. In other cases it seems to do more harm even though ■relatively less severe. 4. The effects of a hard frost in the breeding season are apt to be exaggerated especially if from any other less obvious cause there happens to be a shortage of young birds in the shooting season. How it happens that eggs in one district seem to be better able to withstand frost than those in other districts must remain a subject for conjecture. Acclimatisation appears a more probable solution than any other, for it is clearly brought out by the Reports that in the more rigorous climates of the north and east the eggs were less effected by frost than in the milder climate of the west. Possibly it may be that in the colder districts instinct teaches the parent birds to take greater pre- cautions, e.g., to nest under the shelter of long heather rather than in open situations. Many cases are recorded of Grouse protecting their eggs from frost by covering them with loose twigs of heather. ^ Vide "The Grouse in Health and in Disease," First Edition, vol. ii., pp. 132-136. CLASSIFICATION AND LIFE HISTORY 13 Enough has been said to emphasise the statement that the eggs of the Grouse are wonderfully tolerant of adverse weather conditions ; the fact is not sufficiently well recognised, and because occasional losses occur there is a tendency among gamekeepers to put down every failure of stock to some sharp frost or heavy snowfall in the months of April or May. They often do not inquire whether as a matter of fact any eggs were laid at the date when the frost occurred, they seldom support their statement by pointing out nests deserted by the hen after being buried in the snow, they keep the plausible explana- tion ready for use if required, and if the stock after all proves to be up to the average, they feel secretly rather surprised, but say nothing about the adverse conditions in the breeding season, for the excuse may be required the following spring. Thus much valuable evidence is lost owing to the very natural desire of the gamekeeper to prove himself the innocent victim of circumstances. Obviously, if the occasional snowstorms and moderate frosts of a normal April were really responsible for the damage so often attributed to them, it would follow that in a really inclement nesting season, such as occurred in 1908, the effects would have been disastrous throughout the length and breadth of the country. As a matter of fact, the bags in the autumn of that year, though unequal, were well up to, and in some places far above the average ; and even where a shortage of birds was reported the failure could often be traced to other causes than the unfavourable weather-conditions in the spring. While the evidence collected does not confirm the view that snow and frost in the nesting season are extensively destruc- tive to the eggs of Grouse, there is some reason to believe that unfavourable weather, occurring immediately before the date of laying, has an injurious effect upon the breeding powers of the parent birds. In the spring of 1908, for example, it was observed that on many moors birds which had paired, and were about to nest, became packed again on the arrival of frost and snow, and postponed their breeding operations until some 14 THE GROUSE IN HEALTH AND IN DISEASE Loss of scent while sitting. Hatching. time after the return of favourable conditions. The result was that they nested several weeks later than they would otherwise have done, and not only were their broods late, but the number of eggs laid was smaller than usual — some- times averaging only four and five in a nest. The resulting smallness of the coveys was often accounted for by the hypoth- esis that several eggs in each nest had been destroyed by the frost in April ; but there was little direct evidence of this, and it seems equally reasonable to suppose that the power of egg production had been impaired by the enforced postpone- ment of nesting. The data are insufficient to establish this theory, but the point is worthy of a passing mention. It is certain that some of the eggs are lost owing to their having been dropped on the snow and not in a nest at all. After a certain stage of development the egg is laid wherever the bird happens to be, and it is not uncommon to find eggs dropped in this accidental manner lying on the ground or on snow. During the nesting season the hen leaves her nest for a short time in the morning and evening to feed and drink, and her presence in any particular part of a moor may be known by the large " docker " droppings peculiar to a sitting bird. During the period of sitting the Grouse seems to be able to intermit its natural odour, and thus escape the notice of dogs and vermin. This point is noted by St John in " Wild Sports of the Highlands " when he states : " It is a curious fact, but one which I have often observed, that dogs frequently pass close to the nests of Grouse, Partridges and other game without scenting the hen bird as she sits on her eggs." ^ Probably the cause of the loss of scent is that when the bird is sitting still the air does not get amongst the feathers and so the scent is retained. The same remark probably accounts for the fact that at midday, when the birds are resting, they are very difficult to find with dogs. The young Grouse are hatched after an incubation of twenty- ' St John, " Wild Sports and Natural History of the Highlands," p. 29. London : John Murray, 1878. CLASSIFICATION AND LIFE HISTORY 15 three to twenty-four days, and leave the nest soon after they are freed from the shell. They are anxiously guarded by the parents, the hen being more attached to them than the cock, who, when they are disturbed, is the first to fly from danger, though it may be only for a short distance. The hen, on the other hand, will risk any danger rather than leave her brood — be it only a single chicken or two. Often, too, like the Partridge and many other birds, she will feign a broken wing and flutter over the heather, apparently in a terribly damaged condition, untU she has lured the intruder away from her brood. This fluttering action of the old bird should always be taken as a warning that the brood is young, that the squatting chicks are probably invisible, and that the danger of treading on them is great. It is most inadvisable when a cock or hen is flushed in the nesting season to walk about to see the size of the brood. It is at this stage that the weather conditions become im- portant, for the young chicks are liable to many dangers. It is true that they do not suffer from the cold, drizzly, sunless weather which destroys so many coveys of young Partridges, they are too hardy for that ; but heavy snow, hail, or rain often takes its toll and leaves little trace behind beyond the fact that the coveys are found to be reduced in numbers when they come to the gun. Probably the half-grown chick runs more risk from weather than when it is newly hatched, for its size prevents it from being completely covered by the hen when cold weather or heavy rain sets in. The period immediately following hatching, though so critical, is the period regarding which least is known. Few keepers like to disturb the ground at this time, and so the young bird's battle iov life is fought unobserved, and only the closest and most patient observation would reveal the true conditions under which the chick's existence is passed. The young Grouse, even although they may be squatting within a few feet of the observer, are very difficult to find ; they seem to have the power of making themselves invisible at will, as they cunningly crouch by the side of a tuft of grass 16 THE GROUSE IN HEALTH AND IN DISEASE or heather, which often matches in colour the yellow, brown, and chestnut mottled down that covers their little bodies for the first few weeks. When at last a chick is discovered and lifted up in the hand, its first " cheep " is the signal for the others to scuttle away out of their places of concealment, or, if they are upwards of a month old, to make their effort at escape by a short flight, after which they are apparently incap- able of a second attempt. It is astonishing how little accurate knowledge we have of the principal dangers to which the young Grouse is exposed. The practical gamekeeper admits that many dangers exist, and without weighing them too closely in the balance he does all he can to mitigate each of them. He knows, however, that in spite of his care there must be a certain percentage of losses from one cause or another, and it is with some. anxiety that he proceeds to the moor towards the end of July to inspect the condition of the stock. The result is sometimes unexpected, often he finds the birds have safely survived the perils of youth, and that the moor is well stocked with unbroken coveys ; at other times he is perplexed to discover that the well-filled nests and successful hatchings are represented by a few ragged broods of two or three birds, and a large number of barren pairs. He endeavours to account for the disappearance of the young birds, and in his search for a reason he eventually hits upon something which has some appearance of plausibility, and frequent repetition soon places theory in the realm of established fact. Migration is one of the commonest theories, and is supported by the fact that few, if any, dead bodies are found on the ground. The migration doctrine presents some difficulties, for the Grouse in its earlier stages is no^ by nature a wanderer, and a brood is usually found, at all events up to the end of July, not very far from where it was hatched out. Then, again, it is difficult to explain how on a large moor the young birds have departed before they are capable of sustained flight, especially if none of the neighbouring moors have received any noticeable addition CLASSIFICATION AND LIFE HISTORY 17 to their stock. Lastly, it is permissible to ask how is it that when the young birds emigrated to more congenial surround- ings they omitted to take their parents with them ? Each of these points presents a difficulty, and the combination of them renders the migration theory untenable as an explanation for the absence of birds at any time up to the beginning of August. Another favourite theory is that all the young birds have been drowned, and if it so happens that there has been a severe thunderstorm in June the theory becomes a certainty — ^though not a single drowned chick may have been found on the moor. There is no doubt that many young Grouse are destroyed by drowning, either as a result of being caught in a drain by a heavy shower, or by the flooding of low-lying ground. It is impossible to estimate the loss occasioned by drowning in sheep drains, owing to the extreme difficulty of detecting the small corpses in the swollen stream. One of the Committee's corre- spondents, a gamekeeper, who makes it a rule to inspect all the drains upon his ground several times during the nesting season, states that on one occasion only has he found a drowned chick in a drain. This evidence is, of course, only negative, and against it has to be reckoned the fact that many observers have spoken definitely as to the damage arising from this cause. On many moors the sheep drains have been scoured by floods into deep chasms, from which it would be difficult for the chick to emerge on the approach of danger, and any one who has seen a hill drain immediately after heavy rain, when it is run- ning bank high in a miniature torrent, can picture the risk which might attend any attempt on the part of the mother bird to lead her brood over the obstacle. Much may be done to minimise this risk by forming little backwaters in the drains, with shelving banks by which the yoimg Grouse may escape in time of danger. With regard to flooding, it is necessary to speak with more reserve. Flooding is a gradual process, and the instinct of self-preservation, which teaches the young Grouse to hide from his foes, will doubtless also teach him to retreat before the rising waters. In one case, however, flooding is B 18 THE GROUSE IN HEALTH AND IN DISEASE a real menace, for if the nesting season is a dry one Grouse have been known to nest in very unsuitable places, such as the beds of burns and dried-up pools and water-courses — often with disastrous results when the weather breaks. But, if there has been no rain, the drowning theory must be discarded, and its place is taken by the drought theory; in other words, the fine, dry, warm, sunny weather which is credited with producing a healthy stock in a good year is the cause of their wholesale destruction in a bad year. Nor do we know exactly what proportion of Grouse meet their fate from vermin ; that a certain number are killed by foxes, ravens, hoodie crows, stoats, weasels, and even gulls, may be admitted ; but when we come to apportion the blame we again find ourselves without sufficient evidence to amount to proof. The subject of vermin is dealt with more fully in a later chapter.^ Occasionally it is found that old birds as well as young have disappeared, and when this happens it is customary to ascribe the cause to " Grouse Disease " amongst the adult birds, for it is well known that if a parent bird dies from disease or any other cause there is little chance of her brood surviving. At a very early stage of the Inquiry it became evident that the loss of young stock on a large scale had never hitherto been properly accounted for, and required further investigation by the Committee. The Committee were able to offer a solution of this problem. During their Inquiry into the causes of mortality in Grouse they discovered a certain unicellular intestinal para- site, one of the Protozoa, a Coccidium, known as Eimeria avium, which in certain cases is most destructive to the young chick, but is rarely fatal to the adult bird ; this Coccidium is fully described in chapter ix.^ The discovery of the disease caused by this pathogenic organism and known as Coccidiosis justifies the view that when there has been extensive mortality amongst the young stock which cannot be accounted for in any other » Vide chap. xiv. pp. 403 et seq. 2 y^^g ^hap. ix. pp. 246 et seq. CLASSIFICATION AND LIFE HISTORY 19 way, it is almost certain that the chicks have met their fate by this infantile complaint. Coccidiosis as a disease of game birds and poultry is now being rapidly recognised in this country, and the disease is also being investigated in America. StUl there remains the difficulty that the dead bodies are not found in any numbers ; it must be remembered, however, that the infant Grouse is a small object, and any one who has searched in vain in the heather for a full-grown bird which has fallen to his gvm can realise the diffictilty of finding a tiny chick upon a moor where the whole stock does not average more than a bird to several acres. Coccidiosis chiefly attacks the birds when they are very small ; the chicks die in the heather, the little carcasses are rarely found, and in a short time they dis- appear altogether for, even if they have not been devoured by vermin or removed by heat, wet, flies, maggots, or burying beetles, the small bones do not make lasting skeletons, and would not be discovered even if the moors were searched. In spite of difficulties the field observer and other members of the Committee's scientific staff have by diligent search been able to find a certain number of small dead chicks on the moors; in almost every case the cause of death has been found to be Coccidiosis. Many other cases of Coccidiosis have been received for examination from various parts of Scotland and Yorkshire, or from the Committee's observation area in Surrey. Fortunately it is only in exceptional cases that we have to consider the question of a wholesale disappearance of the yoimg stock from pathogenic causes. Under normal circum- stances the Providence that watches over all young things brings to maturity a large percentage of the birds that are hatched ; but Providence may be assisted, and the methods by which it may be assisted are fully discussed in another part of this volume.^ Suffice it to say that in the earlier stages of the life of the Grouse the state of the moor is of great impor- ^ Vide chaps, xi,, xii., xiv., xv. 20 THE GROUSE IN HEALTH AND IN DISEASE tance to the welfare of the birds. If the heather has been well burnt in a systematic manner the chicks have access to shelter in time of danger, yet are not lost in a wilderness of rank growth should a shepherd's dog scatter the brood in all directions ; vermin is kept down, and, most important of all, there is easy access to a plentiful supply of suitable food in the strips or patches of heather which are available in various stages of growth. The place above all others where we may be sure of finding a brood of young chicks, if there are any on the ground, is amongst rushes and long grass in the more swampy parts of the moor ; this is specially noticeable in very dry seasons. Whether the chicks seek these damp spots for the sake of shelter from the heat or in quest of insect life is not known. Food of Flies, spiders, beetles, and greenish caterpillars about Grouse. |-inch long, as well as slugs and chrysalides, have all been found in the crops of chicks. Fresh Calluna heather shoots, moss capsiiles, and tender blaeberry leaves just opened, if they are to be had, are also generally present ; and as the young birds grow older heather becomes more and more their staple food.i In a chick of a few days old, where the food consisted of small caterpillars, there was no grit to be seen in the gizzard ; and, in another, the muscles of that organ, with its toughened lining, seemed sufficient to crush the soft blaeberry shoots. But it is the rule to find even in the youngest chick's gizzard a certain small quantity of fine quartz-grit and sand.^ When half-grown the crops of those examined contained a large percentage of heather, and the gizzards contained about half the amount of grit that is usually found in old birds, but in smaller fragments. Water, as supplied by streams and pools, does not appear to be necessary in the earlier stages where there is plenty of young heather ; insects, the succulent juices of the young heather shoots, and dew seem to provide all the moisture necessary. Broods are often hatched out far from any stream or pool, and they can generally be found within a few yards of the same 1 Vide chap. iii. pp. 101 et seq. a Hid,, p. 108. CLASSIFICATION AND LIFE HISTORY 21 spot till they are able to fly. On this point, as it affects the hand-rearing of Grouse, a well-known moor-owner writes : " I have never noticed that the young Grouse, when half- grown or older, require more water than what they pick up in the grass in wet weather, and what is sprinkled on the grass or heather at meal times, in dry weather. Old Grouse go to drink two or three times a day at most ; they seem to know how much is good for them ; whilst young Grouse, if allowed access to water, are apt, or almost certain, to drink too much, and scour. This, of course, refers to tame birds." Another of the Committee's correspondents (a gamekeeper on a large moor in central Perthshire) says : " Regarding water, I have known several broods fetched out 600 yards from the nearest water of any kind, in a dry season ; and they continued to thrive without water for at least three weeks after hatching." As the Grouse grows older, the parent birds relax their anxiety for the brood when disturbed, and, although they lie very close, the hen bird no longer flutters along the ground endeavouring to distract attention. Every keeper knows too well the danger that attends the needless disturbance of his beat at this time, especially in a high wind, which may carry the flushed birds hundreds of yards from their home. Instinct and the call of the parents may guide them back ; but it is better that they should be kept quiet. It has been noticed that when a young brood are once upon the wing, in anything like a strong breeze, they appear to be unable to alight with safety ; at the end of the flight they dash headlong into the heather, or on to the ground, and frequently come to an untimely end. With the arrival of August 12th the Grouse comes into the glare of publicity, and there is little relating to his life history between this date and the end of the shooting season that is not known to the average sportsman ; but even so there are variations in their habits in different localities which still remain a mystery, and it may be worth while to mention some of these. 22 THE GROUSE IN HEALTH AND IN DISEASE While in the majority of cases the birds appear to be wild in proportion to their growth, this does not seem to be the only- factor in the case, for in some districts on the west coast, notably in Skye, Grouse will sit close throughout the shooting season. It has been said that the reason for this is that in the districts in question birds of prey survive in larger numbers than else- where, and that the Grouse has not lost its instinct to sit close when in danger of attack by its natural enemies. This may be true, but is not altogether convincing, for it is well known that to sit close is no protection against the Eagle, though it may be against the Falcon, The Grouse instinctively knows this, and the appearance of an Eagle, or even a Heron, is the signal for all those on the alert to fly in terror to some distant place of safety. Feeding Grouse feed off and on throughout the day ; but it is only in the evening that the crop retains the food which is then required for use during the night. It is often stated that Grouse feed only in the evening, but the observations of the Committee make it quite clear that this is not the case though it is true that at midday the Grouse appear to feed less, and towards evening far more than at any other time. Midday is given up to rest, and, in summer, to shelter from the heat of the sun, and the evening is devoted to the complete filling of the crop with food for digestion during the night. Colquhoun in " The Moor and the Loch " refers to this habit as follows : "In sultry weather they lie quite still except at feeding time, and not having stirred perhaps for hours the dogs may come within a yard or two before winding them." ^ In the early part of the day and at dusk Grouse are found looking for grit on the rough moor roads and tracks, or along the burn-sides, where every fresh spate washes down a new supply. Gi'it' The attraction presented to the Grouse by a suitable supply 1 Colquhoun, "The Moor and the Loch," p. 184. Sixth Edition. Edinburgh, William Blackwood & Sons, 1884. CLASSIFICATION AND LIFE HISTORY 23 of grit is most marked. Good grit is to the Grouse what raisins are to Pheasants, and salt to Deer. They often fly long distances to obtain it, and in districts where it is scarce they will congre- gate in numbers along the railways and roads that traverse the moor, in order to avail themselves of the supply thus artifi- cially introduced. Towards midday Grouse are generally found on the " tops " and higher grounds, and especially amongst broken moss-hags ; or, if the weather be very hot, they may be flushed from the bum-sides and shaded places ; in very rough weather they do not scorn the shelter afforded by a ledge of rock or bank of peat, and may then be best approached down wind. The best shooting is often got late in the afternoon on the low ground, to which the Grouse have descended to feed before " juggii^g) " with crops crammed with heather shoots. When moving from one part of a moor to another Grouse usually fly low, and as their principal time for shifting their ground is in the early morning or at dusk they run a serious risk of death by collision with the wire sheep fences so common on many moors. This danger can be to a great extent averted by having all wire fences carefully " bushed " with bits of brushwood. Small branches of larch are best for this purpose, as they can be easily twisted between the wires, and do not readily blow out — a fair-sized branch every 5 yards is sufficient. Spruce branches are also used. Telegraph wires are not so common on a moor as fences, and not nearly so dangerous, while the cost of protecting the birds from them by game-guards makes it hardly worth while to consider them. The Grouse, like the Domestic Fowl, the Pheasant, and the Partridge, is a " dusting" bird, and wherever a peaty or sandy bank has a sunny exposure, a " scrape," with a feather or two half embedded in the soil, is to be seen. The fine particles of impalpable dust, by getting into the breathing apertures of the troublesome insects which are found on the birds, afford the latter temporary relief. Grouse also like to sun themselves 24 THE GROUSE IN HEALTH AND IN DISEASE on a warm bank or slab of rock — often resting with one wing extended. The practice of " becking " has been thus described in a note by Mr Alston in Dresser's " Birds of Europe " : ^ " Early on frosty mornings the cocks are fond of perching on a knowe or hillock and uttering their clear-ringing er-eck, kek-kek ! wuk, wuk, wuk. At such times they may often be seen to rise perpendicularly in the air to a height of several feet, and then drop again on the same spot." " Becking " is fully described by the Rev. H. A. Macpherson in the Fur and Feather Series, where it is pointed out that the practice is in the nature of an amorous demonstration by the cock Grouse with the object of attracting his mate,^ and it may be compared to the peculiar antics adopted by the Blackcock and Capercailzie from a similar motive. " Becking," however, is not confined to the breeding season, indeed it is more usual during the autumn and winter months than in the spring. Mr Macpherson describes in a most interesting chapter the manner in which Grouse may be shot by taking advantage of this peculiar habit. Grouse, when fully grown, do not pass the night huddled together like Partridges, but " jug " singly amongst the heather, taking care not to be far apart. From the traces left in time of snow it is found that they usually lie about a foot or two apart, so that a pack of a hundred may be contained within an area of a dozen square yards. In the words of a Highland gamekeeper : " Grouse glory in their ' hardiness,' " and it is almost incredible how little they are affected by wet, cold, and snow. It may indeed be said that so far as the adult Grouse is concerned it matters not what the weather is so long as his food supply is not affected. They will never desert high ground for low ground merely on account of a heavy fall of snow, provided that there is sufficient wind to keep the exposed ridges clear, and thus give access to the heather ; and even if the whole moor should be covered ^ " Birds of Europe," vol. vii. p. 168. 2 Fur and Feather Series, "The Grouse," pp. 65-72. CLASSIFICATION AND LIFE mSTORY 25 they will burrow in the soft snow to reach the heather under- neath. It is quite common to come upon birds in holes a foot or two under the loose snow. It is only when the snow has become covered with a hard, icy crust that the Grouse begin to feel the pinch of hunger. On these occasions they may be seen in large packs following in the track of a herd of deer or a flock of sheep in order to take advantage of the broken sur- face. They have even been known to eat the old unbumt stick heather which on all other occasions they reject as unfit for food ; but this is probably the last resource of the famine- stricken stock, and hardly justifies the practice of leaving a large amount of this unwholesome old heather as a food reserve in time of snow, for such a practice must greatly reduce the available supply of food at the critical period of early spring. A better practice is undoubtedly to burn all the more exposed ridges and knolls with careful discrimination, so that in which- ever direction the snow may drift there is a good chance that some good feeding heather will be left bare. It might be thought that where a heavy snowstorm occurs during the night there would be a risk of whole packs of Grouse being covered up and smothered by the drifts as the birds were jugging in a sheltered hollow. Sheep are often lost in large numbers by such misadventure, but Grouse never, for as they jug in the lee of a peat-hag or a moorland dyke they tread the snow under them as it falls, and are found next morn- ing safely collected on the surface, though their fresh droppings several feet below show the level at which they began their night's repose. It has been said that Grouse often avail themselves of the shelter of woods and plantations in time of snow ; but the evidence on the subject is contradictory. In some districts it has been found beneficial to plant trees as a shelter for Grouse ; in other districts, especially in the north of Scotland, they never use woods for shelter. It is generally believed that a hard winter with much snow is beneficial to the health of the stock in the following spring, 26 THE GROUSE IN HEALTH AND IN DISEASE and the reason commonly given is that the hard weather kills off the weaklings. There is no evidence to support this theory. Grouse are seldom found dead during the winter months, and when they are the cause can never be ascribed directly to the effects of weather. If the belief that snow is beneficial is well founded, some other reason must be sought ; perhaps the fact that the weather has caused the stock to shift, and so introduced new blood where required, may have something to do with the improvement : more likely, however, the solution is con- nected with the question of food supply. Ground which has been covered by snow for a period of several months provides better and more wholesome food than ground which has been heavily stocked, for when birds return in the spring they find the food supply still untouched by Grouse or Sheep, and the fact that it has been out of reach for so long has prevented it from being so heavily infected by the larvae of Trichostrongylus as the lower moors which were crowded with Grouse throughout the winter. The melting of the snow may also have the effect of washing the Strongyle larvte out of the heather. Packing. If the birds are well matured by August 12th they often begin to " pack " after the first few days' shooting, and will not then readily lie to dogs. Packing may at times take place so early as to make shooting over dogs an impossibility. On this account the poor results formerly obtained on most English moors led to the introduction of " driving." In Caithness and some other districts the Grouse, being more backward, do not pack except under exceptional conditions. This custom of packing is worthy of study, for it may be found to have a direct bearing upon the questions of disease, migration, interbreeding, and the preservation of the stock. In the first place, it may be stated that it is the young birds rather than the old birds that tend to form into packs in the earlier months of autumn, though the older birds will follow suit as the winter advances. Consequently, when packing first begins, it is the older birds that suffer the greatest loss in a CLASSIFICATION AND LIFE HISTORY 27 day's Grouse driving, for they come up to the line of butts in twos and threes, and are " mopped up " to a bird, whereas the larger packs of younger birds merely yield a percentage of their numbers to swell the bag. To this cause may perhaps be ascribed some of the beneficial results which attend the introduction of driving on many moors. Another important fact connected with packing is the tendency of the stock to separate into sexes — there are hen packs and cock packs, or at least each pack contains a large majority of one sex. It has been noted that certain hills in a range of moorland are frequented by hen packs, others by cock packs. The normal time for packing is in the autumn and winter months, and the more severe the weather the more marked is the tendency. Hens pack more readily than cocks ; the old cock does not appear to be of a sociable disposition, and often throughout the winter he will remain in solitary state, and only join the pack temporarily during a period of unusual storm. This tendency is often taken advantage of by those moor-owners who regard the old cocks as a menace to the health of their stock, and on many well-managed moors a rigorous crusade is carried on against the old single birds that frequent the bare tops, while their younger relatives occupy the lower ridges. During the winter months the advent of mild weather will often break up the packs for a while, and many cases have been reported of birds being scattered over the moor in pairs even in the months of November, December, and January ; but with the return of wintry conditions their gregarious habits assert themselves even up to the commencement of the nesting season. The reason why Grouse should pack in winter has often been discussed. The most favourite explanation is that they combine with a view to obtaining food in time of scarcity. Another theory is that, like many other birds and animals, the natural instinct of the Grouse is to congregate in flocks, and that this instinct is only departed from to meet the require- 28 THE GROUSE IN HEALTH AND IN DISEASE ments of the breeding season. It is probable that various motives induce the birds to congregate in packs. Some of these motives may be briefly mentioned, (a) To get on to the high bare tops out of the wet— it is observed that Grouse are always more packed after wet weather, (b) To go down to feed on the cornfields ; Grouse are seldom found feeding singly on the stocks ; this may be due to the natural timidity of the wild bird, which makes it fear to resort to the unwonted feeding- ground unless supported by numbers. The same rule applies with even greater force to the case of birds leaving their own ground and wandering far afield in search of food ; such migra- tions never take place except in large packs, (c) Owing probably to the same cause, Grouse invariably tend to pack after they have been much disturbed, especially by driving; on moors which for some reason have not been shot over for a season the birds do not pack until late in the year, (d) In dry weather small packs of two or three coveys are found at or near the springs even on August 12th. Undoubtedly, the most common cause of packing is scarcity of food. It has already been remarked that during the winter months the feeding area on every moor is restricted to those parts where the heather is of such a character as to resist the effects of frost and cold ; hence the birds tend to concentrate upon these food centres. The habit of packing is probably indirectly connected with the question of disease. If we admit that the congestion of a large number of birds upon small areas of moor is conducive to the deposit in dangerous numbers of the larval worms which cause disease on the favourite feeding-grounds of the birds, then it follows that the pack formation is in itself a danger to the health of the stock. This view is supported by the fact that where packing is the exception rather than the rule, as in the west coast of Scotland, disease is of rare occurrence. It is obviously impracticable to induce the Grouse to abandon this dangerous practice of congregating in packs ; but in another chapter suggestions are offered for minimising the risk of disease CLASSIFICATION AND LIFE HISTORY 29 by distributing and increasing the areas to which the packs may resort for food.^ In autumn, where a moor is near arable land, the birds will often come to feed on the stubbles and corn stooks ; they sometimes come in hundreds, and from long distances. This is not, however, the universal rule, for in some districts Grouse feed very little upon the corn, and in some seasons they appear to frequent the arable land more than in others. It has often been observed that by improving the heather on a moor Grouse may be induced to feed less upon the stooks. The change is often accompanied by an improvement in the health of the stock, and this has given rise to the view that corn is an unwhole- some diet for Grouse.^ In very severe weather the Grouse leave the high grounds Migration, entirely, and remove in packs many miles to the lower moors where they can find " black ground," or to a hill plantation where they can pick up a bare sustenance in the shape of various seeds. When they are very hard pressed, as in the winter of 1894, they even flock to the turnip fields, and instances of their alighting on thorn hedges to pick the haws are recorded in the Field of that year. In Argyllshire they have been known to feed on birch twigs during the winter — settling on the trees to reach the woody buds. The subject of the migration of Grouse is one which has engaged the attention of many naturalists ; but there has been a tendency among observers to note only the abnormal cases, and from them to deduce a general rule. One great obstacle in the way of accurate observation is the difficulty of identifying the original point of departure of the wandering packs. In spite of the confident statements of gamekeepers that they can tell by the size and plumage of a bird that he has come from a certain district many mUes away, it is more than probable that the newcomer has always had his habitation within a few miles of the neighbouring march, or even that he has never left his home, but has disguised himself by a sudden * Vide chap. xii. pp. 343 et seq. ^ Vide chap. iv. pp. 146 et seq. 30 THE GROUSE IN HEALTH AND IN DISEASE moult. In some districts imdoubtedly the birds shift annually in vast packs from the high ground to the lower moors, and return again in the spring to breed. On rare occasions migration takes place upon a much more serious scale, when the whole Grouse population of a district, driven by hunger, rises in huge packs and works its way south- ward in search of food ; this never happens unless a heavy undrifted snowfall has been followed by a hard frost, whereby a whole district is covered with an impenetrable sheet of frozen snow, thus cutting off all access to the heather. Such whole- sale migrations often result in a complete loss of the stock, for the birds appear to lose their bearings, and though they may sometimes find a haven on some distant moor, where weather conditions are more propitious, several cases have been recorded of the packs being seen on the low ground 20 or 30 miles from the nearest hill, or even flying out to sea, whence presumably they never return. In the case of normal annual migrations many opportunities have occurred for observing the power of flight of the Grouse. The following passage may be quoted from Macpherson in the Fur and Feather Series : ^ " When snow and sleet have driven them down from the hills they will then fly long distances. It is not at all unusual for Red Grouse to cross the Solway Firth at a point where the estuary measures two miles in breadth, and I have known them fly longer distances. They often cross the valley of the Tees, flying about a mile from one hillside to another." Millais also writes : " I have twice seen Grouse on the wing when they were crossing the ' Bring,' a wide channel which separates the islands of Hoy and Pomona, Orkneys. The fishermen told me this distance ... was quite four miles across, and the birds must have come at least another mile on the Pomona side from the point where they left the moor." ^ In Millais' " Game ' Fur and Feather Series, " The Grouse," p. 36. & Co.™!' " ^'"'' ^"^' ^""^ ^^°°^^^ Sketches," p. 53. London : Henry Sotheran CLASSIFICATION AND LIFE HISTORY 31 Birds " it is stated that Grouse have been observed flying from Thurso to Hoy, a distance of over 11 miles.^ The following instances are vouched for by the Committee's own corre- spondents. A gentleman in Banffshire, writing in January 1907, says : " Packs of Grouse are continually flying across the valley during stormy weather, some 5 or 6 miles between moors ; " while in Cumnock, in Ayrshire, there are " two ranges of hills divided by a valley about 2 miles wide, with a moss lying in between. In the pairing season Grouse often fly at a considerable height over the valley between the hills." Even during a Grouse drive a pack has been observed to leave the hill where it had been flushed, and not to rest until it had reached another moor 6 miles distant. Longer flights are more difficult to authenticate ; Harvie Brown states that : " in the severe winter of 1878-1879, a pack of Grouse was seen crossing the Moray Firth in December, making for the Banff coast, as we were informed at the time by Sheriff Mackenzie of Tain. Much snow was lying at the time in East Sutherland and Caithness " ; ^ and Macpherson {loc. cit.) says also that " The Rev. M. A. Mathew records that a solitary Red Grouse was shot by Mr C. Edwards on the Mendips near Wrington, Somerset, in September 1885, and this he suggests must have crossed over the Bristol Channel, migrating from Brecon- shire." ^ Other records in " Birds of Essex," are quoted in Macpherson.* We are indebted to the same writer for the following informa- tion upon the general habits of migration among Grouse. " Their principal time for shifting about is in the evening after feeding, and again after ' becking ' in the morning. But they are particularly restless on many moors about the end of September and in October, especially the female birds, and the ^ Millais, " Natural History of British Game Birds," p. 54. London : Longmans, Green & Co., 1909. ' Harvie Brown & Buckley's "Vertebrate Fauna of the Moray Basin," vol. ii. p. 162. Edinburgh : David Douglas, 1895. ^ Fur and Feather Series, "The Grouse," p. 37. ■* Ibid., p. 39. 32 THE GROUSE IN HEALTH AND IN DISEASE first strong gale brings many of them off the hilltops, looking for more sheltered and genial situations. " Birds of both sexes will fly a long distance to a patch of black heather during a prevalence of severe frost and heavy snow, but the hens shift about in packs more irregularly than their male companions, and they are less partial to the high grounds, but seek the lower portions of the moor, and such as are most screened from the east winds. Grouse netters say that in fine open weather the birds fly very long distances when shifting about the hills." ^ Observations upon the wandering habits of individual Grouse have also been made where some peculiarity in the bird has made identification possible. An Ayrshire gamekeeper has told the Committee's field observer of a pure white Grouse which was seen and freely shot at on Glencairn and Upper Cree. It then disappeared, and was seen and shot at many times on a shooting 12 miles away. It was eventually killed by a gamekeeper 9 mUes away from either of these moors, and now forms a stuffed specimen in a case in his cottage. All this happened in one season. The question of the annual movements and migrations of Grouse are important as a guide to the best methods to be adopted for the regulation of stock. The fact that Grouse annually shift from place to place over a wide area forces one to the conclusion that co-operation is necessary rather than individual effort. For the same reason it is doubtful whether the benefit of introducing fresh blood (either in the form of eggs or of living birds) is confined to the moor on which the fresh blood is introduced. This remark would not, of course, apply to an isolated moor, or one in which for any reason the shifting habits of the birds are not fully developed. Weight. The weight of Grouse is a subject on which little has been recorded, yet it is one of great interest to the naturalist, for many facts in the life history of the bird are associated with the normal change of weight from one season to another. ^ Fur and Feather Series, " The Grouse," p. 77. CLASSIFICATION AND LIFE HISTORY 33 From a practical point of view the weight of Grouse is a most useful indication of the health of a moor, this aspect of the subject is fully dealt with in a later chapter ,i and in the present chapter it is proposed to describe only the seasonal fluctuations in the weight of healthy adult birds. It is found that sex is a primary factor in determining the weight of an individual bird. An adult cock Grouse is as a rule heavier than an adult hen when both are well grown and in really good condition. This is true all the year round, except in spring, for at this time when the hen begins to sit she is heavier and in better condition than at any other time of the year, whUe the cock is not at his best. There is, therefore, at this season, a tendency for the average weight of both sexes to approximate, and even for the advantage to be on the side of the hen. The difference in the fluctuations of weight between the cock and the hen bird is shown in the Table given below. Seasonal Variation in Average Weight of Healthy Grouse. The immediate reason for this difference in spring is prob- ably the one which naturally suggests itself ; viz., that the exigencies of courtship have a precisely opposite effect upon the male and female. In December, the adult cock Grouse's weight averages 24-22 ounces compared to 21*07 ounces for the hen, while in 1 Chap. viii. p. 215. 34 THiE GROUSE IN HEALTH AND IN DISEASE January it is 23-58 ounces compared to the hen's 21-52 ounces. These may be considered normal averages, the difference at this time of year being dependent wholly upon a sexual difference of size and build, body and bone. In other words, when the birds are all living under healthy conditions, and when the sexual instincts are in abeyance, the hen being less in all her measurements than the cock has a weight corre- spondingly less by 2 or 3 ounces. It is, therefore, essential that average weights, to be of use, should include the sexes separately ; and also if the weights be taken in August, September, and October that every bird taken for an average be adult. As winter proceeds, we may assume that, unless the weather is unusually open, food becomes less abundant, or, at any rate, less easily obtained and less nutritious ; " the sap goes out of the heather," as it is generally expressed, and there is a large proportion of dry, dark, woody, weather-bitten shoots. Data are elsewhere given to prove that the quantity of such food, both by weight and bulk, found in the crops of full- fed birds in winter, is much in excess of what is usually found in the crops of similar birds in summer. In winter, the crops of Grouse often contain five times as much food-stuff as they ever contain in summer.^ And, although several factors are at work to produce this difference, one of the most important is the necessity of eating a greater bulk of winter heather in order to arrive at the same total of food value. It might be expected that the weight of Grouse would suffer from the shortage of nourishment contained in the winter food : but, as a matter of fact, the average weight of both sexes gradually increases during the winter months until March, the worst and most trying month of the whole year for Grouse. February, March, and April must be considered months of greater or less starvation every year, since the winter food has been picked over, not only by the Grouse themselves, but by cattle, sheep, deer, and hares, and often, too, the whole moor has long ^ Vide chap. iii. Table I. p. 80. CLASSIFICATION AND LIFE HISTORY 35 been buried deep in snow, or the heather has suffered badly from frost or from the dry parching effect of north-east winds. Although the hen appears able to remain in good condition, the cock always loses weight to some extent — often far too much — at this time and in consequence suffers from a diminished power of resistance to " Disease." When thus half- starved, and long before he has any chance of recuperation, the exhausting necessities of courtship force themselves upon him. In February and March he commences to live an exhilarated but exhausting and unsettled life. He becomes bold, noisy, aggressive, jealous, excitable, pugnacious and magnificent to see. He struts, becks, flies constantly about from one hillock to another, defies all comers, fights viciously, eats little, and constantly attends his mate. The result of the nervous and physical strain of the breeding season shows its effects upon the cock by a sudden and rapid drop in weight from over 24 oimces in mid-February to about 21 1 ounces in March. With the hen, however, it is very different, for at this time she leads an even quieter life than usual. She feeds constantly, takes no part in the warfare of her mate, and becomes to a greater or less extent " broody." When in this condition she does not readily take the wing, and puts on flesh and fat. By the time she begins to lay she has a large store of surplus fat deposited throughout the body and in masses under the skin ; and from this reserve she draws during the three weeks of incubation. For the twenty-three days during which she " sits " she leaves the nest only for a few minutes night and morning to eat and drink, and her tracks and " docker " droppings are to be found always at the springs or drinking- places which happen to be nearest to her nest. At the beginning of the nesting season the hen Grouse weighs as much as a heavy cock, sometimes even up to 27 ounces ; but this holds good for a short time only. It is just during these two months of the year, April and May, that she suffers most from " Grouse Disease " ; an inexplicable fact, did we not know that for various reasons, which are given elsewhere, March is 36 THE GROUSE IN HEALTH AND IN DISEASE to be considered the most dangerous month of the whole year for infection with Strongylosis. As the hen sits, her weight, even in health, rapidly diminishes. She is living largely upon her reserve material, and has, in addition to produce from eight to ten eggs. This must be a considerable drain upon her system, since each egg weighs about an ounce, and each ounce so lost to her is an ounce of her " flesh and blood," the whole amounting sometimes to nearly half her eventual total weight. By the end of June, thanks also to the trials of a family, she reaches an average weight of less than 20 ounces, and by the end of July sometimes falls to 19-5 ounces, whereas the cock, benefiting daily by the improv- ing food and weather, gradually rises from 19 or 20 ounces in March to an average of 24 ounces iii August.^ It will perhaps throw light on the cause of the marked changes which appear in the Table if an attempt is made to account for them month by month. The sudden drop in the weight of the cock in February and March, for example, must be due to courtship rather than to shortage of food, for though food is scarce at this time the shortage makes no difference worth noticing in the case of the hens. This argument is borne out by the almost equally sudden rise as soon as the mating is over. The post-nuptial moult in the male takes place in AprU and May. It is complete in June, therefore any loss of weight in the replacing of new feathers would make itself felt in the earlier of these three months. From April to August the food supply is improving daily, and the weight of the cock Grouse gradually increases. And it is by no means easy to see why there should be a sudden drop in September unless it is due to the complete (male) moult to the winter plumage. As there is no correspond- ing drop in the hen, and, as we know, no similar moult, we are probably right in thus attributing the September fall in the weight of the male to this autumn moult.^ In June the hen undergoes a complete post-nuptial moult, 1 Fide p. 33. 2 See chap. ii. pp. 42 et acq. CLASSIFICATION AND LIFE HISTORY 37 changing from the now faded breeding or nuptial dress, to the autumn or summer plumage, and this she cannot do without an appreciable drain upon her resources, which is clearly reflected in her weight. In changing the winter plumage for a nuptial breeding dress in AprD she differs radically from the cock, who retains his winter plumage until the breeding season is over. The two sexes moult at different seasons, and each twice within the year. The details of the changes have been dealt with in another chapter.^ It has been pointed out that the cock bird begins to grow new feather in April and in August, whereas the hen bird begins to grow new feather in February and July ; and each of these moults appears to have a definite effect upon the weight of the bird. There are, therefore, fluctuations in the weight of the healthy Grouse which are partly due to the moidt, and are therefore seasonal, while others are purely sexual ; it must be noted that the seasonal fluctuations differ as to date in each sex. Both seasonal and sexual changes occur in normal healthy birds. These fluctuations must be fully recognised before any useful deductions can be drawn regarding the changes of weight in birds that are or have been diseased. The following list includes most of the conditions which commonly affect the weight of Grouse : — I. In Health. (a) Sex, generally in favour of the male, but in April and May rather to the advantage of the female. (6) Late hatching, producing birds of both sexes unready for the winter ; birds which have missed the best growing months of summer, and which therefore remain permanently undersized and of a poor physique though not actually diseased, (c) Moult, in the male taking most effect in March and in September ; in the female in July and 1 Vide chap. ii. p. 42. 38 THE GROUSE IN HEALTH AND IN DISEASE November ; probably always leads to some loss of weight in either sex. (d) Courtship, in the male always apparently a cause of loss of weight : in the female, owing to increased rest, with some change in the general metabolism and extra opportunities for feeding prior to incubation, seems to lead normally to a very considerable increase of weight. (e) Egg laying and incubation, gradually l,ead to a loss of weight, which becomes more marked when the hen has had the care of a family of chicks. These cares, notwithstanding the abundance of summer food, often result in producing the lowest possible weights in hens, such loss of weight being in some cases due to an attempt to rear a second brood. During the hen's incubation the cock recovers his weight, because the food supply is rapidly improving, and because his energies are no longer exhausted by courtship. (/) A shortage of good food in a bad winter must often be responsible for a great reduction in weight. Similarly the abundance of food in summer, autumn, and early winter must serve to counter- act some of the other causes of loss of weight. It would be interesting, were it possible to collect sufficient figures, to compare local variation in the average weight of healthy males or females with local differences in the geo- graphical situation, climate, height above sea-level, or the character of the subsoil. Particular districts have been credited with the production of birds distinctly above the average in size and weight. Midlothian, Caithness, and the west coast of Scotland each claim to produce exceptionally heavy Grouse. To establish this a much more extensive series of weights should be taken than has hitherto been possible. So far as the Committee have been able to ascertain, it is difficult to say with certainty that any one district produces birds of a definitely CLASSIFICATION AND LIFE HISTORY 39 heaAder type than any other. The result of the evidence collected may be shown in the form of an abstract : — Table showing Average Weight in ounces of Addlt Grouse in different counties during the month of august. SCOTLAND. Cooks. Hena. County. Number Weighed. Average Weight. Heaviest Bird. Number Weighed. Average Weight. Heaviest Bird. Argyllshire main - land 76 24-3 27-5 58 21-3 23 Mull 1 25 25 Caithness . U 23-6 . .. ... Sutherland 174 23-9 ... 174 21 Ross-shire 15 25-0 14 21-4 Inverness . 98 24-35 ... ... ... Moray Banffshire 4 10 23-37 24-1 io 20-8 Aberdeen . 48 25-0 48 21-4 Kincardine 32 23-23 ... 25 19-9 Forfar 12 25-3 ... 12 21-3 Perthshire 73 23-5 28 46 20.2 24 Stirlingshire Fife. 33 43 23-8 23-27 ... 31 20-4 24 Dumbarton 12 23-0 • •• 12 21-0 Haddington Peebles . 14 1 23-78 30-0 Ayrshire . 10 24-0 • •. 10 20-0 Berwickshire 12 240 ... 12 21-3 Average for Scotland 680 24-0 ... 452 20-8 ... ENGLAN] D, WALl 58, IRE] LAND. Northumberland 12 25-25 12 21-0 Durham . 5 25-6 ... 4 20-0 Cumberland ... 28-6 ... Westmorland 10 22-97 Yorkshire 62 24-2 • .. 62 2r-'5 ... Derby Wales 15 20 24-5 23-7 27-0 15 20 21-3 21-25 24 Ireland . 1 25-5 ... ... AverageforBng Wales, and Ir land,l eland J 125 23-92 113 21-3 40 THE GROUSE IN HEALTH AND IN DISEASE From the foregoing figures it will be seen that there is remarkably little difference in the average weight of Grouse from widely different districts, the extent of the variation being only 2 1 ounces in the case of cocks and 1| ounces in the case of hens. In the specimens weighed the cocks from Scotland showed a slightly higher average weight than those from England, whereas the hens were distinctly lighter. This might have been due to accident, but it is more probable that the birds in England, being earlier, might have reached a more advanced stage in their seasonal variation than in Scotland, and we have seen that in August the cocks have a tendency to drop rapidly in weight, whereas the hens are attaining a comparatively high average which they steadily maintain for a month or more. Had the weights been taken in September the hens from Scotland would probably have shown as high an average as the hens from England ; while the cocks from both countries would have shown a universal drop. The foregoing comparisons seem to indicate that Grouse throughout the British Isles are of very uniform weight, and that any fluctuations that may be noted are probably merely temporary variations due to the abundance or shortage of the food supply in a particular district. The heaviest cock Grouse which came before the notice of the Committee was one of exactly 30 ounces from Peebles. Macdonald, in " Grouse Disease," ^ says : " The Grouse in Scotland is a larger and finer bird than that met with in England," a remark which the above figures do not altogether uphold. Macpherson, in Fur and Feather Series, says : " The cock birds not infrequently weigh 28 or 28| ounces in the north of England, when in first-rate condition in every respect. Any- thing over 30 ounces is noteworthy, but a weight of 32 ounces is not unprecedented." ^ In Yarrell's " British Birds," ^ Red Grouse are said to be ^ Macdonald, "Grouse Disease," p. 103. 2 Fur and Feather Series, " The Grouse," p. 64. 3 Yarrell, " British Birds," vol. iii. p. 77 (edited by Howard Saunders). Fourth Edition. London : John Van Voorst, 1882-1884. CLASSIFICATION AND LIFE HISTORY 41 at their best, both as regards weight and plumage, in November ; but this is only partly true. Their best months are February, August, and December ; and one may say they are at a fair level of condition in those months. Various opinions have been expressed as to the age which a ^^e of ^ r o Grouse Grouse can attain, and a few observations on the subject may be quoted. On a Yorkshire moor a cock Grouse, which was recognisable owing to its having a broken leg which stuck out prominently at right angles, was known to have lived for nine years in a wild state. An Ayrshire gamekeeper, one of the Committee's correspondents, can vouch for a Blackcock living twelve years, and is of opinion that Grouse live as long. Another correspondent, a Forfarshire gamekeeper, is sure that many of the old cocks on the tops are ten years old, and if appearances go for anything the black old cocks so often killed on the high tops of many moors must have reached this patriarchal age. In view of the many dangers to which they are exposed the wild Grouse seldom gets the chance of dying of old age, and the duration of its life depends more on the severity of the shooting and the numbers of vermin than upon the bird's own longevity. Observations on Grouse in captivity tend to support the view that they can live to a considerable age. Unfortunately, in every case reported to the Committee where a tame Grouse has reached the age of ten or twelve years the bird has died an accidental death. CHAPTER II THE CHANGES OF PLUMAGE IN THE RED GROUSE IN HEALTH AND IN DISEASE The subject of the plumage of the Grouse has already been briefly referred to, and the chief object of the following chapter is to describe in greater detail the somewhat complicated series of changes which occurs each year in the normal Grouse, and to show to what extent a departure from the usual rule may serve as an indication of the health of individual birds or of the stock as a whole. Part I. — Plumage Changes of the Cock Grouse When a large number of skins of the cock Grouse are arranged together, side by side, according to the month in which the birds were killed, it will be found that, even taking into account the differences of well-marked local variations in plumage, the series can readily be divided into two very dis- tinct sets. Seasonal There is first a very marked uniformity in the plumage of changes. ^j^^ ^^^^ l^jj.^g killed from the middle of November to the end of June ; and likewise amongst those killed from the end of June to the middle of November. These two periods, November to June and June to November, mark the two seasonal changes of plumage in the cock Grouse. The first is a plumage worn throughout the winter and during the courting and breeding season of the spring. The second is a plumage worn throughout the late summer and early autumn. It is necessary to lay stress upon this general broad division 42 THE CHANGES OF PLUMAGE IN RED GROUSE 43 of the cock Grouse's plumage, and if a large number of skins can be arranged as suggested the time at which the Grouse has definitely changed from the one plumage to the other cannot possibly be overlooked. The birds obtained at the end of May are definitely in the darker and redder winter plumage, and those procured at the end of June are definitely in the paler and more buff - coloured summer plumage; those killed at the beginning of October are still partly in the paler summer plumage, and by the end of November all are in the darker winter plumage. It must, however, be added, that there is hardly a month in the whole year, or a Grouse skin in a collection of many hundreds covering every month of the year, in which one plumage only can be found unmixed with the other. This fact accounts largely for the misunderstanding which at one time existed, but which has now, we hope, been satisfactorily settled, in respect of the vexed question of moult and plumage changes in the Red Grouse, and their proper interpretation. Without referring in detail to the points upon which differ- ences of opinion have before now arisen, it may be shown that much misunderstanding upon this difficult subject is based upon a different rendering of facts into words, facts which were recognised and perfectly well explained by Mr Ogilvie-Grant in 1893.^ Both he and Mr Millais have made the subject of plumage changes in the game-birds, and especially in the Grouse, a special study, and it must be admitted that there are very few points upon which they have touched which seem to require further explanation and still fewer points, if any, which can be brought to light for the first time in connec- tion with the plumage changes of the Red Grouse. A mono- graph on the Red Grouse would, however, be obviously incom- plete without an account of the plumage changes of the bird itself ; and it so happens that during the six years of the Grouse 1 (1) " AnnaU and Magazine of Natural History" (6), xii., July 1893, pp. 62-65 ; (2) "Catalogue of the Birds in the British Museum," vol. xxii., November 1893, pp. 36-38; (3) "Annals of Scottish Natural History," July 1894, pp. 129-140, PI. V. and VI. 44 THE GROUSE IN HEALTH AND IN DISEASE ' Disease Committee's existence the collection of some six hundred Red Grouse skins, representing every age, phase, and change of plumage in that bird, has given a unique opportunity for an independent revision of the work already done — an oppor- tunity such as has never occurred before in the study of any single species of British bird for observing the effect of disease upon moult and feather growth. And although the work as it stands has been so nearly completed by the labours of the two ornithologists already mentioned, there are still points of interest to which attention may be drawn, especially in connec- tion with the marked effect which parasitism and other wasting diseases have upon the moult and growth of feathers, and it is to this influence of disease that attention will be particularly drawn in the present chapter. It is important to note the extraordinary irregularities which so commonly occur in the plumage of the Red Grouse owing to disease, whereby the deferred moult becomes in some years almost the rule, and the rule of health becomes almost the exception. Diseased conditions often entirely mask the normal plumage changes, and it is far more important to realise this than to examine thousands of more or less healthy birds shot in the ordinary course of events in the shooting season. It is almost incredible that a moult should be deferred from one season to another, or even to a third, and that the right plumage should eventually be produced if the bird, by means of good food and good weather, is at last enabled to recover its health and grow any new feathers at all. It is interesting to know that bare featherless legs and feet, which have so long been considered a sure sign of disease in the Red Grouse, may, in certain months of the year, be a natural accompaniment of really good health, while thickly feathered legs in the same month are a sure sign of deferred moult and of sickness. It is only when the proper season for the moult of the leg and foot-feathering is completely understood that we can attach an unfavourable prognosis to heavy leg-feathering when the legs should have been featherless, and an equally THE CHANGES OF PLUMAGE IN RED GROUSE 45 favourable prognosis to bare legs when the legs should certainly have been bare. To return, however, to the two plumages of the healthy- cock Grouse. They are distinguished by Mr Ogilvie-Grant as the autumn plumage and the winter-summer plumage, and he says further that the cock " has no distinct summer plumage." ^ It is perfectly easy to see what is meant by this, and also by the statement which follows, that the cock " retains the winter plumage throughout the breeding season." Mr Millais also, in speaking of the cock Grouse, makes use of the expression autumn plumage which, he says, appears late in June ; and he adds that the autumn plumage, together with the " spring feathers " (or what Mr Ogilvie-Grant considers the first beginning of the autumn plumage on the Grouse's neck), remain till the main moult in August and September. Mr Millais makes the following statement, which appears to be based on a misinterpretation. He says : " as a matter of fact the male Grouse sheds in September and August a plumage which is a mixture of its winter, spring, and eclipse feathers." ^ These so-called " spring " and " eclipse " feathers are no doubt, as Mr OgUvie-Grant holds, the commencement of the plumage which is completed gradually during the summer months, and which he has described as the autumn plumage. It is naturally a little misleading to find the autumn plumage beginning to appear in early summer, but so long as the term is understood to mean the paler, more buff-coloured plumage with bolder bars of black, which begins to appear first on the neck of the cock at the end of May or early in June, and is eventually cast for the winter plumage in October, there need be no real misunderstanding. That feathers of the previous winter plumage should be mentioned in speaking of the moult of this autumn plumage ^ " Handbook to the Game Birds," p. 28. (Allen's Naturalists' Library). London W. H. Allen & Co., Ltd., 1895. " In lit., "British Birds," for April 1910, vol. iii. p. 382. London: "Witherlej &Co. 46 THE GROUSE IN HEALTH AND IN DISEASE is also quite intelligible, since the old winter plumage of the breast and abdomen is being quickly shed and replaced by a similar new winter plumage at the time when the autumn plumage on the rest of the body is being cast. There are in addition very frequently a few feathers of the copper-red plumage on the chin really belonging to and remaining over from the previous winter plumage. Instead of going into further details, however, with regard to the two moults and plumages of the cock Grouse, it will be simpler at this point to take its plumage changes in detail, successively month by month, explaining as nearly as possible what can be gathered from the examination of a series of skins, including a number of specimens in all stages of disease as well as in health. The specimens illustrate every month of the year and most of the local variations to be found in England, Scotland, and Ireland ; and there are a sufficient number of sick as well as healthy birds to show the very great influence that disease has in altering the individual capacity for feather growth. Unless this effect, which results as a rule from excessive para- sitism, is fully recognised, there will always be misunderstand- ings upon the moult of this bird, for almost every Grouse in the country is to some extent infested with parasitic worms, and there are years when irregularity of moult is the rule rather than the exception. Moreover, it so happens that in autumn, when birds are being shot in large numbers, the survivors of the two worst months of the year for " Grouse Disease " mortality, that is, the survivors of May and June, are all con- valescing ; but they are convalescing with their plumage changes all retarded and put completely out of order and routine. In this way it is possible in September to kill two birds on the same day, both of which have the chestnut-coloured feathers of the winter plumage on the chin and throat; but upon examination it may be seen that in one bird the edges of these feathers are frayed and worn and the colour faded, showing that they have survived from the previous winter plumage ; THE CHANGES OF PLUMAGE IN RED GROUSE 47 whereas in the other bird they are hardly free of the scaly sheaths in which they grew, and are really precocious feathers of the coming winter plumage. In each sex the general change from winter to summer may be described as a change from a more richly-pigmented, darker, black and chestnut, or rufous-chestnut plumage with rather fine transverse black markings, to a less richly-pigmented, paler, buff or rufous-buff or tawny-buff plumage with character- istically broad black bars and transverse markings.^ In each sex, moreover, the characteristic buff and black broad - banded summer plumage in its special appearance on the dorsal aspect is given by the growth of feathers with large black centres and a few buff or tawny -buff subterminal bars of considerable width, and a terminal border or spot of the palest buff, which is a very conspicuous feature on the back of most hens, and often little less conspicuous in the cock. In the cock, however, this plumage appears just two months later, and is less beautifully developed than in the hen.^ There is without doubt a general broad resemblance, firstly between the cock and the hen Grouse when the former is in its " winter plumage " and the latter in its " autumn plumage " ; and, secondly, between the cock and the hen Grouse when the former is in its " autumn plumage " and the latter in its " spring plumage." The perplexing fact is that these general resemblances are not synchronous in the two sexes, for there is an interval of two months between the moult of the cock and hen. Beginning now with the cock Red Grouse in January, and Cook looking at the breast first, the uniformity of the series is a very January. conspicuous feature. Every healthy bird is chestnut or rufous- chestnut and black, with fine, almost vermiculate black cross- lines over it. Even in the blackest birds the throat and fore-neck are always of a rich copper-red colour, with very little or no black edging at the borders of the feathers, which are usually barred ^ See Plates II. to v. and vii. to x, ^ See Plate i. (Frontispiece). 48 THE GROUSE IN HEALTH AND IN DISEASE with black only on the actual chin. Here there may be also more or less of white tippings, even to the formation of two white moustachios leading downwards from the gape, some- times an inch in length. This may be a feature either of the black type or of the red^ (Pis. ii. and iii.). In some very red and black Red Grouse the abdominal feathers are also freely and broadly tipped with white ; and this may sometimes be seen even on the feathers of the upper parts. The legs and feet in this month are thickly feathered, and are white, or white with brownish barring. The claws are usually very long and strong. Occasionally a pale bleached feather of the preceding " autumn plumage " is to be found on the flanks, middle of the breast, or neck, and may be recognised by its frayed edges ; and in a very backward bird, where there are many such worn and faded feathers on the chest and flanks, this is invariably the result of sickness. Turning now to the back we find a general uniformity of chestnut, bright or dark, or of blackish feathers, with fine black transverse markings ; but again in almost every bird there may be found a considerable number of the old black-centred " autunrn plumage " feathers remain- ing, with their frayed and faded edges of whitish-buff (PI. iv.). On the lower back and rump the more worn and faded feathers predominate. The primary and secondary quills are complete, but only a few months old, having been renewed between June and August ; and the same may be said of the tail feathers. The following points in the cock Grouse of January are characteristic : — (1) The rich copper-red, generally unbarred feathers of the throat and fore-neck. (2) The fine barring of the chestnut, dark rufous-chestnut, or blackish-brown of the back, with the scattered back-centred feathers of the last " autumn plumage." (3) The thick white feathering of the feet and legs, which ' The whole chapter deals with the Red Grouse [Lagopus scoticus Lath.). The terms "black Red Grouse" and "buff-spotted or white-spotted Red Grouse" must not be confused with similar terms for other species of Grouse. PL II. (P.Z.S. 1910. /'/. Z.VA'/A'.) A]Hlre ^ Slt^iKli, Ltd MALE GROUSE, BLACK TYPE, IN FULL NyiNTER-PLUMAGE. PL IIL (p.Z.S. 1910. PI. ZXA'X) Andre i: Sleig'i; Ltd. MALE GROUSE. RED TYPE, IN FULL WINTER-PLUMAGE. THE CHANGES OF PLUMAGE IN RED GROUSE 49 soon becomes blackened and worn by the " burrens " or charred stalks of old burned heather. (4) The perfect flight-feathers of the wings and tail. (5) The very large claws. In February the cock Grouse is still in the darker winter plum- February, age. Young feathers of this "winter plumage " may still occasion- ally be found on the hind-neck, nape, and head in backward birds. In March the cock Grouse normally shows no change ; but March, towards the end of the month in exceptional instances individual birds may be found with a few precocious feathers of the autumn plumage making their appearance on the back of the head and neck. These are very probably feathers irregularly developed to take the place of those which have been lost during encounters with other males. In April the cock Grouse still shows no change. In this April, month there are often greatly increased opportimities for the addition of skins to a collection, because it happens to be a month of very high mortality from " disease." The birds are found not only by the keepers who are out early in the month in search of fox-earths, and who are generally also burning heather about this time, but also later by the shepherds when ranging the moor in the lambing season. Thus a very large proportion of males are badly diseased, and comparatively few birds are in perfect health. It follows that in the series of skins of cock birds representing the month of April, the great majority are very backward. Healthy birds have still the old, rich, red, copper - coloured throat of the winter plumage and fresh - looking " autumn " feathers round the neck, upper back, and mantle, while the winter and old autumn plumage of the rump and back is bleached and faded. The backward birds are easily picked out, as they have not yet assumed their " winter " plumage, and are still mostly clad in old, worn autumn plumage of the previous year. If an April bird has newly and thickly feathered legs and feet, it means, almost certainly, that the " winter " plumage has been put on very late. The healthy Grouse should now be moulting the June 50 THE GROUSE IN HEALTH AND IN DISEASE feathers of the feet and legs, so that bareness or lack of feathers in April becomes a sign of health, and thickly feathered legs a sign of sickness ; this is the precise contrary of the proverbial saying that bare legs indicate disease ; though at other seasons the saying may be applicable. May. In May the preponderance of cock birds found dead, and therefore of skins of cock birds showing belated moult, is again a large one. The healthy cock is stUl in his much-worn winter plumage, but on the head and neck more feathers of the new autumn plumage have appeared (PI. v.). In June as a rule, the mortality amongst adult birds, due to Strongylosis, is coming to an end. Late in June the healthy cock Grouse can at last be said to have changed into his com- plete " autumn plumage." The winter plumage persists only on the abdomen and lower breast, on the actual chin which is blackish with a few white spots, and on the throat, where a few red feathers still remain. The moulting of the quills and tail feathers commences towards the end of the month. The rump and back are now completely covered with new black-centred feathers carrying broad-barred buff and black bands, and a few have a whitish terminal spot, similar to that found in the female. The head and neck, breast and throat, are now clothed in broad-barred buff and black feathers, quite distinct from the more chestnut and more finely black-marked plumage of the winter. It is impossible on seeing a series of the birds showing this distinctive change to avoid noticing how closely this autumn plumage of the cock approximates to the nesting plumage of the hen, but it has arrived in the cock just two months later than it is normally due in the hen — far too late to be a breeding plumage. It appears almost as though the pathological post- ponement of the moult, a postponement which is, after all, nothing but a sign and a symptom of disease, has gradually developed into a normal habit in the life of the bird, and one is led to think that this habitual disability in the cock Grouse, which results from Strongylosis during the nesting, courting, and breeding season (a disability which causes the death of PL IV. (P.Z S. 1910. P/. /A'XV//.) '~X,\ CU K*T>. AnUre oc Sleiyh, Ltd. MALE GROUSE, RED TYPE, IN FULL WINTER-PLUMAGE WITH A FEW BLACK-CENTERED FEATHERS OF THE PREVIOUS A TTTUMN-PLUMAGE. PL V. (p.z.s. 1910. ri. Lxxxn^^ Andre & Sleigh. Ltd. MALE GROUSE CHANGING FROM WINTER- TO AUTUMN-PLUMAGE. THE CHANGES OF PLUMAGE IN RED GROUSE 51 about eight cocks to every hen in April and in May), may have caused the alteration in the season of the moult, simply because the vis vitce of the cock bird, insufficient as we now know it to be at the close of winter for the ordinary calls of reproduction, would be still more disastrously insufficient if preceded by an early moult. At the present time the cock undoubtedly breeds in the old winter plumage, without any acquisition of a new breeding pliunage, and, as has recently been pointed out by Mr Ogilvie- Grant, what have been regarded by Mr Millais as new " spring feathers " on the neck are in fact the old autumn feathers, which on that part of the body do not become worn and faded. It is unlikely that any feather of the Grouse is altered in pattern, tone, or any other character, when once it has completed growth and has been cut oft from the circulation, for once the circulation has ceased beyond the entrance to the base of the shaft, and once the feather is cut off from the circulation in the deeper living layer of the skin, it is no more likely or able to change the pigment which is responsible for its pattern or its colour than would be the same feather had it been plucked out and kept entirely separate from the bird. If there are, as has been held, distinct pigments, such, for example, as buft, black, and orange-red, in the various colour tones of the Red Grouse, it becomes easier to see that the loss of the red pigment, which is utilised for the eggs, leaves the buff and the black in greater quantity for the nesting season plumage. In the winter all three would once more be available. The whole question of pigment production and pigment distribution, intimately connected as it is with the question of the excretion of waste products and the deposition of fat, both in health and in disease, has not reached a stage which admits of dogmatic statement upon the subject of pattern change in feathers without moult. That the cock bird should moult the feathers of the legs and feet between March 30th and June 17th is no longer difficult 52 THE GROUSE IN HEALTH AND IN DISEASE to understand when the prevalence of Strongylosis is fully grasped. No bird is safe from the nematode infestment, and we have now reason to believe that the majority of cock birds are so badly infested that they are forced to defer the moult which in the hen takes place before nesting begins. It is, therefore, obvious that between March and June there will be every stage of good or bad leg and foot-feathering from the newly acquired thick, white winter stocking of the sick cock, and the naked featherless clean moulted leg and foot of the really healthy male bird in June. In July, again, the healthy cock bird will be found beginning to produce white feather tips over the legs and feet. July. In July the general appearance of the healthy cock is much lighter in colour-tone, and much more broken and mottled in pattern-character than that of the same bird in the winter. The claws are in many cases now ready to be shed, and the primaries, secondaries, and tail feathers are in moult. Some six or eight new clean-grown primaries are often to be found in July, and the long taU coverts are broad-barred buff and black. August. jj^ Augtist the cock Grouse has, of course, the appearance of full summer or autumn plumage, but it requires very little examination to see that he has already begun to put on feathers of the winter plumage. He now rapidly sheds the old feathers of the last winter's plumage which remained throughout the summer upon his breast and abdomen, and replaces them with the exceedingly handsome narrow cross-barred red or brown or blackish feathers of the coming winter plumage. There is no second moult or replacement of these feathers of the breast and abdomen in the cock. Once in the year is enough for this special area, and the feathers that " carry through " are wholly of the winter plumage. They are often broadly tipped with white. The chin feathers which survived with those of the breast and abdomen are now also replaced by new ones. It is noticeable that in the Ptarmigan it is also the white feathering of the chin and of the breast and belly, as well as PL VI. (p.Z.S. 1910. /'/. AT///,) aA^^ 3c ^ 3b 3c ,."?■ ^,^"'^ Andre & Sleigh. Ltd FEET OF RED GROUSE : SHOWING STAGES IN MOULTING OF NAILS. THE CHANGES OF PLUMAGE IN RED GROUSE 53 of the wings and tail, which is changed once only in the year. In August, as has been said, the cock Red Grouse has begun to pUt on his winter plumage. The feathers of the breast and abdomen are full of sheaths and sheath-scurf, the growth of these feathers being very rapid and often scarcely noticeable. On the rump, back, and to a less extent on the shoulders, new rich red-brown feathers finely marked with black lines are showing here and there. Primaries, secondaries, tail feathers, and coverts are now replaced by new and blackish feathers with perfect and unbroken outlines. Even a few new rich copper-coloured feathers are appearing as isolated touches of bright colour amongst the faded broad-barred autumn feathers of the upper breast. The feet and legs are bare, save where new white feather tips are just appearing through the skin, and the claws of all the healthy birds are being shed (PI. vi., Figs. 1, 2, 3, 4). In September the chin and throat of the cock Grouse contain September. a mixture of many pale autumn feathers much worn and faded, and a few new copper-red ones. Most of the frayed " autumn plumage " feathers are now falling out. The breast and abdomen, wings and tails, are clothed with entirely new winter feathers, while the head and neck, back, shoulders, rump, and coverts of the tail are in a transition state, the " autumn " feathers frayed and bleached at the tips, contrasting with the new rich chestnut and darker brownish winter feathers with their fine black transverse markings. The feathers of the legs and feet of healthy birds are rapidly growing to form thick, white stockings for the winter. Bare legs in September are a sign of belated moult or, in other words, a sign of sickness. In October, for the first time since the preceding winter, October. the red and black varieties of Red Grouse become once more conspicuously distinct. This result is due to the new growth of fully pigmented feathers, either red or black, upon the under surface of the body. The upper neck is rapidly becoming copper-red. The chin and throat still show a proportion of 54 THE GROUSE IN HEALTH AND IN DISEASE the faded buff " autumn " feathers among the red, the former looking spotty and pale. On the back the new chestnut and black feathers are rapidly replacing the faded autumn feathers. The flight feathers which were moulted in June have now been replaced thus accounting for the fact that the adult birds as well as the young ones are stronger on the wing than at the beginning of the shooting season. Some perfectly healthy cocks still look as if in " autumn plumage," while others, on the con- trary, have nearly completed their winter dress. The legs and feet are thickly covered with white feathers, and the nails are uniformly small, as the old claws have all been shed. Their growth, however, is extremely rapid. November In November and December the cock Grouse drops most of December, t^e remaining " autumn plumage." By the end of the latter month his moult is complete, but on the neck and back a greater or lesser number of these autumn feathers are retained till the following summer. The most striking characteristics of the winter plumage are the rich copper-coloured neck and throat, and, in the darker varieties which are common in the Scottish Highlands, the contrasting blackness of the upper breast and abdomen often broadly flecked with pure white tips. Amongst the cocks there are several well-defined and easily recognised varieties, which seem to have a certain regularity of distribution geographically. These will be considered later. Part II.— Plumage Changes of the Hen Grouse. The two changes of plumage in the hen Grouse are completed, in the one case by the end of April or the beginning of May, and in the other case by July and August. The actual feather changes in both cock and hen are really very comparable in character, notwithstanding the difference of two months already referred to, they may be described and explained in very much the same terms. Mr Ogilvie-Grant was the first to draw attention to the THE CHANGES OF PLUMAGE IN RED GROUSE 55 exceptional want of agreement in the seasons chosen by the two sexes of the Red Grouse for their moult, and as in the cock's plumage he makes use of the terms " autumn " and " winter- summer " or " winter " plumages, which have therefore been used here, so in speaking of the hen's plumages it will be well to adhere similarly to the expressions used by him, and to call them " summer " and " autumn-winter " or " autumn " plumages. Exception may be taken, and indeed has been taken, to these names, as being inappropriate and inexact, but they are suffi- ciently exact for all practical purposes, and so long as moults and plumage changes are not completed in a week, but are spread over a period of several months, so long will there be some inexactitude in the terminology of these moults and plumages if they are named according to the months or seasons. It is immaterial so long as the term is sufficiently defined, for it is obviously impossible to use a term so exact as to require no definition. The hen Grouse moults twice in the year, and wears her " summer plumage " as the breeding dress from April to July, and her " autumn " or " autumn to winter " plumage from August to March. These changes may be expressed in terms of comparison with the cock, as a case of plumage change in which the hen has two annual moults, exactly as has the cock, but both moults occur two months earlier in the hen than in the cock. The hen's " summer " or breeding plumage is a very beauti- Breeding ful dress, variable to a considerable extent it is true, but yet ^ ^^^^ ■ having a general uniformity which becomes the more obvious as a greater series of skins in any particular phase of plum- age is examined. Opportunities for even seeing the hen Grouse, to say nothing of obtaining her skin, in the full breeding plumage are rare ; and thus it happens that, even in the large series of Grouse skins at South Kensington and at Cambridge, this phase is only poorly represented. 56 THE GROUSE IN HEALTH AND IN DISEASE The Committee has been to some extent more fortunate, and has obtained a great many skins of hens in the summer plumage, so that points of resemblance can be noted at sight, and individual variations perforce take their proper places. It has been a marked feature in the whole collection of six hundred skins that as the series grew, and the general uniformity became more marked, the individual variations which were so noticeable at first, became gradually relegated to their sub- ordinate position. Uniformity, albeit with endless minor variations, is the rule in the Grouse as it is in every other creature that leads an unprotected existence under natural conditions. How long it will continue in the protected, often over-protected. Grouse remains to be seen. It is possible that such variation as already occurs is to some extent a modern development ; but on this point there is at present insufficient evidence to amount to certainty. January. Beginning once more with January, it may be said that in this month some hens, when examined on the tmder side, are hardly distinguishable by their plumage from some cocks (PI. VII.), On the back it is different, and a healthy hen in January is unmistakable owing to the terminal spots of buff which appear almost invariably, though occasionally in limited numbers, on the feathers of the back. In some healthy hens the chin is sometimes still pale buff in colour, owing to the persistence of summer-plumage feathers of the preceding year. The throat and fore-neck, on the other hand, are copper-red, but rarely so imiformly red as in the cock (PI. II.). The copper - red feathers seem to begin on the fore - neck and proceed towards the chin, so that the chin often remains buff and black when the throat is already red. Except in very backward birds, which have been sick, the old and faded broad-barred feathers of the flanks are never found in January. The legs and feet are white and thickly feathered, and the claws are long and strong. February. In February the bird is still in the same plumage as in January. In a few forward birds the feathers of the summer PL VII. (P.Z.S. 1910. P/. ZAA'AT.) Amii-ui; Sleigh Lid. FEMALE GROUSE, BLACK TYPE, IN AUTUMN-PLUMAGE. PL VIII. (p.z.s. 1910. PI. z.rxvr//.) :? #p' #'^"' ^^: S '^•^' V,|> Andn; i^: Sleigh, Ltd. FEMALE GROUSE, RED TYPE, CHANGING FROM WINTER- TO SUMMER-PLUMAGE. THE CHANGES OF PLUMAGE IN RED GROUSE 57 dress begin to make their appearance on the back of the neck about the middle of the month. In March the change from autumn plumage to spring breed- March. ing plumage is, in healthy birds, now quite unmistakable, though many birds are very backward owing to disease. All doubt as to the sex of healthy birds, whether seen from above or below, is now removed. The broad-barred buff and black feathers of the flanks are now appearing, and are most con- spicuous and characteristic, while the whole of the lower breast and abdomen covered by the red brown or red-black finely barred feather of September growth are still in excellent con- dition and remain unchanged. The feathers of the chin, throat, neck, and upper breast are now mixed with broad-barred black and yellow feathers in forward birds ; whUe in backward birds the throat and fore-neck may still be clad in copper-red feathers. The legs and feet are already looking worn and less well feathered, but the claws are long. In April and in May, for the simple reason that many hen April and Grouse are infected with " Grouse Disease " in these months, ^^" the proportion of skins of backward hens is large. The birds thus picked up dead carry one immediately back again to winter, for although they ought by this time to be putting the finishing touches to their spring plumage, they are, in fact, but just succeeding in the belated effort to put on the autumn dress. They are thus a clear six months late, and afford the most misleading seasonal characters imaginable. Their legs and feet, instead of being worn and almost moulted clean, are at last,, after a winter spent with almost naked legs, well-clothed with thick white feathers. The appearance of the legs there- fore in the hens, as in the cocks, is totally misleading to the keeper or to the sportsman who considers bare unfeathered legs to be a sign of " Grouse Disease," for in April, May, and June none but healthy birds have naked legs and feet. The general character of advanced and healthy birds towards the end of April and in May is that of a complete spring plumage. The whole of the upper parts are broadly barred with buff 58 THE GROUSE IN HEALTH AND IN DISEASE June. Shedding of claws. and black, and marked with conspicuous terminal whitish buff spots or bars (PI. ix.). The under parts, again, are broadly- barred with buff and black, from the chin to the throat and neck, over the breast and down the flanks, while the central lower breast and abdomen are still in the autumn plumage of the previous September. White terminal spots may, of course, be present on the breast and abdomen. These are a local or an individual character which will be mentioned later in dealing with varieties of feather pattern and coloration. The flank feathers of the hen in the full spring plumage show much diversity of pattern. The legs and feet of the healthy hen Grouse in April and in May are very poorly feathered, but the claws are very long (PI. VI., Figs. 3, 5). In June the legs and feet are almost bare, and the claws begin to drop oft (PI. vi., Figs. 3, 4, 5). The precise date of this shedding of the claws is again really a part of the moult, and is, in consequence, equally dependent upon the health of the bird. Sick birds which haVe survived the spring mortality are always late in the shedding of their claws, and equally late in the changing of their feathers. The claws are shed, both in health and in disease, but once a year, and the casting is synchronous as a rule with the disappearance of the autumn dress. The figures (PI. vi.) by which this process is illustrated require but little explanation. The whole of the year's growth of homy black nail becomes loose on the soft and growing vascular matrix, and when quite ready to be cast can be easily pulled off like a little cap. The young nail beneath is at first soft, pink and vascular and very short, but soon hardens and deepens in colour, and in a month or two has grown to be a useful nail of horn. The transverse or circular groove which is left at the point of detachment of the old nail is quite a useful indication of age in cases where there is a doubt as to a bird being over twelve months old or of the year. The presence of the groove showing that the claws have once at least been shed is conclusive proof that the bird is more than twelve months old. PL IX. (p.z.s. 1910. /y. L.xxxvin) Andi-c & SleJyh, Ltd. FEMALE GROUSE IN FULL SUMMER-PLUMAGE. THE CHANGES OF PLUMAGE IN RED GROUSE 59 In June there is another characteristic appearance in the hens, namely the bare patch of abdominal skin which results from the shedding of the abdominal feathers, grown in the previous September. The loss of these feathers leaves a naked patch of skin on the abdomen of a hen that has been sitting, and this patch remains naked for the next few months. The general character of a June hen in health is that of the com- pleted summer-nesting plumage, broad-barred buff and black over all the upper and under parts, excepting the abdominal area, the lower breast, wings, and tail. But it looks already somewhat faded and worn ; and it is quite probable that in acquiring so perfect a plumage for sitting unnoticed on a nest built amongst the heather, the economic absence of the redder pigment in the feathers is in part a result of the acknowledged fact that for longer and more trying use, and for wear and tear in feathers, darker pigments are required, whereas for the short- lived and less exacting requirements of the summer plumage in the hen Grouse from April to June the buff and black feathers, with very much poorer wearing qualities, are found to be suffi- cient. The black pigmented parts of the feather stand wear and tear far better than the yellow parts. Certain pigments have a value, therefore, of a very practical nature apart al- together from the aesthetic point of view of attractiveness, or the rather hypothetical view of assimilation to surroundings for the purposes of safety or to assist in obtaining food. It very occasionally happens that the hen Grouse, instead of retaining the redder plumage of the previous autumn's growth on the abdomen luitil it drops off during incubation, grows an almost imiversal spring plumage of buff and black broad-barred feathers covering the lower breast and abdomen as well as the remainder of the body from head to tail. A skin showing this condition is preserved in the National Collection, and there is an almost equally perfect specimen in the Com- mittee's Collection. The more usual procedure is that the abdominal patch of autumnal plumage is lost during incubation, and is then quickly 60 THE GROUSE IN HEALTH AND IN DISEASE July. Distinction between young and old birds. replaced by a renewal of the autumnal feathers when the spring plumage is also being shed. There remains, however, in the majority of birds, a very quaint growth of belated spring plumage, consisting of buff and black-barred feathers in two lines down each side of the centre of the naked patch, as though, for some occult reason, the intention to grow " spring-plumage " feathers upon this area had never been altogether lost. This peculiar persistence of belated intention shows itself as a patch of yellow feathers made up of the two lines of feather growth in the midst of a much broader area of the autumn red pig- mented feather which one would expect to find all over the abdomen. In July the summer plumage of healthy hens is much worn out, frayed at the edges, and very definitely faded, and the feathers are already dropping out. On the chin, throat, and fore-neck, new red feathers of the autumn plumage, looking rich and dark, are already making their appearance. The back is as it was, but faded, and the flanks are still conspicuously broad-barred with buff and black ; but the abdominal bare patch is now growing new autumn plumage feathers with great rapidity from the centre outwards. The primaries and second- aries have now commenced to moult. There may be in July, in the hen, as many as six or eight old primaries in each wing with frayed tips, still to be renewed. Precocious young birds of the year can still at once be distinguished from hens in moult, because in the former the dark red-brown, black-lined autumn plumage is on the flanks, while the broad-barred buff and black, and rather worn- out chicken feathers are in the centre of the abdomen. In the adult the distribution is reversed. The broad-barred buff and black feathers of the spring plumage are on the flanks, and the redder fine-barred autumn plumage is appearing in the centre (compare PI. x., Figs, a, c, g, h, k, and n, with Fig. d.). The legs and feet in July are naked, and the claws are very small ; but the feathers are already showing through as small PL X. (P.Z.S. 1910. P/. A'C.) Andi'tr & Sleii^h, Ltd. FEMALE GROUSE, RED TYPE ; FEATHERS FROM FLANKS. THE CHANGES OF PLUMAGE IN RED GROUSE 61 white points, not to be confused with broken shafts, which occasionally result from wear and tear in woody heather. The plumage of the hen Grouse in August is well known. August. There are probably fewer diseased birds on the moor in August than there are in July. In July, however, they are never shot, and are therefore not observed, but in August they are care- fully picked out of every bag, and, owing to the general interest in the question of disease, are almost always noticed, and in some cases are publicly notified. Hence the idea that disease makes a new start in August and September. As a matter of fact, these wasted birds are almost certainly convalescent. They have been diseased, and they are still suffering from disease, but they have avoided actual death in the two highest mortality months, April and May. Once tided over these fatal months, the food and general conditions of life improve, the weight of the cock goes up, and the balance is again in favour of recovery for him ; and although with the hen the exigencies of incubation and the cares of the family continue to handicap her until June and even July, she then rapidly begins to put on weight, and in August and September is once more on the way towards complete recovery. Many sick-looking " piners " are shot upon the moors in August, but in September many that were not up to the average weight the month before are practi- cally normal, and would probably be indistinguishable from healthy birds, were it not that their serious indisposition of the preceding months has put them behind their fellows in the matter of feather change. In August, therefore, a collection of skins contains a large number of examples of hen birds showing deferred moult and belated growth of the autumn feathers. The normal healthy hen Grouse in August has already put off most of the broad- barred spring plumage feathers of her nesting dress, and is very much like the cock bird in appearance, with the same dark, red-brown vermiculate or fine-barred plumage underneath, white-flecked or not as the case may be, and with a mixture of old and new feathers above. The legs and feet of a forward 62 THE GROUSE IN HEALTH AND IN DISEASE hen are already showing quite a fair growth of white feathers, and the nails have all been shed. The claws are therefore short and rather soft, and the transverse sulcus or groove at the point of detachment is clearly marked. In the wings there may still be a number of primaries to be changed. In the convalescent " piner," on the other hand, the case is often very different. She has still a most deplorably bleached and weathered breeding plumage, with worn-out feathers, frayed or ragged, often with saw-toothed edges, showing the unequal effect of wear and tear on the pale buff pigmented and black pigmented parts. The bird in this belated plumage has quite naked legs and feet and long unshed nails, or may at the most be just showing the points of a new growth of feathers through the skin ; and in this state she is conspicuously shabby and ill to look upon in comparison with the splendid plumage recently acquired by her healthy sisters, and by the now almost universally healthy cocks. But the point above all others to be re- membered in this connection is that this hen is convalescent, and still has a couple of months of good food and good weather in which to complete her convalescence before the winter comes. If the spring outbreak of disease has been severe — ^that is, if the general conditions of the preceding winter and early spring months have been such as to conduce to a heavy and widespread infection of the Grouse with the larval Tricho- strongylus — ^then both cocks and hens will have been equally infested in April and May. .But the breeding season and the concomitant needs of the two sexes are, from April onwards, quite distinct from one another. The result of this is that there is often a large mortality of cocks in April and in May, and a much less marked mortality of hens, probably in the proportion of seven or eight cocks to one hen, but definitely occurring in the same two months. There is no great mortality from Strongylosis in any other months of the year, and after May the cocks are suddenly relieved and rapidly recover, so that by August there are almost no sick cocks ; the hens, on the other hand, have still two very THE CHANGES OF PLUMAGE IN RED GROUSE 63 trying months to face on account of the strain of laying, sitting, and rearing their broods, and although, thanks to the abundance of food, probably most of them succeed in struggling through, yet by August they have only just been freed of their more pressing cares, and a great number are still to be found in very poor condition. The recovery commenced, however, at the moment when the strain is removed, and it is this point which has so constantly been overlooked. Sick birds in August are convalescent, and however many there may be, they are not a sign of a new outbreak of disease, but a sign that the past spring infection was a heavy one, though less fatal than it might have been. At the end of their own specially critical periods, the cocks have at any rate June, July, August, and September in which to pull themselves together by means of good food assisted by good weather ; whereas the hens, at the end of their own specially critical period, have August and September. Hence the preponderance of sick-looking hens when the shooting begins, and the widespread, but erroneous, belief in a recrudescence of disease in autumn. To return to the further consideration of the hen's change September. of plumage in September, her finest feature is now undoubtedly the clean new growth of bright red, or dark red, or black and white-fiecked feathers of the breast and abdomen, with their narrow but even blacker markings. The whole of the old feathers of this tract have now been shed, but they grow again so quickly that no bare skin is visible save in the middle area of the abdomen quite low down, where, as has been already pointed out, the new growth is of belated feathers coloured as in the spring plumage, and therefore quite different from those around them. There is still, as a rule, no accession of new red feathers on the chin or throat of the healthy September hen, or at the most but a feather or two. But in the sick hen there is still often a sprinkling of the old red feathers of the preceding autvunn plumage. Very faded, amongst the faded buff and black feathers of the belated spring plumage. On the back of even 64 THE GROUSE IN HEALTH AND IN DISEASE forward hens there is still a mixture of old and new plumage, and the scapulars are often faded to something like black and white, and are badly frayed at the ends. The wings have now almost completed their moult, but there may still be a primary or two to change, even in very forward birds. The legs and feet are rapidly becoming feathered for the winter, though in backward birds which have been sick they are still quite bare, and now, of course, this feature may truly be taken to be a sign of sickness and disease, though in a convalescing bird. October. Jn October one may fmd a very backward bird with as many as three worn-out primaries in either wing to change ; but, as a rule, the wing is perfect, the primaries and secondaries and their coverts all completely new, and in the tail the rectrices are full grown. The legs and feet are now also fully feathered, though the thickness of the growth increases as the winter cold comes on. On the back the bird now looks fresh and richly coloured from head to tail, but a close search will always disclose a number of spring-plumage feathers which have still to be thrown off. Underneath, the rich red-copper colour is gradually replacing all the previous buff on the c,hin and throat. The change " hangs fire " a little on the neck and upper breast, but it is still progressing, whereas on the lower breast and belly the rich red or darker winter plumage with its beautiful fine black crosslines and pure white flecks is a very striking feature. There are, in the Committee's collection of skins, a number of examples showing the result of disease in deferring the moult ; many of these birds, even in October and November, have failed to get rid of the old, faded and completely worn-out spring plumage. The majority of these birds have been so diseased in spring that they have not bred at all. The ovaries have throughout the season shown no development, and there are no signs, even in the earlier months, of the shedding or develop- ment of ova or of any increase in size of the oviduct. They have been true barren hens. In some cases there appear, in October, feathers of three separate plumages. There are the faded spring-plumage feathers of the current year, but mixed THE CHANGES OF PLUMAGE IN RED GROUSE 65 up with them here and there are new feathers of the autumn plumage coming, and here and there exceedingly old worn feathers of the autumn plumage of the year before. One example, an October hen, shows exceedingly well how the bare, broody patch of the abdomen grows delayed broad-barred buff and black feathers instead of the fine-barred darker autumn- plumage feathers which surround the patch. These broad- barred feathers appear in two parallel rows, breaking through the skin of the broody patch on either side of the medial line ; this growth is also well shown in a specimen at the British Museum of Natural History. In November the chief alteration is the completion of the November. autximn moult and the assumption of the autumn plumage. The feathers of the upper parts have black middles, and are barred with rufous-chestnut and ornamented with the character- istic white or buff-coloured terminal spots. In December the hen is in full autumn-winter plumage. On December. the legs and feet she is well and thickly feathered ; and on the under side the chin and throat are dark red, as well as the fore- neck, marked with broader black bars than upon the lower breast and abdomen, where the marking is of the finer type, and the colour distinctly of the redder and darker autumn plumage. The following is a brief summary of the principal changes in the plumage of Grouse from January to December : — The Cock Grouse. January. — Full winter plumage. Breast, chestnut or reddish- brown and black with line black crosslines. Throat and fore- neck, rich copper-red with little black edging to the feathers, white moustachios, abdominal feathers often broadly marked with white. Legs and feet, thickly feathered and white with (sometimes) brownish barring, claws very long and strong {see PI. II. and in.). Bach, uniform bright or dark chestnut or blackish-brown with fine black transverse markings {see PI. iv.). Wings, flight feathers perfect, primary and secondary quills and retrices (tail feathers) complete. E 66 THE GROUSE IN HEALTH AND IN DISEASE A few paler feathers of the preceding autumn plumage still remain {see PI. iv.). When these autumn feathers are numerous they may be regarded as a result of delayed moult caused by sickness. February. — Full winter plumage. Autumn feathers are still present, but are only numerous in very backward birds. March. — Full winter plumage but very forward birds may show a few new autumn feathers ; some old autumn feathers are still present even in healthy birds. April. — Winter plumage is still the main character, but new autumn feathers are beginning to appear on the neck and mantle. The feathers of the feet and neck are beginning to moult, and bareness of legs in this month is a sign of health {see PI. v.). A few old autumn feathers still remain on the back and rump. Nearly all birds picked up dead in this month and in May are very backward, and have not yet assumed the full winter plumage which they should have completed in December. May. — A larger number of autumn feathers have appeared, but the winter plumage is still predominant, though by now it has become worn and dingy. June. — Late in this month the autumn plumage begins to prevail, though winter feathers still remain on the abdomen, lower breast, neck, and throat. In this month the quills and tail feathers commence to moult. The autumn plumage may be described as follows : Head and neck, breast and throat, broad-barred buff and black feathers not so rich or finely black-marked as the winter plumage. Back and rump black-centred feathers with broad-barred buff and black bands, a few with a whitish terminal spot. July. — ^Full autumn plumage, the general appearance is much lighter in colour tone than the winter plumage. The wing and tail feathers are in full moult, the claws also are ready to be shed ; but the feet and legs are beginning to grow new feathers. It should be noted that even in this month the winter plumage is still retained on the abdomen and lower breast ; there is no second moult or replacement of these feathers. THE CHANGES OF PLUMAGE IN RED GROUSE 67 August. — ^Autumn plumage is still predominant, but the new winter feathers are appearing, the old feathers of last winter's plumage remaining on the abdomen are rapidly shed and replaced. The new wing and tail feathers are completed. The claws are being shed, and the legs are still bare. September. — ^The autumn feathers, already very worn and frayed, rapidly fall out, the breast and abdomen, wings and tail have grown new winter feathers, but the upper parts are still in transition ; the legs are beginning to get their winter feathers. October and November. — Winter plumage almost complete in forward birds; flight feathers perfect; legs well feathered; claws small. December. — Full winter plumage with a few autumn feathers on neck and back, which are retained till following summer. The Hen Grouse. January. — Autumn or autumn-winter plumage. Throat and fore-neck copper-red, but not ♦so red as in the cock. Breast, bright or dark red or black, flecked with white {see PI, vii.). Back, chestnut, with black markings similar to the cock, but with terminal spots of buff. The old broad-barred feathers of the flanks are only found in backward birds. Legs and feet well feathered, claws long and strong. February. — Full autumn-winter plumage in forward birds, a few spring feathers are appearing on the back of the neck. March. — The spring or breeding plumage begins to appear in healthy birds. On the flanks broad-barred buff-and-black feathers are conspicuous, the lower breast and abdomen still retain the red-brown or red-black finely barred autumn-winter feathers; but on the chin, throat, neck, and upper breast forward birds show the broad-barred black-and-yellow feathers of the summer plumage. In backward birds these parts are still copper-red. The legs are less well feathered, but the claws are long {see PI. viii.) 68 THE GROUSE IN HEALTH AND IN DISEASE April. — Full spring plumage; on the back broad - barred buff-and-black with terminal whitish spots or bars, the breast flanks, chin, throat, and neck are similarly barred except on the lower breast and abdomen which still retain the autumn- winter plumage {see PI. ix.). The legs and feet are poorly feathered, but the claws are long. Sickly birds are still in full autumn plumage with well-feathered legs. May. — ^Full spring plumage. June. — Full spring plumage, but now beginning to look faded and worn ; the bare nesting patch is noticeable in hens that have been sitting. July. — The spring plumage is now much faded, and the feathers are dropping out. The rich dark autumn plumage is beginning to appear on the chin and throat. The back and flanks remain as before ; but the bare nesting patch is becoming covered with new feathers. The wing feathers are beginning to moult. The legs and feet are bare except in backward birds, and the claws are mostly shed. August. — The autumn feathdts, dark red-brown with fine transverse markings, has replaced the nesting plumage on the under parts, but on the back there is still a mixture of spring and autumn feathers. The legs and feet are beginning to show new feathers. The claws have been shed, and the new nails are small and soft. The wing feathers are still being moulted. Backward birds are very noticeable owing to their faded spring plumage, bare legs, and long claws. September. — ^The breast and abdomen is in complete autumn plumage, but on the chin, throat, and back there is still a mix- ture of old and new feathers. The wing feathers have almost completed their moult, and the legs are beginning to be well feathered. October. — The autumn moult is almost complete though a few old feathers remain on the back neck, and throat ; the wing and tail feathers are perfect and the feet well feathered. November. — ^Autumn moult completed. December. — Full autumn or autumn-winter plumage. THE CHANGES OF PLUMAGE IN RED GROUSE 69 Part III. — Local Variation in the Plumage op the Grouse. The following notes are the outcome of an attempt to find some broad differences between Grouse from the Highlands, the Lowlands, the east coast and the west coast of Scotland, and from English, Welsh, and Irish moors. It seemed possible that, with a large series of skins of a species peculiar to the British Isles, and at the same time so variable, one might discover points in the coloration of the plumage or in the size of the birds which could be attributed to the varying physical conditions under which they live. The artificial transportation of Grouse from one country to another, generally from the southern moors to the northern, often far removed from one another, with different food and climate, has no doubt to some extent confused the issue. But this is a diflBculty which will increase rather than decrease, and it is also possible that the purity of the British, breed (at present the only species of bird peculiar to our islands), may before long be impaired by the introduction of a foreign species, the Willow Grouse, on the mistaken supposition that the latter is freer from the parasite of " Grouse Disease." This foreign species has already been introduced here and there, and has to some extent interbred with our own Red Grouse. The Committee's collection contains five hundred and eighty skins of the Red Grouse, including five hundred and forty adult birds of both sexes and forty chicks and pullets. These, however, cannot be taken all together in one series. It is essential, for purposes of comparison, that the male birds in their two plumages should be taken separately in two lots, and the females in a similar manner. Therefore the skins have to be divided as follows : — Male birds in winter plumage Male birds in autumn plumage Female birds in autumn plumage Female birds in summer plumage Immature birds of the first six months No. of skins. 241 120 108 71 40 70 THE GROUSE IN HEALTH AND IN DISEASE The largest series of skins is therefore that of the male birds in winter plumage, and it so happens that this set, both as regards sex and plumage, is best adapted by its general uniformity to give some result when arranged map-wise over a large outline of Scotland and England. Having arranged the skins into lots which are sufficiently uniform to allow of comparison, and having arranged one of these lots, the cocks in their winter plumage, for instance, according to the localities from which they were obtained, it becomes possible to make the following deductions : — (1) That the general uniformity is very much more marked than might have been expected considering the character for variability which has always been attributed to the bird ; the variability is lost in the mass, though it is visible in individuals. (2) That, allowing for a good many exceptions, there is certainly a greater tendency to blackness in the birds of the northern Highlands than in those of the south. Or, one may say that in passing from the north of Scotland southward and westward, there is an increas- ing tendency to the bright red and dark red types of Grouse, which culminate in the very characteristically bright red bird of Wales and of the Midlands of England, in which the predominating colour of the feathers of the breast and under parts generally is red with fine broken black cross-lines, while these cross-lines are sometimes almost absent. (3) This gradual change from north to south of black, or red and black to dark red cocks, and farther south to bright red cocks is accompanied (speaking very broadly, for there are many exceptions) by a loss of the white terminal borders which characterise the feathers of the abdomen. There is no doubt that the blacker birds of the Highlands of the north of Scotland are more frequently white spotted beneath than the birds obtained farther south. Nevertheless, THE CHANGES OF PLUMAGE IN RED GROUSE 71 the white spotting is not entirely confined to the blacker or to the darker birds, though in the lowlands and in the north of England, especially in Yorkshire, it is only exceptionally met with. Mr Ogilvie-Grant, in his " Handbook to the Game Birds," 1896, says : " The ordinary varieties of the male may be divided into three distinct types of plumage : a red form, a black form, and a white-spotted form." ^ The red form, he says, " is mostly to be found on the low grounds of Ireland, the west coast of Scotland, and the Outer Hebrides" ;^ and this statement is borne out not only by the Committee's collection of Grouse skins, but by the interesting collection made by Mr T. E. Buckley now in the Cambridge Museum. Similar birds have been obtained in some numbers from Caithness, Sutherland, the Lewes, and Inverness-shire. From Stirling, Selkirk, Northumberland, and Wicklow only one or two have been examined, but in Wales the red type is almost always met with. Welsh birds are often most typically and uniformly very bright red. Dumfriesshire also undoubtedly produces a large proportion of the same red type. Bright red birds are not commonly characteristic of Ross- shire, Stirlingshire, or Northumberland notwithstanding the fact that an occasional example of this type may be found in these coimties. Dumbartonshire, however, and Argyllshire are said to produce more birds of a bright red type than other counties, and both these counties fall in with Sutherlandshire as forming part of the west coast of Scotland. Examples of the red type of the cock Grouse are given in Pis. III. and IV. The second or black form of cock Grouse is, according to Mr Ogilvie-Grant, rarely met with, most of the black birds being mixed with the red or white-spotted forms. In the Committee's collection there are a few very good examples of the really black type, and they come from the following areas : — Caithness, Sutherland, Perthshire, Dumbartonshire, and 1 " Handbook to the Game Birds," p. 27. ^ Hid., p. 28. 72 THE GROUSE IN HEALTH AND IN DISEASE Yorkshire. More or less typical examples have also been obtained from Ross-shire, Aberdeenshire, Morayshire, Kincardine, Stir- ling, Fife, and Lancashire. At Newcastleton the low-lying grassy moors are credited with the production of the black type of Grouse, while the other types are found on the higher heather ground. An example of the black type of cock Grouse is given in PI. II. " The third or white-spotted form has the feathers of the breast and belly, and sometimes those of the head and upper parts, tipped with white. The most typical examples of this variety are found, as a rule, on the high grounds of the north of Scotland." i This statement is again confirmed by the Committee's collection, although an occasional white-spotted bird makes its appearance farther to the south. The most marked examples of this white-spotted form Jjave come from Caithness, Suther- land, and Inverness, while Dumfries, Perthshire, and "York- shire have each provided one or two very fair examples. In Easter Ross birds are said to be most commonly dark red or black with white beneath. At Scrafton, Middleham, the majority have white beneath, and all are dark red or bright red ; still the predominance of white beneath is quite conspicuous in a geographical arrangement of a large number of skins, as a character of the north of Scotland, especially throughout the Highlands. Turning next to the female Red Grouse, no less than five distinct types are described by Mr Ogilvie-Grant : a red form, a black form, a white-spotted form, a buff-spotted form, and a buff-barred form. The difficulty in arranging hen Grouse into these classes is that a single bird may fall under three headings at once. A hen Grouse may be at once buft-spotted, white-spotted, and red or black, for the white spotting is an independent character and may occur on any type in the autumn plumage of the breast ^ " Handbook to the Game Birds," p. 28. THE CHANGES OF PLUMAGE IN RED GROUSE 73 and abdomen, and this may also be definitely of the red or the black type. In the Committee's collection, the first or red form is well represented from all parts of the country, and follows very much the same distribution as the red type of the cock Grouse. Red examples were procured from the following areas : — Sutherland (3), Argyll (9), Arran (1), Dumbarton (1), Cumberland (1), Westmorland (1), and Wales (3), all bright red birds ; Ross- shire, all dark red; Inverness-shire (3), very bright red and (3) very dark red birds ; Aberdeen (3), very dark red birds ; Stirling (4), red birds, with very fine black markings on the breast. Perthshire, Moray, Kincardine, Dumfriesshire, Kirk- cudbright, Northumberland, Durham, and Yorkshire were all represented by red hens, generally of the dark red type. An example of the red type of hen Grouse is given in PI. viii. The second or black form of hen is certainly, as Mr Ogilvie- Grant says, extremely uncommon, and only one or perhaps two of the Committee's birds should be included under this heading. Two others are, however, so dark as to come with difl&culty under the category of red birds. Caithness produced a really black hen bird, the sex of which could not possibly have been deterniined from its plumage. It appears to be an old hen, which has assumed male plumage. A specimen from Inverness is almost as dark a bird, and another is a Very dark reddish-black bird. A specimen from Dumbarton- shire is similarly a case in which there seems to be more black than dark red. An example of the black type of female Grouse is given in PL VII. The third or white-spotted form is less rare, and, according to Mr Ogilvie-Grant, occurs as often as in the male. In the Committee's collection it is well represented by birds from Sutherland, Ross-shire (a bird of the red tjrpe), and Inverness. It was less to be expected that examples should have been met with in Yorkshire, Lancashire, and Westmorland. Single examples were procured in Dumfries and Kincardine. There 74 THE GROUSE IN HEALTH AND IN DISEASE is a fine Irish example from co. Mayo in the British Museum (Natural History), No. 99 12.1.1. The fourth or buff-spotted form of hen Grouse, said to be " much the commonest and most usually met with, has the feathers of the upper parts spotted at the tip with whitish buff." 1 This type is generally distributed, and the Committee's collection includes examples from Caithness, Sutherland, Ross, Perthshire, Ayrshire, Kincardine, Dumfries, Northumberland, Yorkshire, Westmorland, and Lancashire. The fifth or huff-barred-form, according to Mr Ogilvie-Grant, " is met with in the south of Ireland, and resembles in winter (autumn plumage) the ordinary female in breeding plumage, having the upper parts coarsely barred with buff and black. Very little is known of this last variety, owing to the difficulty of obtaining birds except during the shooting season." ^ The repeated endeavours of the Committee to obtain specimens resulted in one hen only being obtained from Donegal. This bird was a very typical example of the buff-barred type, and it certainly differed from anything procured either in Scotland, England, or Wales. ' The nearest approach to it was to be found in four hens from Selkirkshire, and in hens from Inverness- shire, which might be more accurately described as buff-barred than as buff-spotted. Single examples from Lanark, Mid- lothian, Roxburgh, Haddington, and Northumberland might be classed in the buff-barred type, and the females from Yorkshire were all rather of the buff-barred type, but none of these birds had quite the same markings as the Irish example. Method of Two points in connection with the practical distinction of ingsex. old Grouse from young, and of cock Grouse from hens, are of perennial interest both to the gamekeeper and to the sportsman. No discussion is more apt to produce different opinions than that which arises upon the age or the sex of Grouse in certain stages of moulting. It must be admitted that there are in- dividual cases in which it is almost impossible to tell the sex ' " Handbook to the Game Birds," p. 28. 2 jhid. THE CHANGES OF PLUMAGE IN RED GROUSE 75 until the bird has been cut open and the internal anatomy exa- mined. In these doubtful cases the only way to settle the point is to cut the bird open down the middle of the abdomen, carefully turn over the whole of the intestines from the right to the left— that is, from the bird's left side to the bird's right side — without tearing the attachments, and then, having exposed to view the flattened reddish kidneys which lie closely packed into the inequalities of the backbone and pelvis, to see whether an ovary or a testis is revealed overlying the uppermost portion of them. It may be said that there is no other infallible means of arriving at the sex of a Grouse at certain times of the year, for it has so often happened that experienced and careful game- keepers, who have handled Grouse for a lifftime, have certi- fied a specimen as a cock, when the specimen has turned out to be a hen, and vice versd. The mistake is unavoidable and excusable, for in certain individual Grouse in the autumn- winter pliunage there is no reliable characteristic in the feather- ing or in the supraorbital comb, or in any external part of the bird, by which the sex can be distinguished. In most Red Grouse, however, the confusion of sex is not possible, for it is a matter of common knowledge that for a great part of the year the cock and the hen are so wholly unlike one another as to make it difficult for any one who did not know the birds to believe them to be of the same species. Even in the summer months, when the cock puts on a plumage closely simulating the breeding plumage of the hen, there is a difference in the general tone and colour. It is only in the autumn and winter that it is possible to mistake the sex of individual birds. Generally speaking, the feathers of the head and neck give the best indication as to sex in the autumn-winter plumage. In the male the red colouring is, as a rule, far more uniform than in the female. In the male also there is, as a rule, an absence of black markings on these red feathers, except on the upper part of the head, on the crown, and nape of the neck. The cheeks are generally a clean bronze or chestnut-red colour ; so are the feathers of the chin, throat, fore-neck, and upper 76 THE GROUSE IN HEALTH AND IN DISEASE breast, giving the bird a very rich uniform red colour all over the head and neck. In the hen, as a rule, the whole of the feathers of these parts are crossed by narrow black bars, giving her more of the mottled and broken colouring which the cock bird only begins to assume in the early summer when he puts on the first feathers of his autumn plumage. The feathers of the chin are a very useful indication of sex from August to November, practically throughout the shooting season, for the chestnut-red feathers which can be found on the chin of the cock Grouse in every month of the year will be sought for in vain in the hen at this time. Even in December and January they are so imperfectly red as compared with the same ^d feathers in the male that one may almost say that red feathers are to be found on the chin of the hen only from February to Jvlj, when they become conspicuous on account of the contrast in colour with the increasing yellow- ness of the breeding plumage. These red feathers persist from her previous autunm- winter plumage exactly as do the feathers of the lower breast and abdomen. This persistence of winter-plumage feathers on the chin, lower breast, and abdomen is common to both cock and hen ; but in the cock they remain, as a rule, until replaced by the following winter plumage, persisting throughout the autumn plumage change ; whereas in the hen they are persistent only to June or July, and are entirely replaced during the autumn change. Even when the autumn plumage is put on, the yellow feathers of the preceding breeding plumage are almost always to some extent persistent, and they are to be found in the chin of the hen bird even though the throat and neck may be un- usually red and therefore unusually like those of a cock bird. From January to May there is no possibility, as a rule, of confusing the sexes. In June and July confusion is unlikely, but in August and onwards to December the differentiation of the sexes by the plimiage is sometimes a difficult thing, and the best guide is the persistence of feathers of the preceding plumage such as occurs upon the chin in particular. We must recollect THE CHANGES OF PLUMAGE IN RED GROUSE 77 thiat the dominating plumage of the male is the winter plumage, while that of the female is the summer or breeding plumage. In the autumn, especially from September and October onwards, there is the additional difficulty of distinguishing old birds and young. To quote Mr OgUvie-Grant, " Young birds in July resemble Distinction the adult female in breeding plumage in their general colour, old and but the flank feathers of the adult plumage begin to appear ^?^^ about this time. By the month of November the young are generally not to be distinguished from the adults." There is one sign of age in the majority of birds in the shoot- Groove ing season, if it has not become obliterated — namely, the mark across the claws of recent shedding. Very often one may find the nails or claws still adhering to the toes, though ready to drop off, so that a gentle application of force removes them like small caps, leaving the new shorter claws beneath, each marked by a groove where the old claw was attached. This groove persists often for some little time, and is an infallible sign that the bird is over a year old at least. Young birds of the year do not shed their claws, and therefore never have this groove. There is another method of determining a bird's age which Wing is often used as a rough indication upon the moor, namely, to pull out the third primary feather of the wing at its distal end. If blood can be squeezed from the quill it is considered as a sign that the bird is of the year. If no blood can be squeezed, and the feather is old and dry, it is considered as a sign that the bird is more than a year old. This sign of blood in the quill of the third primary is not, however, an infallible sign of youth, for it is evident that as soon as the feather finishes its growth the quUl becomes as hard and dry and bloodless as all the others. The only indication will then be a slight difference in the shape and contour of the two last feathers as indicated above. Moreover, in September it is easy to find birds obviously adult with claws attached but on the point of being shed, and 78 THE GROUSE IN HEALTH AND IN DISEASE having all the primaries moulted except the two most distal ones. The third then will be found to be a short feather actively growing, and if it is pulled out the growing root will be full of blood. Therefore not every bird that gives this sign is necessarily a bird of the year. Lower bill. Another sign often used to test the age of a bird is the strength of the lower mandible. The weight of the bird is allowed to hang without support by holding the tip of the lower bill only. The bone of an old bird's jaw easily stands this test, but the soft jaw of a young bird of three or four months cannot carry its weight, and the jaw either bends or breaks. Skull, Yet another test often used is that of trying to crush in the skull with the finger and thumb ; in the young bird the soft skull gives way readily, in the old bird it requires very con- siderable force. In dissection, the age of an old bird is apparent, perhaps as plainly upon the table as elsewhere. The fibrous tissues all toughen with age and use, and the bones become harder. The grits of the gizzard in an old bird seem to be larger and more worn into roimded pebble shapes — the reason for this has been discussed elsewhere.^ The question, therefore, of deciding whether a bird is less than a year or more than a year old, is possible, but it seems almost impossible to judge more exactly of the age of an older bird by any sign to be discovered either externally or internally. 1 Vide chap. iii. pp. 107 e< seq. CHAPTER III THE FOOD OF THE RED GROUSE Part I. — Observations on the Food of Grouse, based on an Examination of Crop Contents. During the period of the Inquiry the contents of three hundred and ninty-nine specimens of loaded crops have been examined by the Committee with the express view of ascertaining the various foods eaten by Grouse ; the percentage of compositions have been tabulated, as well as the total weight of food in the crops at the various hours of the day, and by this means the Committee have come to several unexpected conclusions. In addition to those tabulated some eleven hundred other crops were examined, these were obtained chiefly from diseased birds in April and May, and from shot birds in August and September. The results correspond closely to those obtained from the tabulated specimens. The three hundred and ninety-nine specimens of tabulated crop contents are weU distributed as to locality and as to date. It is natural that by far the greater number should have been supplied during August and September ; but the other months are fully represented, and no fewer than thirty-three counties have contributed specimens. Table I. (p. 80) is drawn up to show the average weight of Time of the crop contents of birds killed at different hours of the day, from 6 A.M. to 6 p.m. In the last right-hand column of Table I. will be found a general average for the twelve months, and it will be seen from the figures given that Grouse feed from morning until night, 79 80 THE GROUSE IN HEALTH AND IN DISEASE TABLE I. — "Weight in Grains of Crop Contents, in which the Hour OP Collection was given, in Summer and Winter respectively. Hour of Collec- tion. Weight of Crop Contents of each Bird in Grains. (April to November. ) Weight of Crop Con- tents of each Bird in Grains. (December to March.' Average Weight, in Grrains. Apr. to Nov. Average. Deo. to Mar. Average. Com- bined Average for 12 Months. 6 a.m. 1 . . . . 10, 10 1 10 5i 7 „ 8 . . . . No specimen 8 No speci- men 8 8 „ No specimen . 20 . . . No speci- men 20 20 9 » 1,8. . . . 10 . . . ^ 10 Vi 10 „ 3, 18, 19, 4, 4, 20, 9 . No specimen 11 No speci- men 5i 11 „ 18, 2, 16, 27, 20, 14, 3, 13, 24, 40, 28, 36, 43, 34, 11 5 . . . 22 5 13i Noon. 12, 14, 2, 11, 18, 6, 7, 15, 21, 7, 1, 6, 15,24 120, 10 Hi 65 38 1 p.m. 18, 36, 62, 29, 32, 2, 3, 5, 13, 13, 18, 12, 19, No specimen 19 No speci- men 19 2 „ 26,45 . 70, 60, 20 . . 35^ 75 55i 3 „ 50, 173, 98, 213, 334, 27, 7, 12, 17, 26, 18, 14, 2, 6, 8, 28, 52, 24, 48, 31, 1, 5, 68, 31, 32 110, 100, 80, 180, 358, 200, 369, 50, 380, 250, 320 53 217 135 4 „ 15, 1, 4, 4, 246, 50, 17, 32, 50, 43, 50, 46, 8, 4, 2, 43, 3 339, 429, 239, 369, 429, 599, 280, 280 36 370i 208i 5 „ 8, 1, 1, 2, 1, 254, 66, 18, 5, 32, 23, 17, 7,23 150, 210, 200 . 32^ 1861 109J 6 „ 37, 93, 114 10, 349, 290, 20, 409 81 214 147^ THE FOOD OF THE RED GROUSE 81 but that full crops are more commonly found in birds killed in the afternoon and evening, both in winter and summer, than in the morning and forenoon. When a Grouse is in health the gizzard invariably contains food undergoing a grinding process throughout the hours of daylight, even in the longest summer day. The crop is often found very full towards evening, and rarely so before noon ; but this is only because in the evening the bird feeds more heavily in order to store up food for the hours of darkness, while during the daytime he seldom eats more than the digestive processes can deal with at the time. Hence during the early part of the day the food passes rapidly from the crop to the gizzard and on to the digesting tracts of the gut proper, and the crop is left almost empty. This has given rise to the view that Grouse only feed once a day, and that in the evening. Heather (Calluna vulgaris), as is well known, is the ordinary food of the adult Red Grouse. But twenty or thirty other plants are also eaten, often in great quantities, and it is a well ascertained fact that Grouse that have never set eyes upon a sprig of heather will live and flourish for years. Yet the importance of heather in building up the birds for the approach of winter cannot be exaggerated, and there is little doubt that in a bad heather year all the young birds suffer, while even in a good heather year the later broods will be permanently handicapped as regards physique and disease- resisting power if they have missed the best food months. The most noteworthy fact brought out by Table I. is that Grouse appear to require a larger quantity of food in the winter months from December to March, than in the spring, summer and autimm months from April to November.^ It is, of course, true that in a bad heather year Grouse may find substitutes for their staple diet. Of these substitutes blaeberry is undoubtedly the most valuable, as may be seen by reference to Tables II. and III. ; ^ but in many districts blae- berry does not grow upon the moors, and in no case is it so 1 Vide also p. 34. ^ Vide pp. 82 and 89. F 82 THE GROUSE IN HEALTH AND IN DISEASE reliable a winter food as good heather. Other substitutes for heather are rush-heads, crowberry, bog myrtle buds, seeds of Potentilla tormentilla, fern leaves, bog cranberry leaves, flowers of Erica telralix and Erica cinerea, moss spore capsules, sheep TABLE II. — Showing the Peecentagbs of Various Foods found in Chop Contents or Grouse prom April to November inclusive. Calluna (Heather) shoots, fresh and green , Calluna (Heather) shoots, brown but living . Calluna flower - buds, flower and seed-heads Blaeberry (F. myrtiUus), stalks and leaves . Various, including Erica, Crowberry Fern, Sorrel, etc. . April May 12 y82 12 Jane 12 July 27 Aug. 34 Sept. 16 Oct. 21 Nov. 24 15 172 33^ sorrel leaves and seeds, insects, and oats. On pp. 97-101 will be found a list of the vegetable foods eaten from time to time by the Red Grouse, with illustrations of some of the plants referred to. The summer substitutes for heather, while interesting as showing the wide range of the Grouse's diet when many varieties of food are available, cannot be considered of great importance to the health of the adult bird, for if the heather is good, and the supply sufficient, the stock will be well nourished and healthy even on a moor where there are no berries or other miscellaneous kinds of food. Heather, then, is the essential basis on which the Grouse depends, and the importance of the plant is so great that it may be permitted to give a short description of the phases through which it passes during the seasons of the year. Beginning with the months of early spring, it will be seen from Table II. that in April the Grouse's diet consists of an equal quantity of fresh green heather and of brown " winter " heather. The former is more nutritious than the latter, but PLATE XI, TYPES OF HEATHKR. Old Heather valueless :is fuud tui' (Jrouse. Yining short Heather valualile as f.io.l fur Grouse, Opposdc ji. S3. THE FOOD OF THE RED GROUSE 83 even the brown winter heather is better than nothing, and is to be distinguished from withered dead heather which Grouse never eat. The fresh green heather so desirable for the food of Grouse Short does not necessarily represent the young shoots of the spring heattierr^ growth, for these do not generally appear till May, but rather the evergreen foliage which the plant carries upon its lower branches throughout the winter. No one who casually examines a Grouse-moor in mid-winter can realise that the dull brown weather-beaten scrub conceals on its more sheltered twigs a luxuriant growth of vivid green shoots : these green shoots are far more numerous on short close heather than on the long overgrown heather so common on many moors, for as the plant increases in height it becomes more open in its growth and more susceptible to the blighting effects of frost and cold winds. In cases where the heather has attained a height of several feet the shelter is so greatly reduced that it is sometimes difficult to find any green shoots at all in winter unless the weather has been unusually mild ; such long overgrown heather is of practically no Value as winter food for Grouse (see PI. xi., Fig. 1). This type of long and apparently luxuriant heather is very common on the west coast of Scotland, and in many districts in the central Highlands, and probably accounts for the fact that these districts carry a comparatively small stock of Grouse. In other districts the heather seems to have developed a short, close habit of growth — ^to the uninitiated it would appear to be stunted and poor ; yet it is in the districts where this dwarf type of heather is common that Grouse appear to thrive in the largest numbers. The hills are covered with a close carpet of vegetation having a smooth level surface which may be compared to a well-clipped yew hedge — ^this level surface forms a canopy of shelter from frost, while the stems of the heather are so short and stiff that they are little affected by the wind. If this type of heather is examined, it will be found that immediately below the weathered canopy 84 THE GROUSE IN HEALTH AND IN DISEASE there is a rich growth of bright green shoots even in the most severe winter (see PI. xi., Fig. 2). There is no doubt that it is on the moors which have a large proportion of this short, close-growing heather that the largest stock of birds can be carried over the winter. But it is only on a special class of ground that this type of heather is found to grow naturally ; it is usually associated with dry, hard soil, good natural drainage, a rocky subsoil, and only a shallow layer of peat on the surface ; it is uncommon in districts with a heavy rainfall. Even on the best ground there is a tendency for the heather to grow too long and bushy ; but this tendency can fortunately be controlled by artificial means. In a later chapter the subject of heather burning is fully described,^ and it is only necessary here to state that, for purposes of food, heather ceases to have any value after it has been allowed to become rank. With the advent of May comes a great change in the condition of the heather plant. In this month every twig breaks out into green shoots, even the oldest and most ragged stick heather will produce young growth of the kind most valuable as food for Grouse ; but it is now too late for this tardy recovery to be profitable, for the days of famine are past, and there is sufficient food to feed ten times as many birds as there are upon the ground. Even in this month of plenty, however, the close, short heather of from 4 to 8 inches in height is superior to the straggly forest of overgrown plants, for there is an ever present risk of late spring frost when the tender young shoots will require all the shelter they can get. The appearance of the young growth is marked by an immediate change in the diet of the Grouse. On referring again to Table II., it will be seen that in May the consumption of fresh green heather shoots rises suddenly to 69| per cent., while that of the dry winter heather drops to 12 per cent. At the same time the proportion of miscellaneous foods is more than doubled, owing doubtless to the fact that every moorland 1 Fide chap. xii. pp. 343 et seq. THE FOOD OF THE RED GROUSE 85 plant is throwing off its winter sleep and bursting into appetising young buds. Just as the first flush of early pasture is more nourishing than the later growth, the first heather shoots of spring probably contain a larger percentage of nutritive food than at any other time of the year, and it is doubtless due to this cause that Grouse make such rapid growth in size and strength between the date of hatching in May, and the opening of the shooting season some ten or twelve weeks later. It is in the month of May also that the young heather plants first begin to appear on the black ground where the old heather has been burned. The length of time that elapses between the date of burning and the growth of the new heather varies. If the roots are not too old, and have not been destroyed by the fire, the new growth will spring from them within a year ; on some ground this always occurs. If, however, the roots have been burnt out, or are too old to send forth new shoots, the ground must lie waste for years, until a fresh growth of heather springs from wind-blown seed or from the seed lying dormant in the soU.^ It is usual to suppose that the first shoots of the young heather as they appear above the ground are greedily eaten by Grouse. Observation has shown that this view is not strictly correct, for the adult birds will never feed on the imma- ture plant so long as they can find plenty of close-growing heather of the type described on p. 83. This is fortunate, for otherwise the first growth might be very severely checked on a moor carrying a heavy stock of birds. Sheep, on the other hand, are very fond of the tender young shoots, and are often most destructive to seedlings which have not had time to secure a firm roothold. While the adult Grouse does not eat the very young heather, there is no doubt that the chicks prefer it to the shoots of the more mature plant ; but the amount eaten by them in the days of their infancy is so small that ' Vide chap. xii. p. 352. 86 THE GROUSE IN HEALTH AND IN DISEASE they cannot make any material impression on the growth of the plant. In June there is a continuance of the favourable food con- ditions which commenced in May. It will be seen by reference to Table II. that in this month the consumption of fresh green shoots of heather rises to 82 per cent., while that of brown winter heather drops to zero. In July^the consumption of heather drops to its lowest for the year — only 53 per cent. ; this is doubtless partly due to the ripening of blaeberries which occurs in this month. The consumption of blaeberry stalks and leaves has risen to 20 per cent., while the quantity of berries eaten is shown by the increase of " various " to 27 per cent. The unexpected increase in the consumption of brown winter heather is puzzling, but might be accounted for by an abnormal period of cold weather or blighting wind causing a "set back " in the new growth, and driving the birds to feed more largely on the old shoots- This view is supported by the fact that the birds have also eaten an abnormal quantity of blaeberry stalks and leaves, whereas in the following month, when the heather has presum- ably recovered from its temporary blight, the consumption of brown winter heather and blaeberry leaves and stalks drops at once from 47 per cent, to 1 per cent. The figures for July shown in the Table are probably exceptional, and do not repre- sent the normal proportion of foods eaten in that month ; but they are interesting as showing the elastic manner in which the Grouse can adapt himself to varying conditions. In August the figures for the consumption of heather appear to have become normal, and the fact that this is the great berry month of the year is shown by the increase of " various " to 34 per cent., the largest amount in any month. Berry feeding is, of course, irregular, for berries only grow in certain localities, their consumption cannot therefore be gauged by the examina- tion of specimens obtained from moors where no berries are obtainable. Berries are not an essential item in the diet of the Grouse ; but it is well known that where they are to be THE FOOD OF THE RED GROUSE 87 obtained Grouse will flock to them in large numbers often deserting the heather altogether for a while and congregating in vast packs upon the berry ground. The blaeberry fruit does not as a rule grow in such profusion as that of the clusterberry or Scottish cranberry, and does not seem to be so attractive to the Grouse, though its leaf and bud are much more generally eaten at all times of the year. The August figures are interesting as showing the first Heather indication of heather blossom in the diet. First in the bud, seeds^ afterwards in full bloom, and lastly in the form of fully ripened seed, the flower of the heather is an important item of food. There is an old saying that when the " stoor " {i.e., pollen dust) is on the heather in August a good Grouse season is sure to foUow, and the experience of the Conunittee tends to confirm this belief. In a year when the bloom is early and luxuriant the pollen rises in clouds when disturbed, covering boots and gaiters with a soft yellowish dust, and sometimes even inter- fering with the breathing of the dogs. This condition is usually followed by a fine harvest of well-ripened heather seed, and the importance of heather seed as a form of food may be seen at a glance from the figures given in Tables II. and III. It is often stated that in seasons when the corn has ripened well and early, the stock of Grouse in the following spring is healthy and vigorous, and the breeding season a good one ; from this it has been argued that the same weather which has resulted in a good crop of grain has also produced a good crop of heather seed. This factor, too, may have something to do with the difference in the numbers of Grouse which moors in different parts of the country are capable of carrying. It is well known that the number of Grouse on a moor does not depend upon the area of heather land, for in the thinly-stocked moors of the west of Scotland the heather growth is stronger than in the south of Scotland, where in many districts there is a larger stock of birds. Even in Yorkshire, Lancashire, and Derbyshire the groimd does not appear to be better suited for the growth of heather than in Scotland, yet in these counties 88 THE GROUSE IN HEALTH AND IN DISEASE the stock of birds is proportionately much greater. The differ- ence is partly to be accounted for by the fact already noted, that the heather in the north of England is of a better quality, that is to say with many more stalks to the square yard, than the rank growth of the west of Scotland, but it has also been suggested that in the former country the normal weather con- ditions are more favourable to the ripening of the heather seed. Again, in Caithness, where the grain always ripens well on account of the long hours of daylight in the summer months, the stock of birds which the ground can carry is unusually large. In September, October, and November, the tendency to revert gradually from summer to winter diet is well exemplified by the figures in Table II. Throughout these three months the consumption of the heather seed increases steadily, while " various " drops from 16 per cent, in September to 6 per cent, in November. In October we find the item of " brown winter heather " reappearing in the list, and in November we have a sudden increase in the consumption of blaeberry stalks and leaves, due probably to some temporary check suffered by the heather similar to that indicated by the figures for July. Wmter Turning to Table III. (p. 89) we find that in the four winter months the diet becomes more restricted. " Various " practi- cally disappears, and its place is taken by a larger quantity of heather shoots, while heather seeds and blaeberry stalks still keep their place in the list. One or two points are worth noting. In the first place, the sudden drop in the consumption of heather seed from 20j per cent, in January to 2| per cent, in February and 2 J per cent, in March is interesting as showing that once the seed has fallen to the ground it is no longer eaten by Grouse, though it may be valuable for the reproduction of the plant. Another point is that, both in this and the preceding Table, the figures relating to the consumption of blaeberry stalks and leaves are misleading because they are the result of averag- ing the crop contents of a large number of birds — many of them sent from localities where blaeberry is unknown. Were the THE FOOD OF THE RED GROUSE 89 crops of individual birds recorded it would be found that those coming from moors where blaeberry is common would show almost as large a consumption of that plant as of heather. Blaeberry forms as much as 30 per cent, of all foods taken by Grouse in Derbyshire, 22 per cent, in Yorkshire, 11 per cent, in Inverness and Dumfriesshire, and very little in any of the other counties. TABLE III,— Showing the Percentages of Vaeious Foods found in Crop Contents of Grouse from December to March inclusive. December January February March Per Cent. Per Cent. Per Cent. Per Gent. Calluna (Heather) shoots . Galluna (Heather) seed-heads . IT'} ««t (more than J ripe) (more than J ripe) 'ly™ %}"* Blaeberry stalks and buds (Vac- ciniwm, myrtillus) . 10 13i 16 ... Various, including Cowberry leaves ( Vaccinium viUs-idcea), Bog Cranberry leaves {Vac- cinium oxycoccus), Crowberry leaves {Empetrum nigrum), Erica, sorrel, fern, and other green leaves .... 3i 2i 7 i In special cases these averages are departed from, especially when the heather crop has been a failure. Thus, some Decem- ber specimens from Lancashire showed the remarkable average of 80 per cent, of blaeberry stalks and buds, with only 17| per cent, of heather shoots and 2| per cent, of heather seed, but in this case the heather-seed crop in Lancashire was reported as very bad. In the same year the heather seed crop in Peebles and Merioneth was reported as exceptionally good, and the December specimens from both these counties showed the proportion of 50 per cent, of heather shoots and 50 per cent, of heather seed, but no blaeberry. Probably the consumption of other foods, which are classed under " various," and have already been enumerated, varies 90 THE GROUSE IN HEALTH AND IN DISEASE Heather shoots the sole diet in Febru- ary and March. in the same way chiefly with local relative abundance, as, for example, in Perthshire, where " various " rises to 53 per cent. ; Ayrshire, where it reaches 47 per cent. ; and Derby- shire, where it reaches 40 per cent, of all foods taken. Individual taste plays a large share in the food statistics of Grouse. One may find, for example, one bird eating largely of fern leaf, another of bog myrtle buds, another of nothing but rush-heads or tormentilla seed. In one case, where two birds were killed with a " right and left " in a Grouse drive it was found that one had filled his crop with heather shoots, the other with blaeberry leaf buds, yet both birds had come oft the same beat. Occasionally one finds that even an adult bird has eaten scores of small black gnats. The flower of Calluna is varied occasionally by the flower of Erica tetralix, or ripe cluster berries, or spore-capsules of several mosses, or leaves of the cloudberry. The interest of Table III. centres on the first item, " Heather Shoots," for the figures prove conclusively, if proof were required, that, except on favoured moors where blaeberry abounds^, heather shoots and nothing but heather shoots constitute the diet of the Grouse during February and March — ^the fact that the February column shows 7 per cent, of " various " was due to one bird's crop being almost entirely filled with crowberry leaves, a quite unusual diet ; the " various " consumed by other specimens examined for the month only amounted to J per cent. It is obvious, therefore, that in February, March, and April the question of food becomes a critical one, for if the heather fails the Grouse must suffer either by direct starvation, or what is more dangerous, by being forced to crowd too closely on to the few small areas where good winter heather is to be obtained. Although we have no evidence from any one of the hundreds of Grouse crops examined that true frosted heather is ever eaten, the heather, which actually filled the majority of the winter crops varied greatly in its Value as a food. It could often be seen that the birds had been hard put to it to fill their THE FOOD OF THE RED GROUSE 91 crops at all, perhaps from stress of weather, or more probably because of excessive or deficient burning or an overstock of sheep, or for some other less obvious reason. The mere fact that the crops of many birds contain old heather is enough to prove that birds sometimes find great difficulty in collecting a meal of wholesome food. The vast majority of winter crops contain, as we have already said, good dark green or dark reddish brown winter heather, sound wholesome food with a minimum of dead woody tissue. But now and again one finds a crop full of old woody growth of which the food value must be very small. This is probably due to the fact that the moor has been left long unburned, and that all the heather within reach is old and rank. Or the moor may have been over-burned from every point of view except that of the grazing tenant. In such a case large tracts of young heather are burned again and again, often by runaway fires, to bring the land to grass and kill the heather. In this the grazing tenants of parts of the borderland and of the north of England have been very successful, and heather in many places is a thing of the past, the moors being now almost all white land. Scattered through this, where the tussocky grass has had its way for many years, is a thin growth of useless straggling heather of little value as food for bird or beast. For the purpose of drawing up Tables II. and III. two hundred and eighty-seven specimens of Grouse were examined, and the specimens were fairly evenly distributed over the months from April 1906 to March 1907. The specimens represented birds from no fewer than twenty-seven different counties, so that the results may be regarded as conclusive, so far as concerns the particular period under review. In case, however, of the period selected being abnormal. Table IV. (p. 92) was prepared to show the crop contents for two complete years, viz., 1906 and 1907. In this Table the figures for the corresponding months are placed together, and an average is struck for each month. It will be seen that these averages show the same general tendencies as are seen in the 92 THE GROUSE IN HEALTH AND IN DISEASE former Tables, and confirm the view that the figures given in Table II. for July and November 1906 were abnormal, and prob- ably due to exceptional circumstances. The total number of specimens examined for the purpose of drawing up Table IV. was four hundred and thirty-six, including the two hundred and eighty-seven already included in Tables II. and III. ; but in 1907 the specimens were not quite so well distributed as in the earlier period. TABLE IV.— Comparison op Monthly Averages of Crop Contents covering Two Years. Jan. Feb. Mar. Apr. May. Jun. July. Aug. Sspt. Oct. Nov. Dec. Calluna heather _ shoots . . j Calluna ■ heather flowerandseed- heads . Blaeberry stalk, bud and leaf . v. Various . . -{ 1906 1907 64 89 75J 72 97 81 93 64 81i 100 82 100 53 95 60^ 38" 63i 63 42 61 39 voi 54 59* Av. 1906 1907 76J 20i 10 73f ^ 9 89 78i 90J 0* 91 74 49| H 14 63i 16i 21 46^ 28 24 54| 33 56| 23 27 Av. 1906 1907 15^ 13: ■ ■ 5i 15 19 15 4 21 i 6 6 20 9i ■ 12 m ? 26 9 1 26} 22 10 25 21 10 Av. 1906 1907 6^ 2i 17 7 f 2 12i 3 15 3 12 3 12 10 27 5 6 34 36 2i 11 16 5 21 24 16 6 2 H Av. li H n 9 6 6 16 35 13^ 22i 3 ^ More food required in winter than in The results of this Table have also been given in the form of a chart for purposes of comparison.^ The strain upon the vitality of the Grouse in the winter months is intensified by the fact that a greater bulk of food is required by each bird per day than is required during the summer. 1 Fide p. 93. THE FOOD OF THE RED GROUSE 93 But few would have rated it at five times the quantity, and yet, from a comparison of the afternoon crops of the winter with those of the summer, this appears to be the case. Thus the average weight of food found in a Grouse crop from CHART SHEWING PERCENTAGE CONSUMPTION OF VARIOUS FOODS EATEN EACH MONTH BY THE RED GROUSE 100 95 SO 86 80 75 70 65 60 55 50 95 no 35 3.0 25 20 15 10 5 i- < < Oc 5 Oc X < z £ a. < ^ £ UJ Z -3 V) < 2 CD H a! UJ CQ o § i HEflrHCII TOPS fCai/um yufgarhj Hi/irHER FIOWCK fiNO secoHeADs (Catlufid i^ulgdris) BL/iEBlR»rsriM AND Quo (l^aca'nium myrlillui} VARIOUS W*, -9/ / \ J / \/ \ \ 7Sii J 75% \ 1 73 \ 7'^ \ 1 \ \ / \, A / 56h v V 5f'/4' 45% )/. Tf 26 ~ .26i'4 - -"f : '•' / ^ZZ-^s \ \ n 16 ■■18% fS^, ./i)S ^ ,^t 'in / 'ijh * / / ^ i5% \ S s /••> \-s.- .6' / s 354 / t •._ •■ir!-' ■3^.. ^^H w ■'■r'- \ 3— -3' =J2_ / X -2/^^ ■j... •5'/j. 94 THE GROUSE IN HEALTH AND IN DISEASE December to March, between 3 p.m. and 6 p.m., is 250 grains, whereas the average weight of food found in a Grouse crop from AprU to November, between 3 p.m. and 6 p.m., is only 50 grains. The fact that more food is required in winter to maintain the body temperature would, of course, partly account for this increase, even if the heather had the same food-value. But as heather certainly has an inferior food- value in winter, the amount taken must be increased in a far greater proportion. No doubt the necessity for provision during the longer hours of night- time has some effect in the overfilling of the crop in winter, but this would not account for crops being heavier in March, when the days are comparatively long, than in November when they are short. The interesting fact remains, and is amply proved by the figures, that more food is required by the Grouse in winter than in other seasons of the year ; and as in winter the pro- portion of Calluna to all other foods is as seven to one, it is obvious that a very great advantage accrues to a Grouse on a moor in which young and comparatively nourishing heather is abundant during the winter months, i.e., on a well-bumed moor, well covered with short close heather of a varying number of season's growth. To put this conclusion in other words ; whereas in summer a certain area of heather will support a bird comfortably, many times this area will be required for the same bird in winter, so that the capacity of a moor, as regards the question of stock, must be gauged mainly by its Grouse-feeding value during the winter months. If we consider this generalisation with reference to moor management we shall see that a moor carrying its full tale of birds in the summer becomes automatically and tmavoidably overstocked in the winter unless the stock is heavily reduced by shooting, for not only is there less food available, but the birds require a much larger quantity of food to keep them in health. THE FOOD OF THE RED GROUSE 95 Migration of birds in winter obviously complicates the question. In the case of a moor on high ground, which often loses all its birds in winter, probably natural conditions regulate the stock of birds automatically during spring and summer. But on the adjacent low-lying moors the case is more serious ; for the ground has to supply not only more food than is needed for its own stock in summer, but in addition an increased seasonal demand made upon it during the winter months by hundreds of undesirable immigrants from the higher ground. Such low -lying moors must always run the risk of being dangerously overstocked in the winter. In certain parts of the country oats form a regular seasonal Oats, change in the dietary of Grouse, and this form of food must now be considered.^ Very few birds with corn in any part of the alimentary canal were submitted for examination ; but so far as these specimens show, oats are an unsuitable form of food for Grouse. As is well known. Grouse often visit the stubbles and corn stocks in very large packs in the autumn — in September, October, or November, according to the season and locality. They seem to know that they are out of place, and finding themselves with a wealth of food all round, away from their normal surround- ings, are eager to fill themselves as full as possible in a very short space of time, aware, by instinct or experience, that they may be disturbed at any moment. One consequence is, as the examination of birds has shown, that they eat as much husk as grain, instead of picking and choosing, as Partridges do, in a quiet and leisurely manner. This difference in the crops of Grouse and Partridges that have been feeding on the same ground is very noticeable. The one is filled to repletion with indigestible and exceedingly irritating husks and a compara- tively small amount of grain, while the other (the Partridge's crop) contains grain only. The result in the Grouse is that the whole alimentary canal, from one end to the other, is soon in an irritable and inflamed ' Fide also chap. i. p. 29, and chap. iv. pp. 145 et seq. 96 THE GROUSE IN HEALTH AND IN DISEASE condition. The gizzard does what it can to work up the husks and grain into a milky paste, but the microscope shows that this paste is to a large extent composed of siliceous spicules and small spines of an almost glassy hardness. This damages the delicate mucous lining of the intestine. The result of the passage of this irritating food is, first, an extra flow of digestive juices, secondly, an increased activity on the part of the walls of the intestine, both as to movement (peristalsis) and secretion from the stimulation produced by this form of food. Thirdly, comes a point at which mucus is thrown out in large quantities to protect the gut, and this continues and increases imtil the actual cells themselves are shed, and the protection breaks down. Finally, the intestine becomes inflamed to the extent of ulceration, and this state will continue and increase so long as the cause continues to act. Such irritation to the intestine of even a healthy Grouse, which already has to deal with worms of at least two kinds, is bound to have an evil effect if continued for any length of time ; moreover, in places where the corn is left out owing to bad weather, or for other reasons, there is the additional aggrava- tion that the birds may be filling themselves with wet and sour grain, not one whit the less irritating as regards the husk, which cannot be softened by wet ; and no doubt the consequence of this is in some seasons noticeably bad. Corn in moderation is probably not unwholesome as a food, and were it possible to feed one set of Grouse with clean grain, and another with such stuff as the birds pick up for themselves on the stubbles, there is no doubt that the former would rapidly improve in condition, and the latter go steadily downhill. Such an experiment is not practicable. To recapitulate, the following maybe given as a fairly accurate account of the monthly dietary of the Red Grouse for the year :— January, Calluna shoots (64 per cent.) and Calluna seed- heads (27 per cent.). February, Calluna shoots (75 per cent.) and the stalks and buds of blaeberry and leaves of cowberry. PLATE XII, PLAK'l'S EATI'JN IIY THE (-1R0USE, Fic. 1. r, r. (';. v. i!i!ui ,jiii,1ilh!-< (lUai-lii.TLT— Wlinrtlei.erry— I'jilliiMTv— Whorts— Wliinberry) Ouoosilc V. 97.1 C. G. M. Fig. 2. Vacciiiiaiii orijcoccos (Cranberry — Mossberry). THE FOOD OF THE RED GROUSE 97 March, Calluna shoots (97 per cent.) and blaeberry stalks and buds. AprU, Calluna shoots (93 per cent.) and very little besides. May, Calluna shoots (82 per cent.) and rather more " various." June, Calluna shoots (82 per cent.) and " various." July, Calluna shoots (53 per cent.) and an increasing amount of " various." August, Calluna shoots (60 per cent.) and some Calluna flowers and " various." September, Calluna shoots (63 per cent.) and 16 per cent. of Calluna flowers and " various." October, much less (42 per cent.) of Calluna shoots, and nearly 30 per cent, of Calluna flowers, and some " various." November, still less (39 per cent.) of Calluna shoots, and 33 per cent, of Calluna flowers and seed-heads, and the rest " various." December, a rise in Calluna shoots to 60 per cent., but still 27 per cent, of Calluna seed-heads. List of Vegetable Food eaten from Time to Time BY the Red Grouse. Heather or Ling (Calluna vulgaris), the staple food of Grouse . Grouse eat the shoots, flowers, and seed-heads. See PI. XI., p. 83. Blaeberry {Vaccinium myrtillv^), known also as Whortle- berry, or Whorts Bilberry, Whimberry, Blueberry, or Blue Whortleberry. A low branched shrub 6 to 18 inches high, growing often in large green patches The flowers which appear in April, May, and June are flesh- coloUred, and the berries, which are black with a purple bloom, ripen in July and August ; they are agreeable to the taste. Grouse eat the stem, buds, flowers, and berries. See PI. xii., Fig. 1. G 98 THE GROUSE IN HEALTH AND IN DISEASE Cranberry (Vaccinium oxycoccus) known also as Bog Cran- berry, Mossberry, Moorberry, or Fenberry, a very low plant with a prostrate straggling slender stem and small leaves. It is found creeping on the surface of the moss in boggy places. The flowers which appear in June, July, and August are solitary and bright red, and the dark red fruit, which ripens in August, is pleasant to the taste. This berry is common in many parts of England, but is little known in Scotland, though the plant without the berry is sometimes seen. The leaf and the berry are sometimes eaten by the Grouse. See PI. XII., Fig. 2. Red Whortleberry or Cranberry (Scotland) (Vaccinium vitis-idcea), also called Clusterberry, Cowberry, Nutberry, or Nubbery, Craneberry, and Crawberry, a low, straggling shrub with leaves resembling those of the box. The pink flowers, which appear from June to August, grow in terminal drooping clusters, and the bright red berries ripen in September. Its leaves are to be distinguished from those of Arctostaphylos uva-ursi by the dots on the under surface and the rolled back edges. Grouse eat the berry eagerly, and will occasionally feed on the leaf. See PI. xiii.. Fig. 3. Red Bear Berry {Arctostaphylos uva-ursi), also called Gras- sack or Graashacks, a small trailing evergreen shrub which grows in dry heathery and rocky places. The leaves are finely reticulated, and the berries are red, and inside are mealy with hard angular seeds. The rose- coloured flowers appear from June to August in terminal clusters. See PI. xiii., Fig. 4. Cloudberry {Rubus chamcemorus), also called Averine and (in Cumberland) Noops, a small herbaceous plant belong- ing to the Raspberry family with large green leaves resembling those of the Geraniiun. It grows amongst the heather and grass on the mountain tops and high ridges. Its flowers, which appear in June and July, PLATE XIII. PLANTS EA.TKN BY THE (IROUSIv J.-. C. G. M. Fifi. 3. Vacciniinn rilis — Idica (Red Wliortlebciiy -Gliistcrlieirv) Cranbeny (Sivt.) Flo. -1. ArcfosfripJnjJos m-a-iirai (Rod Bfav Bcny — Graasliiielcs). c. a. w. Ojiposile p. 9S.] PLANTS EATEN BY THE GROUSE. C. 11. M. Fig. Ti. Jiiibus duima nivnis (Oluiidbcrry — Avtu'ine). C. G. .V. Fig. 7. Erica rincrca (Bull Heather — Fine-k-avuil Heath). Opposite [I. 99. J THE FOOD OF THE RED GROUSE 99 are white or rose-coloured, and grow on short erect stems, they are not unlike the flower of the Blackberry or Bramble, and its bramble-like fruit is red, turning to orange yellow as it ripens. The leaf and berries are eaten by Grouse. See PI. xiv.. Fig. 5. Bell Heather {Erica cinerea), also called Fine-leafed Heath, has leaves three in a whorl ; it grows on dry places and in similar situations to common heather. It flowers in July and August, and the bloom appears before that of the common heather. The flower bells are purple. The taste of the leaves is more bitter than that of common heather. The flower alone is eaten by Grouse, but while it is out it is eaten in fair quantities. See PI. xiv.. Fig. 7. Crowberry {Empetrum nigrum), also known as Crakeberry, Singberry or Blackberried Heath, a small prostrate plant with the habits of a heath. The purplish flowers, which appear in May and June, are very small and are placed in the axils of the upper leaves. The ripened berries are black. The top shoots, tight leaf buds, and berries are eaten by Grouse. See PI. xv.. Fig. 6. Cross-leafed Heath {Erica tetralix), has leaves, four in a whorl, and placed crosswise. It has rose-coloured flowers and grows in similar situations to common heather. Flowers in July and August. The flower-heads are eaten in quantities by the Grouse, but the leaf-shoots are avoided. See PL xv.. Fig. 8. Dwarf or Creeping Willow {Salix repens), a low, straggling shrub from 2 inches to 1 foot in height. Foliage and young shoots more or less sOky white. The plant has small oblong leaves, and bears small catkins in spring, followed by silky seed vessels. Found on sandy ground. Where it occurs the leaves and young shoots are greedily eaten by Grouse. Bog Myrtle {Myrica gale), also known as Sweet Gale, an erect shrub, 2 or 3 feet high, fragrant when rubbed. 100 THE GROUSE IN HEALTH AND IN DISEASE It has long, narrowish pointed leaves, slightly toothed- near the tip, and often downy beneath. It bears small catkins before the leaves are out. Always found in boggy places. Grouse eat the buds in winter and early spring, but sparely. Cotton Grass {Eriophorum), also called Cottonsedge, two or three species of similar habit. A rush-like plant, bearing in summer, after the flowering period, conspicuous, white, cottony tufts, either solitary or in clusters of two or three or more. Grouse are very greedy for the flower of this plant in spring, and the tender shoots are also said to be useful when they first appear. The plant is then known by gamekeepers as " Blackhead " or " Moss- crop." It is found in marshy ground. Sorrel {Rumex acetosella), Common Red or " Sheep " Sorrel. A slender plant, from 3 or 4 inches to 1 foot high, often turning red. It has long, more or less arrow-shaped leaves, very acid to the taste. The red-tinged green flowers are in terminal clusters on an erect stem, and are seen from spring to autumn. The plant grows in dry pastures, and on open heaths. The seeds are greedily eaten by Grouse. Heath Rush {Juncus squarrosus), a small rush about a foot high, growing in drier situations than most rushes. The flower and seed-heads are very freely eaten by Grouse. Field Wood Rush {Luzula campestris), a small rush with soft, flat, grass-like leaves, fringed with silky hairs. It grows in dry places. The flower- and seed-heads are eaten by Grouse. The following additional list of plants, upon which Grouse are said to feed, is given in a pamphlet on " The Improvement of Grouse Moors," by the Rev. E. A. Woodrufte Peacock, who has examined the contents of many crops and gizzards of the Grouse. Tormentil {Potentilla tormentilla). Suckling Clover {Trifolium miniis). PLATE XV. PLANTS EATEN BY THE GROUSE. C. a. M. FlO. 6. Em/irinii/i iiifirani (Crowbeny — Crakeberry). i\ c. M. Fic. 8. iV/«« /(V/'o/f'j' (Cioss-leaved Hcatlj). THE FOOD OF THE RED GROUSE 101 Heath Bed-straw {Galium saxatile). Marsh Lousewort {Pedicularis palustris). Heath Lousewort {Pedicularis sylvatica). Yellow Violet {Viola lutea). Bracken Fern {Pteris aquilina). The seeds of the following plants are greedily eaten, and are most useful as late autumn and winter food : — Mouse-tail Grass {Alopecurus myosuriodes). Purple Melio Grass {Molinea coerulea). Common Orache {Atriplex patula). Chickweed {Cerastium iriviale), and other moor cerastia. Persicaria {Polygonum aviculare, and P. persicaria), and Knot Grasses of all species. The flower-heads are also eaten. In their season, too. Grouse are very fond of capsules of the moor mosses, such as the Great Golden Maidenhair Moss {Poly- irichum commune), and the smaller fungi. Part II. — The Insect Food of Young Grouse based ON AN Examination of Crops and Gizzards. The Committee have devoted special attention to the question of the food of the Grouse in the earlier stages of its existence, and have examined the crop contents of many chicks with a view to ascertaining the nature of their diet. Their dietary is extraordinarily varied, and probably we have as yet by no means exhausted the list of what they eat. It was observed from the commencement of these investigations that young Grouse were much more addicted to insect food than were the adult birds, and in order to complete the Committee's knowledge on the subject it was found advisable to obtain the services of an entomologist. In the months of June and July 1908 the moors in Inverness- shire, Morayshire, and Banffshire, and at a later period those in Yorkshire, were visited with the following objects. (1) To obtain a number of young Grouse chicks and to 102 THE GROUSE IN HEALTH AND IN DISEASE examine the contents of their crops and gizzards, with a view of ascertaining both the nature of their food, and also, if possible, the intermediate host (supposed to be some insect or mollusc) of the Cestode parasites which infest these birds. (2) To identify exactly the various fragments found in the crop, proventriculus, and gizzard of Grouse by the careful collecting of insects on the feeding grounds of the young birds. In many cases the remains in the crop or intestine were so broken up and crushed that it was only possible to determine and name them after careful comparison with whole specimens obtained on the same spot.^ (3) To collect and put into spirit large numbers of insects and spiders for the purpose of dissection and microscopic examination for possible cysts of tapeworms. The birds were captured by hand and immediately killed by chloroform, dissected the same day, and their crops and gizzards transferred to methylated spirit. The contents of both crops and gizzards were afterwards examined, and the fragments carefully compared with whole pinned insects obtained on the same ground as the chicks. A detailed list of the contents of the crops and gizzards of the chicks was published in the Final Report of the Committee.^ The list of insects collected was most interesting, and included many rare species. Most of the specimens were collected on the actual feeding grounds of the young Grouse, and the list is therefore useful as showing the variety of diet possible during the first few weeks of the chick's life. On a typical Grouse moor by far the greatest variety of insect-life is found in the marshy ground around the sources of the streams. Diptera largely preponderate, but small Tineid Moths, May-flies, Stone-flies, and Spiders are also plenti- ful. On the higher and drier ground many other insects were ' A complete list of the insects obtained on the moors during the course of this Inquiry has been published in the "Annals of Scottish Natural History," pp 150- 162, July 1910. ^ " The Grouse in Health and in Disease," vol. ii. pp. 86-90. THE FOOD OF THE RED GROUSE 103 found, including Crane-flies, Bees, and the larger Lepidoptera, as well as a few others which must be regarded as of mere casual occurrence, such as Syrphidce or Hover-flies, the Bombus or Humble-bee, etc. The commonest insects in the crops are undoubtedly Diptera Inseots most eojn- of the family Limnomidce. Seventeen crops contamed speci- monly mens that could be referred to this family, and of these no ®^ ^^' fewer than fourteen contained the curious little species known as Molophilus ater. In one case there were over one hundred specimens of this fly. This bird was from eighteen to twenty days old, and its crop was gorged with the remains of the fly besides a few tips of heather. Other crops from the same moor, belonging to chicks a week old or less, contained fifty-six, fifty, thirty-four, and eleven examples respectively of the same fly. We may therefore conclude that the species is attractive to the eye and taste of the young chick. It was found plentifully in certain marshy spots where the chicks were known to feed. Although the results have been tabulated in various ways, it has been found difficult to trace any outstanding feature regarding the insect food of Grouse chicks. It is sufficient for the present purpose to state that the food of young Grouse is largely made up of insects, that these insects present a great variety of species, and that the species most commonly found in the crop is probably that which is most numerous in the area where the chicks are accustomed to feed. But it is also evident that the number of insects eaten shows a considerable falling off towards the third week of the chick's life. We should not expect the chicks to show much discrimination in the catch- ing of their prey, and as Diptera undoubtedly are the most numerous in individuals of all the insects on the moors, it naturally follows that they head the list in the table of crop contents. An attempt was made to ascertain to what extent the quantity of insect food decreases as the chick grows older, and a table was published in the Final Report which brought out the fact that after the second week of the bird's life there is a 104 THE GROUSE IN HEALTH AND IN DISEASE marked falling off of insect food and a proportionate increase in the vegetable diet.^ The crops are arranged, so far as possible, in order of age, beginning with the youngest. The ages of the birds are estimated by the length of the keel of the sternum or breast-bone, fbod^of ^'^ This table also showed that the crops of young chicks in chicks. the first week or two contain, in addition to insects, the follow- ing vegetable food-stuffs in varying proportions : — Calluna shoots ; only the very fresh young green shoots are eaten. Calluna flowers, in full bloom, and flower-buds. Moss fruit- capsules, or spore cases. Blaeberry flower-buds, and ripe blaeberries occasionally {Vaccinium myrtillus). Blaeberry leaves and young stalks. Fern leaves {Blechnum and Pteris). Rush- heads, in flower and seed {Juncus sq.). Tormentilla seed-heads. Shoots of Empetrum nigrum. Of these the most constant are the fresh young shoots of Calluna ; then the fresh blossoms of Calluna, and then the spore capsules of moss. While insects are commonly eaten, many crops of the youngest chickens contained no trace of them. It is practically certain that by eating some such animal food the cystic stages of the intestinal worms which infest young birds even in the first weeks of their existence are introduced. Until this matter has been further investigated, it is needless to say more here.^ Part III. — Water. There are various opinions regarding the Grouse's require- ments in the way of water. The majority of moor-owners and naturalists are firmly convinced that Grouse require water, and quote in support of their view the undoubted fact that when springs and drains are periodically kept open the stock is more healthy and numerous. Others state that water is not necessary, and that the fact that drains and springs are not allowed to become choked may have beneficial results ' " The Grouse in Health and in Disease," vol. i. p. 91. 2 See also cbap. vii. pp. 190 et seq. THE FOOD OF THE RED GROUSE 105 apart altogether from the maintenance of the water supply. The evidence on the subject is somewhat conflicting. As already stated, Grouse do not appear to require water from springs or burns in the earlier stages of their life ; ^ this fact is established from observations on both wild and hand- reared birds. On this subject, a well-known moor-owner in Banffshire writes : " Grouse never seem to want water except in a very dry season ; a shower is sufficient to last them for a long time. The less water they have in hand-rearing, I find, the better they do." And, again, " I have never noticed that the young Grouse, when half-grown or older, require more water than what they pick up in the grass in wet weather, and what is sprinkled on the grass or heather at meal times in dry weather. Old Grouse seem to know how much is good for them ; while young Grouse, if allowed access to water, are almost certain to drink too much, and scour. This, of course, refers to tame birds." Another correspondent of the Committee, a gamekeeper near Pitlochry in Perthshire, writes : " Regard- ing water, I have known several broods fetched out 600 yards from the nearest water of any kind, in a dry season, and they continued to thrive without water for at least three weeks after hatching, when rain would no doubt relieve the old bird, which I am of opinion had nothing to drink but dew all that time ; at least I never found young chicks without the parent bird along with them." On the other hand, a gentleman in Yorkshire, who success- fully reared twenty-four Grouse out of twenty-eight eggs set, says : " They were watered three times a day." And a game- keeper, whose experience of some of the largest moors in Perth- shire has lasted for a lifetime, says : " There must be water, and, where a moor is blest with good springs, there will the Grouse be also. One cannot have too many springs on a moor in dry weather." When full-grown there is little doubt that Grouse do drink ; hand-reared birds are seen to drink frequently on a hot day ^ Vide chap. i. p. 20. 106 THE GROUSE IN HEALTH AND IN DISEASE from the supply of fresh water provided for them, and the droppings of nesting birds are always found near water. Wild birds, in the hot weather of July and August, and in the dry, frosty days of winter, often congregate near running water and open streams when other drinking-places are dried up or frozen hard. It is well known that in the summer Grouse often shift entirely from the drier beats of a moor to the well- watered ones, and, on a certain dry, sandy moor near the sea, even the young birds die if the artificial drinking-pools are allowed to run dry.^ The almost unanimous opinion expressed by correspondents favours the view that under natural condi- tions the adult Grouse go to drink two or three times a day. In support of the view that Grouse either never drink, or at least are not dependent upon a supply of drinking water, several arguments are brought forward. It is said that no Grouse has ever been seen to drink, but when we consider how wild the bird is in its natural state this is not surprising ; indeed, only very few observers have succeeded in seeing the bird in the act of feeding. Another argument used is that from an examination of the alimentary canal no trace of water can be found, and the contents of the crop are always found to be dry. This may be sufficient to prove that the bird does not drink when the crop is full, but does not dispose of the possibility of its drinking during the long periods of the day when the crop is empty. Then, again, cases are quoted of moors which carry a large and flourishing stock of Grouse where the ground is by no means well watered. On one of the best stocked Grouse moors in Britain, the only water comes from about a dozen springs and one deep burn which runs through the middle of the ground. Grouse are seldom observed to resort to the bum, and it is difficult to see how several thousand birds can all water at the springs. While it cannot be said that this entirely disposes of the question, it seems to justify the view that Grouse are not dependent upon a large water supply, How far dew forms a substitute for water is a matter which ' See note on p. 317. THE FOOD OF THE RED GROUSE 107 has received considerable attention without any results being arrived at sufficiently definite to be worth reporting. There is a curious lack of information available regarding the fall of dew, the districts in which dew is most prevalent, etc. There is probably a close connection between dew and the infection of Grouse by the nematode worm Trichostrongylus pergracilis. In view of the fact that the larvae of this worm can only climb the heather shoots, or indeed exist on them, when they are slightly damp, it would appear that this is one of the questions which might be further investigated with advantage.^ Part IV. — Grit. The health of Grouse and of other game-birds is greatly dependent on the nature of the grit they take to assist in the assimilation of their food. During the autumn of 1906 the Committee made a collection of the grits from the gizzards of Grouse and other game-birds. These grits were obtained from the gizzards of Ptarmigan from Ben Mohr in Sutherlandshire ; Grouse from Ross-shire, InVerness-shire, Aberdeenshire, and North Wales ; Blackgame from Ross-shire and Exmoor ; and Partridges and Pheasants from various counties in England and Scotland. The gizzards of Grouse naturally received most attention ; but for purposes of comparison those of other game-birds were also examined. The quantity of grit found in a single gizzard varies very slightly. Samples taken from adult cocks were each found to be equal in bulk to an ounce of shot, although, of course, much lighter, and the number of grains in each ranged from three hundred and fifty to five hundred and fifty. It was also noticed that, especially in the case of Pheasants, the cock birds have a larger quantity of gritty material, while the individual grains also appear to be larger. This is doubtless correlated with the larger size of the bird, for in the smaller varieties of game - birds and in immature individuals it is ' Fide chap. viii. p. 235. y '^ '' ' ' - 108 THE GROUSE IN HEALTH AND IN DISEASE invariably found that the grains of grit are fewer and smaller than in the larger and full-grown specimens. The gizzard of a Grouse chick of fourteen to twenty days old was examined, and the grit was found to weigh 3 grains. It consisted of frag- ments of quartz, smooth and water-worn, and evidently picked up in the bed of a stream. Two minute but perfect prisms of quartz, were also found. All the grains were decidedly smaller than in an adult. In a half-grown chick the grit weighed 58 grains, while in adults the average weight is 118 to 120 grains. Grits are present even in very young birds ; in one case they were found in a chick only forty-eight hours old. The grit of an old bird can be at once recognised by the large size of the grains, and by the excessive polish and smooth- ness of the well-worn surfaces, suggesting that the larger grains are in use for a considerable period of time. Between extreme youth and old age all stages of wear and polish may be found, ^ as well as every gradation in point of size. Constitu- A full analysis of the petrological character of the speci- gn . j^gj^g jg contained in the Interim Report of the Committee ; it is unnecessary to repeat all the details here, but a short summary of the general conclusions may be given. As would naturally be expected the constituents of these samples are nearly always hard rocks and minerals. Minerals or rocks softer than quartz, fiint, or felspar are hardly ever found ; this may be due partly to selection by the bird, but it must also be borne in mind that soft substances would soon be ground up by the action of the gizzard, and disappear. To this also is probably due the almost complete absence of any calcareous matter, which is both soft and comparatively soluble. The only really abundant constituents in the gizzards of Grouse are quartz and felspar, and small fragments of various rocks com- posed of one or both of these minerals, such as granite, gneiss, quartzite, etc., with occasionally grains of shot and crystals of garnet, and other minerals. Felspar is chiefly found in specimens from Scotland and North Wales, where rocks con- sisting largely of this mineral are specially abundant. The THE FOOD OF THE RED GROUSE 109 specimens from Ross-shire are of interest from the geological point of view, since in some cases they contain a representative collection of the gneissose and schistose rocks of the north- west Highlands. A comparison of results shows that in the gizzards of Grouse quartz is nearly always present, although no quartz may be found on the moor where the bird was shot. Two cases of this may be mentioned. On one part of an extensive shooting in^North Wales there is excellent feeding and sheltering ground for Grouse, but no quartz grit, yet the gizzards of the birds always contain quartz ; in order to obtain it they have to fly across a wide valley to another hill, and then return again to their feeding-ground. Again, on a Ross-shire moor no quartz could be seen on the moor, yet all the gizzards of these birds contained quartz ; this quartz was probably obtained from the burns, for on examining them small pockets of quartz were found in many of the pools and eddies. The quartz is not always angular and sharp, but is frequently water-worn ; in these cases it is probably picked up out of burns - — in fact, in low-lying moors the water courses are almost sure to be the source of this quartz. The grits found in the gizzards of Yorkshire Grouse are very similar to those of the Scotch birds except in one case, where the grit is chiefly composed of small black pebbles. In one gizzard out of every three of the Grouse examined shot were found ; but shot were rarely found in the gizzards of Pheasants. It may be noted that whereas Ptarmigan and Grouse seem unable to exist without quartz. Partridges, and still more Pheasants, are more adaptable ; they prefer quartz if they can get it, but failing quartz. Pheasants will content themselves with flint, sandstone, and even coal. Doubtless the tough and fibrous nature of the food eaten by Grouse makes it necessary for him to confine himself to the hardest and most angular descriptions of rock, and even when quartz grits are found in the gizzard the angles are often rounded and smooth from the nature of the work which they have been called on to perform. 110 THE GROUSE IN HEALTH AND IN DISEASE Flint grit may serve for Pheasants, but it does not fracture into serviceable shapes for Grouse. Sharp points and cutting edges are not wanted, but sub-angular and roughly rounded pebbles of small size for the breaking up and pulping of the comparatively hard foliage of Calluna. In another part of this Report it is suggested that when quartz is scarce it might be artificially introduced with a view to the welfare of the stock. This expedient has met with some success, but has not been very extensively adopted. The artificial introduction of quartz grit has frequently been tried with Pheasants, and always with success. In the Committee's collection there are several specimens of gizzards from Pheasants shot on estates both before and after the introduction of quartz, and in every instance it can be seen that the quartz is preferred to the natural grit found on the estate. Observations have been made with a view to finding out how long quartz or other hard grits normally remain in the gizzard of a Grouse, and it has now been proved by experiment that if none are supplied to make good the normal and presum- ably accidental loss, the bird whose gizzard may on the first day have allowed about a hundred grits to pass, becomes exceedingly careful on the second and third day, and allows no such loss to occur again. In a case in which no grits were supplied to a Grouse at all, and in which the Grits passed in the droppings were carefully washed out and collected every day for twenty-one days, the greatest daily loss after the second day never exceeded thirteen small pieces, even though a hundred and sixty pieces had been passed on the first day, and twenty-seven pieces on the second. This bird died unexpectedly on the twenty-first day, and upon dissection the gizzard was found to contain still no less than half of the original contents, all of which had been in the gizzard for at least three weeks. That this apparent control of the gizzard over the loss of grits was not merely accidental was proved by the occurrence of a precisely similar series of losses day by day in another bird ; but when its companion died, apparently as the result of losing half THE FOOD OF THE RED GROUSE 111 its grits, the second bird was not pressed to a similar finish. It is therefore probable that in the ordinary course of a Grouse's life the daily loss of small grits is considerable, and that this loss is replaced by an equally regular supply picked up day by day upon the sides of moor roads, or in " scrapes," or along the channel of a burn. But, in the event of a heavy snowfall it appears very probable that the Grouse soon recognise that the loss is exceeding the amount which can be made good day by day, and that in such a case they can, in some unexplained way, place a check upon further loss. It cannot for a moment be imagined that the bird has any sort of voluntary control over the passage of grits from the gizzard. But it is quite conceivable that the gizzard itself will allow a certain careless loss of any surplus number, especially of the smaller pieces, so long as there is still a suffi- ciency of larger grits in the gizzard. When the supply, however, is straitened, and the bird fails to find more grits to swallow, it may be that less food is eaten as well, and thus the loss of grits is automatically reduced. This is probably the explanation which comes nearest to the truth, and it is a significant fact that a bird not only loses weight, but may actually die when only half of its normal supply of gizzard grits has been lost, and when the dejecta show that this amount of grit is still capable of grinding up the food given to it. Under normal conditions the character of the grit required differs with the nature of the food that is being eaten. Heather, oats, and oat husks are all efficiently dealt with by the quartz grit normally found in a Grouse's gizzard, but large hard seeds are not, and are passed undigested. These seeds are sufficient in themselves to pulp fruits so long as fruits only are being eaten. But as soon as heather or other fibrous vegetable matter is eaten, quartz or other stone grit becomes essential. In the Blackcock the gizzard with its quartz pebbles can crush hawthorn pips, but the Grouse apparently cannot crush any of the pips of eVen much smaller berries, such as 112 THE GROUSE IN HEALTH AND IN DISEASE Clusterberry, Blaeberry, or Crowberry. They all pass through intact. The possibility has been suggested that the replacement of quartz grits by hard seeds of fruit, and the passage of the former through the intestine may act as a vermifuge. So often has a diet of berries apparently arrested a case of Helminthiasis that it is a question to be seriously considered whether enough attention is given to the encouragement of berry-bearing plants upon a moor. In many cases the sheep keep them so closely cropped that except where there are woods or enclosures it is difficult to find a visible trace of them. It would perhaps repay the trouble and expense to fence oft enclosures from the sheep where any tendency is seen for the growth of Blaeberries, Cranberries, Crowberries, or the like, and the Grouse would quickly find and make use of them. It is particularly unfortunate that during deep snow, when Grouse have great difficulty in replenishing their stock of gizzard grits, they are compelled by hunger to feed upon the very foods which most rapidly evacuate their entire stock of grits. The hips and haws wliose large, hard seeds, as has been said, quickly replace the quartz in their gizzards, are com- paratively useless to them for dealing with heather or Blae- berry shoots, yet the bush and tree fruits are amongst the first emergency rations used in a heavy fall of snow, since they come within reach as the ground foods become more deeply buried. The strongest evidence that quartz is the most suitable form of grit is its universal presence in all the vegetable feeding birds that can obtain it. Red Grouse, Ptarmigan, Black- game, and Capercailzie, as well as Pheasants and Partridges bred on the moor borders, and Scandinavian Willow Grouse, all collect quartz, and nothing but quartz, if it is by any means to be obtained. PART II.—THE GROUSE IN DISEASE CHAPTER IV CAUSES OF MORTALITY IN THE RED GROUSE In classifying all diseases it must be remembered that before a disease can be scientifically named it is necessary to ascertain whether the disease in question has an individuality which can be specifically described and recognised by definite character- istics and symptoms. It is an accepted rule of medical science that the primary cause of a disease should be sought for as the first step towards the discovery of a remedy. Yet this important rule has been almost wholly ignored by the majority of writers upon " Grouse Disease," with a few notable exceptions. Hardly a writer on the subject but dwells on vague gener- alities, hopelessly mixing up observed facts with speculative theories, and primary with predisposing causes ; for instance, if the chief object of the writer of the following paragraphs had been to confound an already almost hopeless confusion, he could hardly have been more successful : " What I stUl maintain is that the unwholesome food which Grouse have been compelled to eat has occasioned both the worms with which they have been infested and at least one type of the disease." " The disease appeared in all its virulence after the heather had been damaged by hard frost ; but the crying evil is un- doubtedly the overstocking of the moors with sheep." " Grouse have materially suffered from cold late springs which have blighted the heather." 113 H 114 THE GROUSE IN HEALTH AND IN DISEASE " Granting as I do that this nasty little parasite Strongylus does occasion disease in Grouse, is there anything illogical in attributing the cause of the worm to the bird being compelled to eat unwholesome food, from its natural food the heather being damaged or destroyed from continued blighting east wind ? And thus the blight of the heather is really at least one cause of ' Grouse Disease.' " " Insufficient or unwholesome food is the cause at least of one type of disease amongst Grouse." Or the following : — " ' Grouse Disease ' is caused mainly by overstocking, over- preservation, and the complete and indiscriminate slaughter of certain species of so-called vermin, notably the Peregrine Falcon ; also by the state of the young and old heather after severe and late frosts which do much more harm now that heather-burning is done systematically. Also by greed for big stock. Unnatural and rapid burning of heather and a wholly artificial state of Grouse farming ; also interbreeding." In the above quotations, which may be perfectly sound so far as they go, we have a very fair summary of possible pre- disposing causes ; but the immediate cause of " Grouse Disease," whether we consider the disease to be Pneumonia, or Strongy- losis, or Coccidiosis, or Enteritis, or any other sickness in the world, is not touched. Until, therefore, we have discovered the active agent in a disease we cannot say that we know its cause. This is a funda- mental rule, and to be satisfied with predisposing causes is to be satisfied with less than half the truth, though that half is, of course, very important if our intention is to proceed further in the attempt to discover a remedy for the disease in question. The primary or acting cause of Klein's acute infectious pneumonia was believed to be a bacillus known as the Bacillus coli ; the primary cause of Cobbold's Strongylosis is the thread- worm Trichostrongylus pergracilis ; the primary cause of Grouse Coccidiosis is Eimeria (Coccidium) avium, and so on ; not east winds or the absence of the Peregrine Falcon. CAUSES OF MORTALITY IN THE RED GROUSE 115 The consequences of what has appeared to be epidemic disease amongst Grouse have been so disastrous from time to time in the past that it is not surprising to find a very widespread tendency amongst sportsmen and gamekeepers to attribute every death and every case of sickness on the moor to the so-called " Grouse Disease." It has been the object of the recent " Grouse Disease " Inquiry to investigate this question, and to find out amongst other things : — (1) Whether the sickness described universally as " The OWeots of ^ ' •' "Grouse Grouse Disease " in all the literature of the past century which Disease" deals with the subject is, in truth, a single disease with individual characters peculiar to it alone ? (2) Whether a distinction can be discovered between various recorded outbreaks of the so-called " Grouse Disease " which will justify the opinion held by many writers that two distinct forms of disease, due to two distinctive causes, are confused under the one term ? (3) In the event of a finding in favour of the belief in two or more distinct epidemic diseases, what are their respective causes and effects, and by what distinctive titles and characteristics should they be known ? (4) In the other event of a finding in favour of the belief that only one epidemic disease exists, is Professor Klein's view right, that the only serious disorder amongst Grouse, to which all past records of disease refer, is the one which has for its cause a Bacillus, and for its chief characteristics the appearance of acute pneumonia in the lung, and " all the characters of an acute infectious epidemic disease " ? Or, (5) is Dr Cobbold's view right, that there is a pseudo-epidemic disorder amongst Grouse, answerable for all the recorded out- breaks of disease, which has for its cause a thread-worm, and for its chief characteristics certain damage to the gut, due to chronic irritation, leading to extreme emaciation ? (6) Is there any other form of " Grouse Disease " capable of causing extensive mortality, which has hitherto been overlooked ? These are questions which have to be answered before it can be said that we understand the forms of " Grouse Disease " 116 THE GROUSE IN HEALTH AND IN DISEASE Results of Com- mittee's investiga- tion. Minor dis- eases of Grouse. sufficiently to classify them systematically. With a view to defining the main divisions under which the next chapters are arranged, it may be well at this stage to give in anticipation a brief summary of the conclusions at which the Committee has arrived. The Committee is of opinion : — (1) That the sickness which has in the past caused " Grouse Disease " among the great majority of adult birds is a single disease with clearly defmed characteristics of its own ; (2) and (3) it follows that if the two forms of " Grouse Disease " hitherto described as distinct diseases are, in fact, one and the same disease, there is no longer any need to differentiate between them ; (4) that " Grouse Disease " is not due to an acute infectious pneumonia caused by the presence in the lung of Klein's Bacillus ; (5) that adult " Grouse Disease " is caused by the presence of Cobbold's Trichostrongylus in large numbers in the caeca ; (6) that another form of disease in Grouse exists which has hitherto escaped notice. This disease is caused by the presence of Eimeria (Coccidium) avium in the alimentary tract, and is referred to in the following pages by the name of " Coccidiosis." It is improbable that Coccidiosis can have been responsible for any of the outbreaks of so-called " Grouse Disease " in the past, for, so far as the Committee's experience extends, it is only the chicks that succumb to this disease, whereas the records of " Grouse Disease " refer only to mortality among adult birds. The grounds on which the foregoing conclusions are based form the subject of several long and technical chapters in the Final Report of the Committee, but in the present volume it is not proposed to do more than give a general description of the two principal forms of " Grouse Disease," viz., Strongylosis or "Grouse Disease" proper which kills the adult birds, and Coccidiosis which kills the chicks, We have still to discuss the less important diseases of Grouse, of which quite a considerable list may be given, though their interest is greater from an academic point of view than as a serious menace to^the well-being of a moor: indeed, with one CAUSES OF MORTALITY IN THE RED GROUSE 117 or two possible exceptions, there is not much probability that they will ever give cause for much anxiety. The exceptions occur most commonly in consequence of the proximity of Grouse moors in certain districts to low ground shootings heavily stocked with Pheasants and Partridges. It is well known that these latter birds are often the victims of various forms of Enteritis, and cases have been reported of Grouse dying of disease apparently contracted from Pheasants which have strayed on to the moor. Amongst other causes of death may be mentioned diseases connected with the reproductive functions, diseases connected with the seasonal moults, and diseases caused by deficient or unwholesome diet. But apart altogether from mortality due to disease, a large other number of dfeaths are directly or indirectly due to accident or mortality. to artificial causes. Many of these causes may be traced to the agency of man, and it will be shown elsewhere to how great an extent some of them are avoidable by attention to the details of moor management. Shooting, in all its forms, is responsible for a great deal of unrecorded damage amongst Grouse ; and the examples of " pricked " birds which have come to the Committee's notice, generally sent as " diseased " birds for examination, show amongst other things how extraordinarily active is the re- cuperative power of an animal in a state of nature. Bones are fractured and reunited, even those of the wing, allowing the bird to survive, to be shot again the following year. Peritoneal adhesions may shut off a perforation of the intestine, and even result in a short circuit of the gut before leakage has caused sufficient general peritonitis to result in death. The present chapter deals with the mortality and damage due to accidental causes or to natural causes other than true " Grouse Disease," and thus clears the way for the proper consideration of the more important subject dealt with in the subsequent chapters, viz., death due to " Grouse Disease." 118 THE GROUSE IN HEALTH AND IN DISEASE The causes of death and damage to Grouse not due to " Grouse Disease " may be classified as follows :— (a) Those referable to artificial conditions, such as accidental consequences of sport, wire-fencing, telegraph-wires, sheep- drains, vermin-traps, poison, etc. (6) Those referable to natural conditions, such as Extremes of climate ; cold, heat, wet, snow, etc. Destruction by birds and beasts of prey, so-called " vermin," and by the pugnacity of the Capercailzie and Blackgame. Exigencies of reproduction : fighting of cocks, over-sitting of hens, egg-binding, gastro-uterine gestation, etc. Exhaustion due to moult, and to skin disease affecting the growth of feathers. Deficient diet and starvation, due to frosted, blighted, and over-age heather or to heather-pests ; deficiencies of grit and water ; excessive or injudicious burning ; and feeding on unwholesome foods, e.g., corn-stooks and sour grain. A. — Causes of Death and Damage resulting from Artificial Conditions. Under this heading there are some causes which may be passed with a mere mention. One might do so with all, perhaps, were it not for the interest attaching to some of the cases which have come under observa- tion, and the light which they throw on the recuperative power of birds in the wUd state. Some of these cases occurred in birds which had died naturally ; in others the specimen had been shot, and forwarded for examination as a possible case of disease. The following accidents are within the experience of most game preservers : collision with wire fences and telegraph wires, accidental damage from vermin traps, snapping by sheep dogs, drowning in sheep drains or moss-cuttings, etc., and wound- ing by shot. And of these no one can doubt that the " pricking " of CAUSES OF MORTALITY IN THE RED GROUSE 119 birds due to bad shooting is the most frequent cause of damage. The following examples illustrate a number of these points : — A hen Grouse whose wing had been cut off clean at the Collision shoulder, presumably by collision with a wire fence, not only ^**^ '^"^■ survived to be shot the following season under suspicion of being a sick bird, but actually succeeded in rearing a brood of five healthy young Grouse. Another instance of precisely similar nature is recorded, in which the bird, a hen Grouse, had successfully raised a brood of healthy chicks notwithstanding the loss of a wing. In the first of these cases the wing was cut off so close to the body that no vestige of a stump was left. The cicatrix in the skin was adherent to the tissues about the rounded end of the broken hxmierus, of which only the head and neck were left. There was every appearance that the wound had healed well and quickly, probably some four or five weeks before the bird was shot, and soon after the nesting time. In feather and in con- dition the bird was not appreciably the worse for her mishap. The shoulder-blade, which had been broken in two pieces at the time of the accident, had made a strong though irregular imion {see Fig. 1). For the purposes of comparison a drawing is given of the bones of the undamaged (right) side of the same bird (see Fig. 2). The sternum or breastbone is another bony part also liable to injury, but sometimes without immediately fatal results ; in such cases damage is most probably caused by collision with wire fencing. A hen Grouse was picked up alive on a Berwickshire moor in August. She weighed only 14J ounces, and was very thin and in very poor feather ; but upon dissection it was found that, perhaps a month or two before, she had broken her breast- bone right across by collision with something — probably a wire fence. The smaller hinder portion had been displaced forwards and upwards, riding upon the larger portion, and there becoming fixed firmly by osseous union, but with a considerable 120 THE GROUSE IN HEALTH AND IN DISEASE amount of displacement and shortening. This accident must have completely disabled the bird for six weeks or a month, Fraetored end of / left humerus eiaviele Fig. 1. A permanently fractured left humerus and a fractured and re-united left shoulder blade. Fig. 2. The same bones uninjured from the right side of the same bird. rendering her quite unable to fly. Yet she had lived, and the broken bone had united. The only apparent disability CAUSES OF MORTALITY IN THE RED GROUSE 121 remaining was the infestment with parasites, the tapeworms, Hymenolepis, and Davainea and the round - worms Tricho- strongylus having all established themselves in excessive numbers in the various portions of the gut. Thus Strongylosis would have eventually killed the bird, but only indirectly and as an after result of the injury, which in itself was cured. A young Grouse chick, 11 1 ounces, very plump and well feathered, was found dead in Argyllshire, in August 1908, and was forwarded for examination. There was no sign of disease, the bird was in excellent condition, and death had re- sulted from collision, prob- ably with wire fencing, which had broken the breast- bone right across. There was hardly any external sign of damage in this case ; but on removing the skin the bruising and bleeding which overlay the more serious damage beneath at once in- dicated the cause of death. It is easy to distinguish between damage before and after death, when it is re- membered that the circula- tion is active in the former case and inactive in the latter. Any violence done before death is accompanied by bruising and bleeding. Damage done after death may be accompanied by post-mortem staining due to the leakage of bloody serum ; but will never show blood-clots lying under the skin or amongst the muscle-sheets or other organs. Two cases of fractured sternum have occurred in Blackgame, forwarded for examination. The first represents a recent fracture of the sternum in a Blackcock. The second {see Fig. 3) represents almost exactly the same damage reunited, Fig. 3. The breastbone of a Greyhen fractured and reunited. 122 THE GROUSE IN HEALTH AND IN DISEASE Fis. 4. View of the right side of Fig. 3. owing to the fact that the Greyhen, in which it occurred, did not die until some months after the accident. The exact method of overriding and union of the broken bone in this example is shown in Figs. 4 and 5 which give a view of the breastbone from each side. Both cases oc- curred in a very curious series of six deaths in Blackgame which were forwarded for examina- tion as cases of "Grouse Disease," all coming from the same locality. The facts were as follows : — (No. 1.) A Black- cock, October 16th, 1907 ; weighing 45 ounces ; was found dying ; in excellent condition. Had been feeding on corn. (No. 2.) A Greyhen, October 26th, 1907 ; found dying, thin, in poor condition, dirty beneath, and much bedraggled ; had evidently been squatting for a long time on the ground, unable to fly. This bird was forwarded by train for examina- tion, and on arrival was still living. She was kept alive, feed- ing freely on grapes, until November 2nd, when she was killed with chloro- form, as there appeared to be some internal damage with a complete absence of any sign of disease. On post-mortem Fia. 5. View of the left side of Fig. 3. CAUSES OF MORTALITY IN THE RED GROUSE 123 examination the breastbone was found to have been broken right across near the abdominal end; but it had since become firmly united again with a little displacement due to overriding of the hinder fragment (see Fig. 6). Clearly this bird was unable to fly because the wings from long disuse had become weak, and adhesions about the pectoral muscles probably made the attempt to use them painful. The joints of the legs too were stiff and difficult to straighten, the result of long squatting on the groimd amongst wet undergrowth. She must have led a sedentary existence for some time, and would probably have died without regaining the power of flight. .Fibrous Union Fig. 6. Showing method of union of broken breastbone. There can be no doubt that the cause was collision, probably with a wire fence. The organs showed no sign of disease. (No. 3) A Greyhen, weighing 34 ounces, was found dead in good condition ; had been feeding on corn. Examination showed that an old wound had produced extensive bleeding in the abdomen, but so long previously that the clot was semi- organised and formed a series of concentric blood-cysts. A more recent damage had caused extensive bleeding around the base of the heart and into the lungs, and this had killed the bird ; but not until several hours had elapsed since the accident. 124 THE GROUSE IN HEALTH AND IN DISEASE which almost certainly resulted from collision with a fence. There was no sign of disease. (No. 4) A Blackcock, weighing 41 ounces, was found dead on November 1st, partly picked by crows or mice, but in fair condition. It had been feeding on hawthorn berries. This bird had a deep wound in the breast, from an accident which had broken the lower end of the sternum. The damage was un- doubtedly the result of collision with a fence, or something of the kind. It was exactly comparable to that in the Greyhen, No. 2, but more severe, so that the bird died shortly after the accident. No sign of disease was discovered. (No. 5.) A Blackcock, weighing 39 ounces, was found dead in good condition on November 4th. There was no food in any part of the gut. This bird had its back broken, and the bone splinters had torn the lungs and the smaller air passages, so that they gradually filled with blood. The hinder part of the bird's body and its legs must have been paralysed, so that it could not search for food, and the drowning of the bird in its own blood took so long to kill it that all the food, eaten before the accident, was digested and the remains passed. The whole . body was full of venous blood, showing that twelve or twenty- four hours may have elapsed between the accident and the bird's death, which was due again almost certainly to collision with a fence. Once more there was no sign of disease. (No. 6.) A Greyhen, weighing 31 ounces, was found dead on November 4th in good condition ; again the back was broken, but this time lower down at the level of the last rib instead of at the fifth rib as in No. 5. The left lung was compressed and rendered absolutely useless by a large blood-clot which had collected in the thorax owing to internal damage caused by the splintered bone. This bird had evidently lived for some hours after the accident, and had previously been feeding on corn. There was no sign of disease, and every reason to suspect collision with a fence as the cause of the accident. Obviously this series of deaths was not due to an epidemic of disease, though it is difficult to understand why so many CAUSES OF MORTALITY IN THE RED GROUSE 125 birds should have coHided with fences in the same locahty, where no new wires or other obstructions had been recently- erected. The gamekeeper's view at first was that they all had disease, and outward appearances to some extent supported him. Later on, however, the Blackgame began to leave the valley where they had been feeding on corn, and where the accidents occurred, and once more took to the moors. The keeper reported that the Blackgame on the moors were quite healthy, and continued : "I have been among Blackgame and Grouse for over forty years, and I never saw Blackgame affected the same way. If eating green oats is killing them, they have eaten them for over forty years and were not a whit the worse. I have known Blackgame eat oats from September to December, and not a single bird die from it. What puzzles me is why they are not dying in the next valley (3 miles off). When the Black- game light on the ground they tumble on their heads. If there is a fence hard by they sometimes fly into it. I have seen many birds (recently) showing the same symptoms." All this suggests some form of intoxication, and it is just possible that the sodden and half rotten grain eaten by the birds might produce sufficient alcohol by fermenting in the warmer process of digestion, to act upon them in this way. There is, of course, also the possibility that grain soaked in spirit had been purposely put down, but in this case it was improbable. It was certain, at anyrate, that the epidemic was an epidemic of accidents and not of disease, however suggestive appearances may have been to the contrary. Sometimes a collision or other accident may cause fracture of the vertebra or internal injury. A hen Grouse, of 20 ounces, was " found dead, but quite warm, about a mile from the nearest part of the moor, and at a place to which Grouse never go unless driven off the moor, by storm, which very rarely occurs," This was in Cumberland in March 1909. The bird was quite healthy, in good condition, well feathered, and of a fair weight, and having been found dead with feet and legs well featheredj^was just the kind of 126 THE GROUSE IN HEALTH AND IN DISEASE bird to be classed as a case of " the acute form of ' Grouse Disease ' which kills off birds in splendid condition before they have time to waste." But there was some blood in the mouth, and when this clue was followed up by further dissection the root of both lungs was found to have been torn to pieces by splinters of bone from the fracture of two or three vertebrae. There was a fair number of Trichostrongylus in the caeca, but no sign of disease and no tapeworms. A cock Grouse of 26 ounces was forwarded from Scotland with the correspondence quoted below. The case affords an excellent example of the evidence upon which the idea of an acute and very rapidly fatal form of " Grouse Disease" has been founded. The gamekeeper writes as follows : — " I am herewith sending you a Grouse cock which, I think, must have ' gapes ' or something. His neck is very much swollen. This is the third bird of the kind I have seen during the season. We are now seeing diseased Grouse, at least birds having all the appearance of such. In fact, taking all over I never saw worse feathered birds than those we get here. They are especially poorly feathered on the legs." This was written at the end of September when the birds were in full moult. This particular bird had still the old claws on, and two primaries of each wing to shed ; and the feet, though apparently unfeathered, were on closer inspection just beginning an excellent growth of feathers. One of its eyes was damaged. Attached to the bird was a note saying that it was a diseased Grouse, notwithstanding that it was making a healthy moult for the winter, and weighed 26 ounces. On dissection the swelling of the neck was found to be due to a mass of loose blood-clot ; the thorax also was full of blood-clot, and the bruising and tearing of the blood-vessels about the root of the neck left no doubt that the bird had met with an accident. There were no tapeworms in the bird at all, and no sign of disease of any sort. And though the caeca contained a good many Trichostrongylus, there was no redness, and the mucosa was quite healthy. CAUSES OF MORTALITY IN THE RED GROUSE 127 A cock Grouse of 21 ounces was " watched for ten days " in March 1908. During that time he was flushed regularly every day by the gamekeeper at the same place. But during the last few days he could not be flushed " without the help of a dog as he was becoming every day the weaker " ; so he was shot, and forwarded as a case of " Grouse Disease." This he was, but only to a very slight extent. The real reason why he objected to being flushed regularly every day was because he had retired to a certain retreat to be away from other birds and remain quiet while a wire-fence wound healed. It was found that the wire had torn through the skin of his breast, and had rent the pectoral muscles, which are the muscles of flight. Had he been left alone he would have recovered in a few weeks, and would have rejoined the healthy birds on the higher ground as soon as he was fit to hold his own. This retirement of a sick or damaged Grouse to a place where he can recruit his health in solitude is in accordance with the habit of almost every animal that lives. Damage to the crop is sometimes responsible for accidental Damage to death or injury. °''°P' A cock Grouse of 21 ounces was caught and killed, July 1908, in Argyllshire. There was very great dilatation of the crop, which was filled with an old blood-clot and with heather, the crop contents had been there for a long while, and had become dry and mildewed. There were two or three cicatrised wounds through the skin and crop ; but these were all closed except one,- which remained open and suppurating. The passage to the oesophagus downward was free, and the bird might possibly have recovered in time. The crop was adherent every- where to the subcutaneous tissues, and so to the skin, and there were numerous enlarged blood-vessels wandering over the crop wall and also in the adhesions caused by the diffuse inflammation. It is extraordinary that the bird should have maintained its weight so well — 21 ounces ; Davainea was absent, Hymenolepis and Trichostrongylus were both present, but with no redness in any part of the gut. 128 THE GROUSE IN HEALTH AND IN DISEASE Damage to wing. Figure 7 represents an example of recovery from a fracture of one of the wing-bones in a cock Grouse. The radius in this case had been broken in two at the junction of the middle and lower thirds, probably from a shot wound. The bird must have lived for at least a month or six weeks during the winter without flying, but made a perfectly sound union notwithstand- FiG. 7. Broken and re-united wing-bones. Fig. 8. ing. It survived to be shot dead on the wing in April as a healthy bird killed for purposes of crop analysis. Another instance may be quoted of the radius being broken in two pieces at about its centre, probably by shot. In this case the union was incomplete when the bird was killed ; but, though some movement was possible between the broken ends, the formation of callus and new bone had made a considerable advance towards effecting a firm union. Figure 8 represents a firmly united fracture of the radius which had been broken in two about the centre. There was no CAUSES OF MORTALITY IN THE RED GROUSE 129 evidence of damage to the ulna. A shortening of 2 mm. (from 50 mm. in the sound bone to 48 mm. in the damaged one), occurred in the united radius, and the union was effected irregularly with a large boss of new bone. This bird was an undersized hen, killed as a " piner " on August 15th, 1906, Excessive fhiekening or Fibula ImpaefeA ^hot- FlG. 11. Fio. 9. Fig. 10. Brokeu and re-united leg-bones. and suspected of disease. She was shot on the wing, but was in very poor condition and badly infested by Davainea, Hymeno- lepis, and Trichostrongylus within, and by innumerable bird- lice and other parasites without. Figures 9, 10, and 11 all resemble one another in representing Damage to united fractures of the upper third of the tibia and fibula, ®^' °°®' 130 THE GROUSE IN HEALTH AND IN DISEASE In each case the fracture was comminuted. The shortening in one leg was from 83 mm. to 76 mm. The union in each was effected by an irregular and immovable mass of bony matter thrown out to include the fibula which is also greatly thickened. The first case {see Fig. 9), was that of a cock bird which lived to be shot on January 7th, 1907, weighing 20 ounces. Eight femur from two points of view. Normal left femur. Femur with bony growth. Fig. 12. Pig. 13. Fig. 14. Broken and re-united thigh bones. Fig. 15. The fractured end of the bone had been rendered smooth by absorption, and the deformity caused by overriding of the lower fragment had been partly obliterated. In another case {see Fig. 10), the upper fragment was united to the lower at an angle of 30 degrees. Figure 11 was obtained from a cock, found dead in November 1907, having succumbed to Strongy- losis. The shot which caused the damage can be seen to the left impacted in the bony mass. CAUSES OF MORTALITY IN THE RED GROUSE 131 Two cases of damage to the femur may be mentioned : — Figures 12 and 13 show a united fracture with shortening from 55 mm. to 43 mm. owing to the excessive displacement of the lower portion of bone. The upper fragment forms an angle of 45 degrees with the lower. The bird was a hen found dying from Strongylosis in April, but the fracture must have taken place at least six weeks before. From the complete union effected the- bird must have been healthy at the time, but the accident may have been the starting-point of sickness, which resulted eventually in its death. Fig. 14 shows the undamaged femur of the same bird. Figure 15 shows a bony outgrowth of the femur due to periostitis resulting probably from some violence which was insufficient to break the bone. Damage from internal shot wounds also occurs. An adult Internal cock Grouse of 16 ounces only was found in Nairnshire in wounds. September 1909, sick and unable to fly. It was a bad case of Strongylosis ; but the original cause of its sickness was a number of lead pellets which had some time previously passed through the pectoral muscles, the sternum, and the liver. In another case an adult cock Grouse of 18 ounces, in good feather, was found in Yorkshire on September 5th, 1908, sick and unable to fly. The bird was suffering from Strongylosis ; but there were also healed scars of shot wounds. The lungs were somewhat stained post-mortem, but one of them was thick and solid. It was in part a dark, rich, reddish black all through, and in part normal pink. A line of adhesions joined up the second and third lung-lobes, and there were cicatricial puckerings showing where a shot had passed through. The solidification was due to old bleeding. A shot had also recently passed through the neck, traversing the muscles, and tearing a small hole in the trachea, which had remained unhealed. There was bloody fluid in the mouth and trachea. The skin wound had nearly mended, but bits of feather were found in the tissues of the neck, and the scar outside was matted up with broken feathers. The wound made by the shot 132 THE GROUSE IN HEALTH AND IN DISEASE which passed between the ribs and entered the lung had completely healed, and its position was shown under the skin only by a small blood clot which persisted. This bird -must have survived its most recent wounds for a week or two at the least. In October 1909 a cock Grouse of 20 ounces was sent for examination from Perthshire in very good condition. The following information was sent with the bird : — " I enclose a Grouse which I picked up to-day. I put up a pack of Grouse. This one rose a little after the others, and after flying about 200 yards dashed to the ground, and when I got up to it it was quite dead and blood flowing from its mouth." Examination outside before opening revealed the fact that the bird had been pricked by shot. One of the quill feathers was cut through, evidently by a pellet, and there were marks of shot in other quills. Blood was flowing from the mouth, and an examination of the lungs showed that one of them had been torn by shot so that many of the air-passages were full of blood. But the blood liberated by the original wound had clotted in the lung and saved the bird from immediate death. Had the bird been allowed to rest until this lung and its clot had healed and become firmly cicatrised it would perhaps have recovered. Instead, however, it was flushed and forced to take flight. This broke down the freshly formed clot, and the bird died of secondary haemorrhage. There was in addition to this a very large clot round the liver, showing that a pellet had entered this organ also. This case is a very good example of what has certainly been described in former years as the sudden death of birds from acute disease, a disease which strikes them down in the pride of health in full flight and excellent condition. It is also a very remarkable case of long survival after serious damage caused by shot wounds. Another case was that of an adult cock Grouse of 19 ounces, found dead on January 8rd, 1908, in Argyllshire. This bird had been badly sprinkled with shot some time CAUSES OF MORTALITY IN THE RED GROUSE 133 before its death — at least a couple of months, judging by appear- ances. That it should have survived at all is extraordinary. Three shot pellets were found lodged in the tissues of the neck ; two ribs had been broken on each side, and had firmly united again. There were small caseous masses in the lung, the remains of small localised abscesses which had been caused by the passage of the shot. The pleura were fastened to the ribs by traumatic adhesions ; and as the result apparently of some obstruction or damage to the usual set of veins there was a great enlargement of what are generally quite insignificant veins in the wall of the proventriculus. On February 17th, 1908, a cock Grouse of 23 ounces was found dead in Inverness-shire. It was in excellent plumage and condition, and although an abundance of Strongyles was to be found in the caeca there was no redness and no engorge- ment of the villi. The cause of death was apparently collision in flight, and the chief damage was that suffered by the heart, which was much enlarged and swollen out to twice its normal size by a great extravasation of blood in the muscular tissue of the walls, both of the auricles and ventricles. The veins running in the wall of the proventriculus were much engorged. The lungs were unhurt, and otherwise the bird was perfectly normal. A hen Grouse of about 17 ounces was found on July 23rd, Tumours caused 1909, in Sutherlandshire, sick and unable to fly. She was in by shot very poor condition, and heavily worm-infested. But the chief °"° ' cause of distress was a very large tumour caused by rupture of the vessels in the inner walls of the gizzard. The gizzard was enormous, and occupied nearly the whole of the abdominal cavity, causing complete compression of most of the intestines intensified by the formation of adhesions due to peritonitis and the stretching of the normal mesenteries over the tumour. The tendinous and tougher portion of the gizzard had retained its normal size and shape, but the fleshy part had become greatly distended.. The tough lining membrane was the part which had given way. 134 THE GROUSE IN HEALTH AND IN DISEASE Damage to feet. Damage to bill. Cases have been occasionally observed of dermoid cysts and fibroid tumours in the neck ; these may sometimes be the result of shot wounds. Various accidents may happen to the foot and metatarsus of the Grouse, ranging from complete loss of the foot at the tibio-metatarsal joint to the loss of toes at the meta- tarsophalangeal joints, or at the various inter-phalangeal joints. Steel vermin traps will perhaps account for some of these cases, but in one case the appearance of the stumps of toes on both feet, to a different extent on each foot, suggests frost- bite as the cause ; or at any rate some form of gangrene rather than steel traps. A possible explanation is the strangulation of toes, sometimes even of feet, which sometimes occurs in infancy by the tightening of strands of sheep's wool accident- ally wound round them. This is a common accident with Lapwings.^ An instance of the death of Grouse in a vermin trap may be recorded. Two healthy cocks fighting in the spring accidentally came together into a " Samson " trap, and were simultaneously kDled. Damage to the bill may sometimes be a cause of death. A cock Grouse of 18^ ounces was found dead on July 13th, 1908. There was a very little Calluna heather and Blaeberry leaf and stem in the crop. The bird had probably found difficulty in obtaining sufficient food for the lower bill was split and curved, forming an unhandy instrument for plucking heather. Death by starvation, however, had been hastened by Helminthiasis. Davainea was abundant ; Hymenolepis filled the duodenum, while Trichosirongylus was present in great numbers. This bird would very probably have recovered during the summer but for the additional handicap of its damaged bill. It had survived the two months of highest mortality, April and May. ' A similar case, occurring in a hen partridge, shot when flushed with the covey, is described in the " Field," September 12th, 1908. CAUSES OF MORTALITY IN THE RED GROUSE 135 Many interesting cases have also been recorded of recovery from flesh wounds, either by shot or by barbed wire, and the following have come under the notice of the Inquiry: — One case represented a long standing leakage of the crop, due to a woimd through the skin and crop-wall. Owing to constant use of the crop, and to the alternate distention and contraction of the overlying skin, the adhesions between the edges of the skin and crop-wall had become permanent before there was any chance of the openings in either being closed^ Bits of heather pressed constantly between the lips of the wound had prevented healing, and had defeated the efforts made by the crop to pass all the food into the gizzard. The bird had therefore to eat more than the normal amount to make good a chronic wastage, and this accounts for the very abnormal distention of the crop which often characterises cases of the kind. Such cases may have resulted from shot wounds, or from rents made by barbed wire. The latter is probably the cause in the majority of cases. It is fairly common to find shot pellets loose among the contents of the crop or in the gizzard. They have sometimes been lodged there when the bird was killed, but have more commonly been picked up and swallowed as grit, or out of simple curiosity. In one case a shot pellet was actually encysted in the thin wall of the crop. It would have found its way eventually into the crop without any damage ; but it is curious that a pellet having entered the bird with sufficient impetus to get through the skin and half way through the wall of the crop should not have gone right through into the contents. The danger to young chicks in sheep drains and in moss Danger of cuttings for " peats," or for general surface draining, has already ^rams. been mentioned. It is greatest during a " spate " after a spell of dry, hot weather in June or July, when young broods have been led by their parents to take shelter from the sun in dry drains with steep sides. The sudden filling of these drains is responsible for the loss of many chicks before they find a place to scramble up into safety. This danger is well 136 THE GROUSE IN HEALTH AND IN DISEASE recognised, and the best method of avoiding it is dealt with elsewhere.^ Accidental Accidental poisoning is a rare cause of death in Grouse. poisoning. ^ £^^ cases have been brought before the Committee as cases of " Grouse Disease." It is not easy to guess how poisoning occurs, for poison used in killing vermin is administered mainly in eggs, and in the carcasses of fur-bearing animals, neither of which are likely to be tampered with by Grouse. Poisonous sheep-dip has been blamed in some cases ; but it is difficult to believe that it can be more than the rarest cause of accident. The theory that many Grouse are poisoned by lead pellets, whether swallowed as such, or in solution as carbonate of lead in drinking water, has been ingeniously upheld by an elaborate calculation of the amount of shot scattered over a moor in a shooting season ; but though the crops and gizzards of Grouse do occasionally contain a lead pellet or two, they are sufficiently uncommon to be a matter of curiosity to the finder rather than a cause of sickness to the birds.^ The following is an account of what was supposed to be accidental poisoning of Grouse by sulphate of Barium. It is given by Macpherson in the " Fauna of Lakeland." ^ Quoting John Borrow as writing from Alston in 1837, he says : " In consequence of the Grouse in some parts of this neighbourhood having been unable to procure sand (owing to the depth of snow), they have picked up particles of the sulphate of Barites, which appears to have been the cause of a very great mortality among them. A person whom I can depend on assures me he saw not less than forty brace dead upon the moors a few days since." One may, I think, legitimately wonder whether this mortality was not due rather to grit - starvation, accompanying and augmenting the evils of food starvation, which is always present to some extent with deep snow, ^ Vide chap. i. p. 17, and ohap. xii. p. 369. 2 Fide MiaionaXi, " Grouse Disease," p. 160. 3 Vide Reverend H. A. Macpherson, "A Vertebrate Fauna of Lakeland," p. 323. Edinburgh : D. Douglas, 1892. CAUSES OF MORTALITY IN THE RED GROUSE 137 No case of poisoning in Grouse can be attributed to the con- sumption of any plants found growing upon a moor. Several cases of abscesses and septic poison of the leg, Abscesses which resembled " bumblefoot " and " whitlow," were sent up poison, for examination during 1908. A young cock Grouse that was shot purposely on August 25th, on account of the condition of its body and feet. The foot of another Grouse was affected in the same way though to a less degree. The latter weighed 15J ounces, and its condition was fair. Both feet were much swollen with collections of caseous pus. It was killed " on an exceptionally dry juniper hill " in Inverness-shire. There were no abnormalities in any other part of the bird, except the usual infestment of Trichostrongylus ; but the organs were all apparently healthy. Several similar specimens were obtained upon the same moor. It is evident that in Grouse, and in poultry affected with " bumblefoot," we have the result of localised suppura- tion from septic infection following upon some small and unnoticed wound or damage such as a scratch or bruise. A " whitlow " is exactly coijiparable to this affection in the toes, and a whitlow may be a septic affection of the superficial or deeper tissues, and if of the latter, the infection may spread to tendon sheaths, or even into the joints themselves, or between the muscles. B. — Causes of Death and Damage resulting from Natural Conditions. Nearly all the causes of death and damage due to purely natural conditions have from time to time been so well described that it will here suffice merely to recapitulate them.^ ^ In connection with the effect of weather conditions upon Grouse, much additional evidence has been collected by the Committee, and is referred to in other chapters of this book. In view of the information now made available for the first time, it may become necessary to reconsider some of the opinions of recognised authorities referred to in this chapter. 138 THE GROUSE IN HEALTH AND IN DISEASE Climatic 1. Climatic extremes are well known and well recognised, ex remes. They may occur from the time the eggs are laid to the end of the bird's life. At every age, in every season, and every year, the welfare of the bird is threatened by unusual climatic conditions in one direction or another. Excessive heat and its usual accompaniment, water famine, are both somewhat uncommon at the time of year when they would be most dangerous to Grouse life. They are referred to in chapter i.i The following abstracts sum up the harm ascribed in the past to wet and cold, Macdonald in " Grouse Disease " has no doubt about the matter when he writes that " Damp and cold never fail to produce diarrhoea, cramp, and disease " ; and again, " Excessively cold or wet seasons are succeeded by great mortality among birds, and Grouse suffer more in wet than in dry seasons, however cold— this was strikingly demons- trated in the wet season of 1872-1873 " ; and again, " Cold wet causes bad hatching seasons." ^ So also Macpherson in the Fur and Feather Series says that young Grouse " do best in fairly dry seasons," ^ And for the bp,d effect of cold and wet on the food supply Macdonald, again, in " Grouse Disease," says : " We can also connect the disease with wet seasons. The heather does not quite ripen, particularly the small tops on which Grouse chiefly feed," * There seems, in fact, to be a consensus of opinion amongst those who have had the best opportunities for judging, that the hatching season can hardly be too dry so long as there are dewy nights. The chicks can supply their needs by drinking dew in the morning, and beyond this they find sufficient moisture in the insects and young succulent moss-capsules and heather shoots which form their staple diet, and which contain something like 60 to 80 per cent, of water. The sitting hens want water and must have it, and their bulky droppings may always be found 1 Fide chap. i. pp. 104-106. " Macdonald, "Grouse Disease," pp. 24, 40. ^ Fur and Feather Series, "The Grouse," p. 24. * Macdonald, " Grouse Disease," p. 40. CAUSES OF MORTALITY IN THE RED GROUSE 139 on the edges of the burns and springs nearest to their nests. They are reported to suffer seriously in a drought. But when all is said, excessive heat and drought are far less to be feared in the British Isles than excessive wet and cold. Sunstroke, " staggers," and " splanders " in wild birds of any kind are extremely rare when compared with the results of an exces- sively wet hatching season, especially if it happens to be accom- panied by cold. Too much wet is undoubtedly more harmful both to the sitting hens, to the eggs, and to the young birds when hatched, and for a month at least after hatching, than any other climatic extreme to which Grouse are subject. Exces- sive rainfall is said to account for the scarcity of Grouse on the moors of the West of Scotland and of the Western Isles, and to this John Colquhoun adds that " Grouse are never so plentiful on the west coast, from the wet springs addling so many of the eggs." And again, " Protect as strictly as possible, and kill every rapacious bird and beast on the ground, there never could be half as many Grouse reared in the west as in the north or centre Highlands ; and the reason is the humid climate pre- vents it. Every sportsman knows that the Grouse in the north or centre Highlands of Scotland are immensely more numerous than in the watery west." ^ The nesting season of 1906 was most typically a bad wet season everywhere, and in walking over some of the Scottish moors, south of Perth at any rate, nest after nest was found to be deserted with a full clutch of eggs in which the chicks had died just before the time of hatching. Second broods are in such cases no doubt produced, but if an early winter sets in, or if the autumn turns wet and cold, these late-hatched broods swell the ranks of the poorly-feathered, undersized birds which appear next spring as " piners," and are liable to succumb eventually to disease of one sort or another. The question of the diminished value of second broods is fully discussed in a later chapter.^ 1 Colquhoun, "Moor and Looh," vol. i. pp. 194-198. ^ Chap, XT. pp. 335 et seq. 140 THE GROUSE IN HEALTH AND IN DISEASE In every way, except in checking the growth of the heather, hard frosts and heavy snow do less harm than excessive rains. A certain number of hens may be occasionally frozen to death upon their nests, as has been recorded by Stuart-Wortley (Fur and Feather Series). Eggs, too, may be " frosted " when late frosts are sufficiently severe,^ or young Grouse may be killed by late snowstorms, as in 1864 on Glenshea ; but such occurrences are very rare. The power of resistance of the egg to frost is dealt with in another chapter.^ Still, however little direct harm excessive cold may do to Grouse, the indirect harm is often very great, and there is no doubt that late frosts in the north of England and in the south of Scotland, catching the heather after the sap has begun to rise, often reduce the available supply of food. "Frosted It may be well to review what has been written from time to time as to the effect that " frosted heather " is supposed to have upon the Grouse. In Macdonald's " Grouse Disease " a Scottish forester is quoted as having stated that during a certain epidemic there was no " Grouse Disease " all along the sea coast where the heather does not suffer by frost, while ten mUes or so inland, where the sea ceased to exercise its influence, " Grouse Disease " began. It is there stated that the dissection of Grouse that had died of the disease proved that their crops contained frost-bitten heather.^ And, again, in a quotation from Colquhoun's paper, it is stated that in Perthshire, in 1852 and 1853, the heather was excellent, and in consequence there was no disease, while in 1854, 1855, and 1856 the heather was frosted without snow, and there was bad disease. Again in 1857 the heather was excellent, and there was no disease ; and so on.* Speedy, however, says: "Heather which has been killed by frost and entirely divested of its nutritive qualities 1 W. A. Adams, "Twenty-six Years' Reminiscences of Scotch Grouse Moors," p. 94. London : Horace Cox, 1889. ^ Vide chap. i. pp. 10-14. * Maodonald, "Grouse Disease," p. 40. * Ihid., p. 122. CAUSES OF MORTALITY IN THE RED GROUSE 141 is about the most unlikely thing for Grouse to feed upon." ^ He says, too, that after bad disease there are more survivors on the high exposed heather-frosted parts of the moor than on the lower sheltered localities, and that " ' Grouse Disease ' has not been peculiar to those seasons when the heather was most generally frost-bitten, or when it had not been covered and protected by snow. . . . Some of the most fatal visitations have been preceded by winters more remarkable for mildness than severity." The statements contained in the above quotations from Macdonald and Colquhoun are probably due to a misuse of the term " frosted heather," for there is a condition of heather which is not rightly called " frosted heather," and it will prevent misunderstanding if the meaning of the term is clearly defined. To begin with, young, fresh, green heather of the early summer may be caught by a late black frost which sweeps over the moor and literally " scorches " it red. This is a comparatively frequent occurrence in the north of England, and was well ex- emplified on a certain Yorkshire moor in the early summer of 1907. The countryside was green one week, and " as red as a fox " the next. Every leaf that was turned red by the freezing winds (there was no snow) died, and eventually dropped off without recovering. But the plant was not killed ; it very soon put out fresh leaves from the lower stalks, and the moor in a few weeks was as green as ever. Still, the fact remains that the birds of that moor were suddenly reduced from a very abundant to a very limited supply of food, for in no case will a Grouse eat such useless stuff, nor has a Grouse's crop ever been found to contain this fox-red frosted heather. It is dead, and the birds know it and will not eat it, but forthwith proceed to look for something that is not dead, therefore any harm that accompanies its appearance is due, not to the presence of unwholesome food, but to the sudden shortage of wholesome food. Such fox-red frosted heather must on no account be ^ Tom Speedy, "Sport in the Highlands and Lowlands of Scotland,'' p. 202. Second Edition. Edinburgh and London : William Blackwood and Sons, 1886. 142 THE GROUSE IN HEALTH AND IN DISEASE confused with the dark, red-brown, winter heather, which is secure from any ordinarily severe frost, and is merely the resting condition of the healthy living plant. The two are totally distinct in colour, the former being, as has been said, brick-red or fox-red, and the latter a deep brown, or dark reddish brown often associated in the leaves of the other side of the twig, with a deep or vivid winter green. Such heather is alive and healthy, and forms perfectly wholesome food for the Grouse ; it is, in fact, their staple winter food. The only point is that being somewhat dry and sapless (in which lies the whole reason of its immunity to frost), and lacking in food-value when compared with fresh, young, summer heather, about three or four times as much has to be eaten by the bird to get the same amount of nourishment. This dark, winter heather cannot be correctly called " frosted," since the change in it is merely due to a seasonal alteration in the chemical condition of the cell contents, while it remains in the healthy resting winter state. With certain modifications it may be stated generally with regard to the two forms of " frosted " heather that in one case the heather is dead — having been killed by even a moderate frost — and that in the other it is living, and is proof against even a severe frost. The presence or absence of snow on the ground makes a great difference in time of frost. Snow acts as an efficient protection to the heather, and only the extra long twigs that protrude beyond the snow are affected by frost. Hard frost after snow trims the heather by cutting off and killing all the longer pieces, so that the leaves bleach whitish grey, and eventually drop off. This may happen even to straggling pieces of dark brown winter heather if the frost is severe enough; but it requires a very low temperature and a pro- longed exposure to affect real winter heather to any great extent. There is no other condition of heather which can with any show of reason be called " frosted " ; and it may be urged that no heather should be so named except that which has been nipped and killed beyond all chance of recovery. To call CAUSES OF MORTALITY IN THE RED GROUSE 143 the resting condition of winter heather " frosted " is as un- reasonable as to call any evergreen shrub " frosted " because its winter leaves are darker in colour than those which it pro- duces in early summer. Closely simulating the fox-red, frosted heather, however, is the heather damaged by a certain beetle known as Lochmcea suturalis. This pest has long been recognised in Argyllshire, Ayrshire, and Dumbartonshire, and its ravages were described by Mr Grimshaw in 1898.^ This subject has been fully dealt with in a later chapter.^ Before leaving the climatic causes of death and damage to Heavy Grouse, something remains to be said about heavy snow. Its most obvious danger lies, of course, in starvation, since a heavy snowfall, unaccompanied by wind, and not followed by a thaw for many weeks, reduces the available food supply to a minimum, and drives the Grouse to travel far and wide over cultivated lands, into gardens, town outskirts, and even to the seashore for a scanty living. It is recognised that one of the best ways to help Grouse under such circumstances is to lay bare patches of heather by breaking through any hard crust that may have formed on the surface of the snow. This may be done either by rakes or harrows, and the spots chosen should be those where there is known to be the best supply of good feeding heather. As a rule there is sufficient wind with the snowfall to ensure that large tracts of ground remain uncovered on exposed ridges, and on the weather side of hill faces. When this is so, the Grouse collect on them ; but as these exposed tracts are always on the weather side, and almost always on the shoulder of a hill, it is usually the worst heather which is exposed ; the lee side is probably buried deep in snow. Attention has already been drawn to the benefit derived from sheep and deer in time of snow, owing to the surface of the snow being broken by their tracks. But although the ' " Annals of Scottish Natural History," vol. ii. p. 27. * Vide chap. xiii. pp. 370 et seq. 144 THE GROUSE IN HEALTH AND IN DISEASE heather may be exposed, and even though oats and corn may have been put down in abundance for the birds, the most important step has often not been taken to relieve the necessi- ties of starving Grouse. They must have grit, for without grit it is almost useless to put down corn. This was realised and put into practice in the snowstorm of 1881, but only by very few. Corn was put down here and there for the ravenous birds, and though some of it was eaten it was evidently not what they were most eager to obtain. On one moor, at any rate, men were sent out with shovels, not merely to expose the heather, but to open up the " scrapes " along the road sides all over the moor, and thus to expose fresh grit. Every day new grit was laid open and rotten quartz and sandy rock were broken out, and each day a fresh supply was needed. Grit, therefore, was what the birds v/ere really starving for, and it was the want of it that rendered them incapable of dealing with hard corn or winter heather. With good quartz grit they can deal with almost anything, even the very woody heather that appears above the snow ; without grit they will starve. Any one may assure himself of this by examining the winter crop-contents of the white-winged Willow Grouse or " Rype " of Scandinavia — ^the bird which decorates our poultry shops as " Ptarmigan " in winter. It is quite wonderful to see how excellent is the condition of these birds, living as they do on hard wooden alder twigs and buds, woody dwarf willow twigs and old rank heather. Their crop contents are extraordinarily hard and uninviting in appearance, and yet with good quartz grit everything is ground up and utilised. Another cause of death to Grouse is the ravages of birds and beasts of prey. This subject is dealt with elsewhere.^ Deaths also occur amongst Red Grouse owing to the anta- gonism which exists between the male birds of Blackgame and Capercailzie, and those of the Red Grouse. The two former have been blamed for the disappearance of Grouse from certain parts of the country. John Colquhoun, speaking of the decrease ^ Vide chap. xiv. pp. 405 et seq. CAUSES OF MORTALITY IN THE RED GROUSE 145 of Grouse in some districts says : " This may in part be attributed to the advance of cultivation ; but I cannot help thinking the Blackgame have a good share in driving off the Grouse, as I know of one instance where the former were killed off, and the latter again returned to their old haunts. I believe it is also more than suspected that the Capercailzie, wherever they are introduced, have a great inclination to dispossess both." 1 Com feeding is a habit which has become general among Corn feed- Grouse and Blackgame wherever the lie of the land permits, "'^' or the condition of a moor facilitates it. It is often mentioned as an accompaniment, or a cause, or a forerunner, or a consequence, of " Grouse Disease." The opinion of game- keepers on the subject is about equally divided ; some say that it does the birds more good than harm, and others say exactly the reverse. Occasionally yet another suggestion is made which appears on the whole to meet a certain proportion of cases, namely, that in certain districts the weaklings alone are to be found upon the stooks and stubbles, or, in other words, that corn feeding is a consequence of sickness, not a cause. Generally speaking, in districts where large packs habitually come upon the stubbles, it is probably because they have in- sufficient food upon the moors. Grouse when feeding on the stooks are generally not only healthy but wild, until they have filled themselves with com, when their habitual wariness often seems to leave them. This has long been recognised, and in Adam's " Reminiscences," for example, we find the state- ment that " Grouse, when they get on the plough are sometimes very stupid." ^ A case in point occurs in the extraordinary series of deaths to Blackgame caused by collision, which has been described above.^ Corn feeding is customary with healthy Grouse on some moors much more than on others ; but the evidence seems to show that when sick birds appear on the cornfields they are ' John Colquhoun, "Moor and Looh," p. 202, note. 2 Adam, " Reminisoenoes," p. 25, " Firfe pp. 119 etseq. K 146 THE GROUSE IN HEALTH AND IN DISEASE there because they are sick — not that they become sick because they have been upon the corn. St John notes that on August 12th, 1847, during a severe epidemic of disease in Morayshire, Grouse were feeding in numbers on unfilled green oats in the small fields near the moor. This, he says, he had never seen before, though he was accustomed to see Grouse flocking to the stubbles in the autumn.^ Sickly birds found feeding on the stooks were forwarded for examination in 1908, birds seriously diseased with Cobbold's Strongylosis, wasted piners that could hardly fly. These were probably sick birds that had been crowded out from the good feed on the moor by the healthier birds which live there in packs, the latter only occasionally make a raid upon the corn. The following extracts support the opinion that over-much corn-feeding is a precursor of disease : — Macdonald quotes as follows from a pamphlet written by Mr William Colquhoun of Ross-shire in 1858 :— " The Grouse have fed a great deal on the stooks during the disease (1854- 1856) ; and on the stubbles after the corn was stacked ; and also in spring on the sown corn. This year (1858) the Grouse did not come to the corn as in former years." (The disease had then quite disappeared.)^ Again Colquhoun says that Grouse thrive in confinement when fed on corn ; but allows that their greed for corn increases in disease years. He thinks that possibly they are upset by eating damaged and unwholesome heather, and are driven to stook and stubble for a sufficiency of food.* Speedy, too, writes as follows : — "An excessive consumption of corn by the Grouse species, particularly in wet seasons when the harvests are late, has been assigned as a cause of the ' Grouse Disease.' " * But he goes 1 Charles St John, " Natural History and Sport in Moray," p. 202. Edinbureh : David Douglas, 1882. 2 Macdonald, "Grouse Disease," p. 123. William Colquhoun, "Remarks on the Decrease of Grouse and the Grouse Disease," p. 29. Edinburgh : Edmonstou and Douglas, 1858. * Colquhoun's Pamphlet, p. 30. * Speedy, ' ' Sport in the Highlands and Lowlands of Scotland,'' p. 200. CAUSES OF MORTALITY IN THE RED GROUSE 147 on to say that hand-reared Grouse can live for several years in perfect health without seeing anything but corn ; and that whereas on the Dalnaspidal and Rannoch moors the birds were too far from cultivation ever to see corn, yet they suffered badly from disease in 1873. As with theories based on the belief that Grouse feed on frost-bitten heather, so with those that are based on their feeding upon corn, post-mortem examinations produce little evidence to show that they suffer any serious harm from the latter food, or that they ever under any circumstances fill their crops with the former. Turning now to the dangers and risks attendant upon the Eisks of natural processes of reproduction and moulting, we find jf^ that the exigencies of courtship, mating, and moulting in processes. the male, of moulting, the laying of eggs, and the hatching out and rearing of a brood of chicks in the female, constitute the sequence of a taxation which bears heavily upon the Grouse. It is worth while to look at these in detail to see how far each may fairly be burdened with responsibility. If an inquiry is made into the cock bird's life he will be found engaged in constant vigilance and warfare from the time of pairing, generally about the end of February or March, onwards for a month or two at least. The battles are more bloody and more disastrous to the weaklings than is generally supposed, and many of the half-starved and parasite-infected cocks, the so-called cases of " disease " found dead along the burns, have really been killed in fighting. It is a fact, testified by more than one reliable gamekeeper, that two or more healthy cocks will sometimes set upon and kill a weakling before they settle their own dispute ; and of the urgency of their own dis- pute the following quotation by Macpherson in the Fur and Feather Series affords a good example. He quotes a Perthshire keeper, who " saw two male Grouse engaged in combat, so completely blinded by fury were the birds that they dashed against the wall of a stone building, one of them killing himself 148 THE GROUSE IN HEALTH AND IN DISEASE with the impetuosity of his flight " ^ In the same work Mr Stuart- Wortley writes : "In the pairing season the old warriors come down from the heights, fight with and vanquish the younger ones, and absorb the young hens." ^ Such efforts combine to bring to an end a very large proportion of cock birds which are more or less exhausted after the winter by poor feeding and the loss of strength due to the presence of intestinal parasites. Then follows the moult, an exhausting process under the best conditions, and one for which nature generally makes provision by laying in a stock of subcutaneous fat. All this is consumed during the growth of the new feathers. But in the case of an ill-conditioned Grouse the moult commences with an insuflicient supply of fat from which to draw for the growth of new feathers. The result may be a complete failure to rise to the occasion ; or, if the failure be only partial, the old feathers, but only to some extent, are retained, and the new feathers will come slowly, poorly, and sparsely. Bare legs and a poor-looking mixture of old and faded feathers, with a more richly coloured new one here and there, produce a seedy, chequered-looking bird, and to this must be added an air of exhaustion and malaise. Occasionally in the male the summer change of plumage is not completed even by autumn, and feathers of three different plumages may then be found on a single individual. But as the season advances, and good food becomes more abundant, by degrees the moult is completed in a more or less satisfactory manner. The chief troubles are then over for the cock, and he gradually improves in condition, and is prepared to meet the ensuing winter. The lot of the hen is certainly less enviable than that of her mate. She also may have struggled through the winter, and while the cocks fight over her is quickly putting on fat for an early moult. She makes an almost complete change of plumage before laying her eggs in April ; and in this she must consume ' Macpherson, Fur and Feather Series, "The Grouse," p. 32. 2 Ibid., p. 147. CAUSES OF MORTALITY IN THE RED GROUSE 149 a portion of her strength. She recuperates in sitting, but feeds only scantily the while. Then her troubles begin to be more pressing, especially if by any mishap she loses her eggs and has to lay and sit a second time. If, however, by the end of June, she hatches off, she must still be constantly on the watch for danger to her chicks. In July she has to moult again. Little wonder that by August she is sometimes reduced to the con- dition of a " piner," or that, when the shooting season comes, she is discarded from the day's bag, to be submitted for ex- amination under the suspicion of " disease." It is the same story precisely as in the case of birds handi- capped for life through having been hatched late in a second brood. In the one case the birds are full grown and healthy to begin with, but have been unable to stand the strain of breeding and moulting. In the other case they have never had a chance to become full grown. In either case the course of natural taxation is the same, the parasitic infestment is the same, and the final result to the bird is the same. The only thing which differs is the primary cause of weakness, and this may be one, or several, of a very considerable number of causes that lie in wait for the life of the Red Grouse on every moor. Of accidents which may happen in the process of laying, there is one which is well known in captive birds, but is rare in nature, namely, a shortage of lime rendering the eggs deficient in shell. Soft-shelled eggs not only fail to stimulate the muscles of the oviduct, but give them no purchase upon which to act. The consequence is that the egg is not expelled, but is broken in the duct, and is followed by other eggs until the bird dies either from exhaustion or from a rupture of the oviduct involving the peritoneum. Soft-shelled eggs in wild birds generally appear in a second clutch laid shortly after the loss of the first nestful. Gastro-uterine gestation must always be rare, but one well- marked case in a Grouse was sent up for examination. The egg, when shed by the ovary, failed to enter the open upper end of the Fallopian tube, and so passed into the body cavity. By causing irritation there it became adherent to the peritoneal 150 THE GROUSE IN HEALTH AND IN DISEASE covering of three portions of the gut. The adhesions formed a firm support, and presumably the egg was for a short time carried safely. Eventually, however, it was broken in the peritoneal cavity, and the bird was shot, and owing to her unwillingness to take flight was forwarded as a case of suspected disease. Diseases of Disease of the skin is a very rare thing in wild Grouse, and the skin. ,» ,... ■, ■, i • generally results from the irritation produced by innumerable ectozoa or external parasites, such as ticks and lice. An example was furnished in an adult hen Grouse of 20 ounces, shot on August 12th, 1908, in Lanarkshire. The bird was very unprepossessing in appearance, as the feathers had failed to make their way through the skin of the head and neck especially, and to some extent all over the body. The skin was of a very deep yellow colour, and there were sebaceous cysts of varying sizes scattered all over the bird, and so thick on the head and neck that hardly a feather appeared. The gamekeeper's view was that it looked " like a hen that bad sat herself out on frosted eggs." There was no other abnor- mality discovered except the large size of the spleen which measured 20 mm. in length and 11 mm. in thickness. Another case which resembled the last occurred in a Grouse where Ixodes and Goniodes had again produced a great number of scabs and sores and warty excrescences all over the face and head, and especially in the neighbourhood of the ears and eyes. CHAPTER V " GROUSE DISEASE " History of " Grouse Disease " with an account of the work of the " Grouse Disease " Inquiry, in respect of previous work done by Professor Klein, Dr Cobbold, and others. " Geouse Disease " in its epidemic ^ form has become a serious matter only since the Grouse has come to be of import- ance in the economic management of estates in England and Scotland. Careful protection, improved conditions of food caused by heather-burning and drainage, and the removal, as far as practicable, of all animals that seriously threaten the lives of the birds, are some of the artificial means by which moors have become more heavily stocked with Red Grouse than was the case under more natural conditions. To this heavy stocking, combined sometimes with unfavourable natural conditions, but oftener with injudicious management, have been attributed the outbreaks of epidemic disease which have periodically visited the majority of Grouse moors. In other words " Grouse Disease " has always been considered to be intensified by artificial conditions. It is doubtful whether this view is correct. As early as the end of the eighteenth century we have records of serious mortality amongst the Grouse in certain districts, and "Grouse Disease" undoubtedly occurred in the earlier part of the last century, long before the artificial conditions had become established. Amongst the earliest recorded outbreaks of disease about 1 The familiar word "epidemic" is used throughout these volumes to signify out- breaks of specific diseases among Grouse in place of the more correct term " epizootic." 151 152 THE GROUSE IN HEALTH AND IN DISEASE the beginning of last century, Macdonald, in " Grouse Disease," says: "It is now (1883) eighty years since the alarm of 'Grouse Disease' was sounded in this country."' Speedy says : " The first time ' Grouse Disease ' attracted special attention was in 1838. Prior to that date it was not unknown in Scotland; but it had not assumed the proportions of a malignant epidemic. Even in 1838 and for several years afterwards, it was much milder in its results than it has latterly become. In 1867 it seems to have developed a most destructive form, attracting very general attention. Prior to that it was comparatively local, decimating the birds in certain districts, and leaving other districts untouched." ^ Howard Saunders says : "As long ago as 1815 a severe outbreak in the Reay country, Sutherland, was on record." ^ Mr Woodruffe Peacock in a pamphlet on " Grouse Disease " writes : " Old Moor Keepers have told me that their elders knew it as a slight and local trouble quite 50 years before 1847," i.e., in 1797.* And finally, in the MS. Records of Bolton Abbey, it is specifically mentioned as a " fatal disorder " in 1882 ; though as early as 1809 and 1811 there are records of "no shooting " — accountable in all probability to disease. It is therefore probably not correct to say that the first predisposing cause of " Grouse Disease " was protection leading to overstocking. The question is really of academic interest, since the artificial conditions are now firmly established. It might be profitable to consider the other theories which have been put forward as to the predisposing causes of disease. Such theories are numerous, and every one of them has at one time or another been promoted to the rank of " the real cause," the acting and primary cause, that is to say, of so-called " Grouse Disease." The subject has long held the attention of many ob- servers. Macdonald, Macpherson, Stuart - Wortley, Adams, ' Macdonald, "Grouse Disease," p. 112. ^ " Sport in the Highlands and Lowlands of Scotland," p. 184. ' " Zoologist," 1887, p. 302. ■* Rev. E. A. "Woodruffe Peacock, "Grouse Disease," p. 12. "GROUSE DISEASE" 153 Speedy, Teasdale-Buckell, and a host of other naturalists and sportsmen have supplied a large collection of interesting facts and observations, and an almost equal number of hypotheses and theories to accotmt for them, while Cobbold, Klein^ Farquharson, Colquhoun, Andrew Wilson, and Young have all contributed towards an understanding of the pathology of "Grouse Disease." It is proposed first to discuss the con- clusions at which various writers have arrived, and as the work of Cobbold and Klein stands out pre - eminently the simplest course will be to take their conclusions first. Dr Cobbold's view, was that " Grouse Disease " was entirely Dr Cob- due to a threadworm known by the scientific name of Tricho- elusions!'^ strongylus pergradlis found in the intestines of the bird. In his opinion "the irritation, probable distress and subsequent emaciation of the birds are readily explained by the presence of hundreds and thousands of strongyles ; and the mere circumstance that these parasites are very small, is quite sufficient to account for the fact that investigators have hitherto overlooked them." ^ He considered that the difference observed in the intensity of the disease during various epidemics might be partly accounted for by the presence of tapeworms and threadworms in varying proportions in the same Grouse, but that the strongyles were " sufficient by themselves to cause the death of the host " without the " assistance of a second kind of parasite." ^ He also thought that the intensity of the attack might vary with the strength of the individual victim. " A strong bird," he says, " will overcome or resist the irritation set up by the presence of hundreds of entozoa ; while a feeble bird, or one attacked before it is perfectly grown, will more or less rapidly succumb to the invasion. Professor Klein came to the conclusion that there was a Professor disease amongst Grouse which took the form of an acute ^isions°°'^ infectious pneumonia, and was characterised by the presence 1 T. Spencer Cobbold, M.D., P.L.S., F.R.S., "The Grouse Disease," p. 15. London : The Field Office, 1873. 2 Bid., pp. 24, 25. 154 THE GROUSE IN HEALTH AND IN DISEASE in the lung of a specific bacillus of the B. coli group. The disease had, he believed, two classes of victims, one which died rapidly in plump condition and fine plumage, and another which died slowly with emaciation. He puts on one side the whole question of parasitic intestinal worms as having no particular connexion with this epidemic pneumonia, and no casual connexion with the mortality. Cobbold differed from Klein in one important respect, viz. : — that he distinctly indicates that he did not observe any example of a Grouse dying in good condition and without loss of flesh. Neither Klein nor Cobbold suggest that they had any suspicion that they were dealing with two distinct diseases. Taking all these facts and opinions into consideration, the Committee at an early period adopted the provisional view that Klein and Cobbold had before them Grouse dead from two distinct diseases — (1) plump and well-conditioned birds which had died of an acute infectious pneumonia, i.e., the acute form of Klein's " Grouse Disease " ; and (2) emaciated piners which had died of the results of extreme parasitism, i.e., of Cobbold's Strongylosis. The view that two distinct forms of disease had in the past been confused under one term was supported by the literature on the subject, for all previous writers on Grouse and " Grouse Disease " had referred to a difference in character to be noticed between the disease outbreak of one year and that of another and between the appearance of the victims at one stage and another of the same epidemic. The following abstracts serve to illustrate the point : — William Houstoun of Kintradwell, Brora, says : "At that time it took the tapeworm type, but, when the disease next appeared, it had a different form, and I fear we are as far as ever from a solution of the cause." These later cases were presumably cases of Cobbold's Strongylosis, for the writer proceeds to describe that the intestines were distended " with a yellow feculent matter " "GROUSE DISEASE" 155 suggesting the appearance characterising the caeca in that disease, and the victims were all piners. Again, Macdonald described the earlier stages of the epi- demic as being much more virulent, the birds being found dead and dying in numbers by the water-courses, " which latterly was not the case." The plumage in the earlier attacks looked different, the feathers were dirty and draggled — an appearance which was " latterly not seen in diseased birds." ^ And again, quoting from " Land and Water " (1867), he says that " one striking difference between the disease of 1867 and that of former years was that the dead birds . . . picked up this season were so plump and in such excellent plumage that they had the appearance of healthy birds ; whereas in former years the diseased birds were most characterised by disordered plumage and attenuated bodies." ^ In another place he writes : " We have ourselves frequently picked up dead Grouse perfectly plump, and in excellent plumage one season, and in the next season found diseased birds with attenuated bodies and dull disordered plumage." ^ From this the Committee surmised that the disease which occurred in 1867 was Klein's pneumonia ; while in the previous records the birds had been victims of Cobbold's Strongylosis. This provisional view was again borne out by a letter written by Mr Macdonald to the Times, May 12th, 1873, which ran thus : "It seems that disease of an exceedingly virulent kind prevails in all parts of the Highlands, and in a form hitherto unknown. ... In 1847, 1856, and 1865 the infected Grouse exhibited a ' dull disordered plumage and attenuated bodies.' ... In June 1867 they showed good plumage, a healthy appearance, and were perfectly plump, although the liver was soft and discoloured. This year (1873) they are beautiful in plumage, but wasted to skeletons . . . and with full crops." * This occurred evidently in later autumn, since mention is made of the large quantities of berries in their crops. ' Macdonald, " Grouse Disease,'' p. 127. ^ Ibid., p. 155. 3 Ibid., p. 131. * Ibid., p. 155. 156 THE GROUSE IN HEALTH AND IN DISEASE All these quotations seem to point to the fact that in 1856 and 1865 there was an excessive mortality from Cobbold's Strongylosis ; whereas in 1867 there was an epidemic of Klein's acute infectious pneumonia. Again, in Adam's " Reminiscences " we find : " Disease in this attack (Dalnawillan, 1882) was very different in its aspects from former attacks. It came on very suddenly, sharp and decisive." ^ The distinction is markedly contrasted by Adams in his book, and the incidence in each case is well described. Tom Speedy in " Sport in the Highlands and Lowlands of Scotland " writes : " The epidemic assumed two different forms. In some cases the birds were draggled, wasted, and emaciated, bare about the legs, and indicating ... a long continued or fatal disease. At a more advanced period of the season they were found dead in beautiful plumage, with fine feathery legs ; and the red above their eyes unsullied and as bright as vermilion. In many cases they were seen the one day seemingly in perfect health, and the next day stiff and cold in excellent condition." ^ Enough has now been quoted to show that in the minds of many observers there has been for years the suspicion that the differences observed were not merely two phases of one form of sickness, but two distinct diseases. And it was on this assump- tion that the Committee at first commenced their investigation. On following up this provisional hjrpothesis, however, it was found difficult to reconcile the opinions of former writers with the facts observed. One thing was quite certain, that whereas the Committee had seen during the first three years of the Inquiry extensive mortality amongst Grouse caused by some agent which acted slowly and produced " piners " only, they had not seen anything at all like an epidemic of acute or infectious pneumonia. It followed therefore that if the rapid death of birds in good con- dition was typical of Klein's disease no case of Klein's disease had yet been seen. ' Adam, " Remmiscences," p. 75. 2 Qp. cit., p. 185. "GROUSE DISEASE" 157 During the whole investigation the only form of disease observed among adult birds was a widespread mortality of " piners " owing to what appeared to be a form of starvation caused by an excessive number of the threadworm known as Trichostrongylus pegracilis in the caeca. This form of disease is quite comparable to the form of " Grouse Disease " described by Cobbold. The widespread idea that tapeworms are at the root of one Tapeworms form of trouble is perhaps natural, considering that it is common oaustTof ^ knowledge that in some animals they are the cause of serious disease. wasting. Moreover, the very first thing that appears when a Grouse is opened up, whether purposely or accidentally, is a mass of large white tapeworms. What could be more natural, since the bird is wasted to skin and bone, and tapeworms are found in large numbers, than to consider the one to be the cause of the other. But if only threadworms were as conspicuous as tapeworms, outnumbering them as they often do, to an almost incredible extent ; or if some distinction had been earlier recognised between the main gut of the Grouse and its caecal appendices, there would before now have been a strong following of Dr Cobbold, and the pining form of disease would be more readily associated with the presence of the smaller worm. All birds dying from Strongylosis must be " piners," because their death results mainly from an inability to absorb nourish- ment owing to the caecal lining or mucosa being damaged. The consequent emaciation is a sine qua non in the diagnosis. It is hardly necessary here to quote the accounts of dis- sections which have been recorded from time to time (many unfortunately in the most cursory manner), with a view to ascertaining what pathological lesions were found to account for death. The subject is fully discussed in the original Report of the Committee, and may be found at greater length in the published works of Dr Cobbold, Professor J. Young, John K. Lord, F. Buckland, Tom Speedy, Professor Klein, and Dr Andrew Wilson. 158 THE GROUSE IN HEALTH AND IN DISEASE Cause of Professor Klein's error. The foregoing resumi is necessary in order to show the position of the controversy when the Committee of Inquiry was beginning its work. It explains many of the unavoidable errors into which the Committee was led by the inaccuracy of much that had been published on the subject. Even Professor Klein's work, accurate and painstaking as it was, and clear as were his published descriptions of whatever he himself saw, was misinterpreted by him for the sole reason that bacteriology (a science of which he was one of the most honoured founders) was still in its infancy. His deductions as to the disease being an acute infectious pneumonia due to a specific bacillus have now been shown to be founded upon a misconception; but, in the days when he was working at the subject, no one could have arrived at other conclusions than those to which he himself came. It is due to so great and careful a worker to say that at that time he was years ahead of any other bacteriologist in this country. That he should since have been found to be in error merely shows how dependent is science upon the methods avail- able at the moment, and how impossible it is for any one at any time to be certain that even the most probable explanation of observed facts is the right one. The doubts of the Committee were confirmed when their bacteriologist, Dr Seligmann, found that the bacillus which Professor Klein considered to be the specific cause of Grouse pneumonia was in fact only to be discovered in the lungs some twelve to twenty-four hours after death. It became gradually clear that not only the grosser appearances in the lung which Klein considered to be due to pneumonic con- gestion, but the microscopic appearances of the lung-tissue in section, as well as the colonies of bacilli which he described and figured in the Ixmg, were in fact only to be found some hours or days after the death of the bird. They were undoubtedly due to a post-mortem migration into, and colonisation of, the tissues in question by numbers of Bacillus coli which had escaped from their proper sphere in "GROUSE DISEASE" 159 the intestine at the moment when the normal defence had broken down. It gradually began to dawn upon the Committee that the appearances in the lung upon which Klein had relied in making a diagnosis of acute infectious pneumonia differed in no way from the appearances which had been observed by the Com- mittee in the lungs of hundreds of birds found dead from all causes, including Cobbold's Strongylosis, general Helminthiasis, accidents, or even shot wounds. This discovery undermined the faith which the Committee were prepared to place in the existence of Klein's acute infectious pneumonia, and it soon became evident that in birds obviously dying of " Grouse Disease," there was no dangerous ante-mortem infection of the lung or other tissues with the bacillus in question, and no recognisable lesion in any organ of the bird except in parts of the intestine. All the appearances which were previously attributed to Klein's pneumonic disease, were now found to be due to post-mortem, change alike evident in diseased and in perfectly healthy normal birds. The point was further tested by taking a number of healthy pigeons, and killing the whole of them at the same time with chloroform. The birds were numbered and opened on consecu- tive days and the change in the appearance of the viscera was noted. It was evident that in every case where there had been extravasation of blood or serous fluid owing to rough handling, or damage by the knife in dissecting the pigeon, the tissues of the lung became black, and took upon themselves precisely the same appearance that is seen in a Grouse found dead upon the moor, or examined some days after being shot. The appearance of pneumonia was evidently due to a soak- ing of the lung-tissue in decomposing blood and serum, and the post - mortem colonisation of the tissues by Bacillus coli. Once this fact became clear, the Committee was no longer burdened with the task of recognising and investigating the type of " Grouse Disease " described by Professor Klein, for it 160 THE GROUSE IN HEALTH AND IN DISEASE now became impossible to accept his explanation of the disease. It then became necessary to set on foot more detailed investiga- tions to determine the following points : — 1. To prove that the amended view of Klein's work was the right one, and that the " Grouse Disease " which he saw and described as a form of infectious pneumonia was in reality not different from the " Grouse Disease " which the Committee were seeing constantly, and were describing as Cobbold's Strongylosis. 2. To make a complete investigation of the life history of the Trichostrongylus pergracilis or the Strongyle of Cobbold, with a view to ascertaining its mode of infect- ing Grouse, its action in the caecum of the Grouse, its method of reproduction, its dissemination, and the con- ditions which enable it to hatch from the egg, to pass through the stages of development, to survive on a Grouse Moor, and to enter a bird at a stage when to be swallowed means completing the cycle of parasitic life, instead of being merely digested. The life history of this threadworm was obviously required in its smallest details, in order that Strongylosis might be understood. 3. To discover whether this or any other form of " Grouse Disease " was caused by bacterial infection or not. For convenience this may be called the bacterial theory. 4. To investigate the blood of the Grouse in health and in sick- ness, and especially to try and discover whether death was caused by toxins introduced by parasites in the intestine. This might be known as the "blood-poisoning" theory. 5. To make certain that " Grouse Disease " did not result from the presence in the intestines, or in the blood, of any protozoal parasite. This might be called the protozoal theory, 6. To complete the investigation of the Grouse parasites, ectozoa as well as entozoa, with a view to determining whether " Grouse Disease " could be considered attribut- able to some of them, or even to one of them. "GROUSE DISEASE" 161 The last four years of the Committee's work were devoted mainly to the study of the foregoing questions. The detailed results of their investigations are given at length in the original Report, and, though their conclusions may be subject to modifica- tions in detail, it may be claimed that these have gone far to elucidate the main points involved. These conclusions may be summarised as follows : — 1. So far as the observations of the Committee were con- cerned Klein's infectious pneumonia is not a separate and distinct disease from Cobbold's Strongylosis. In fact, to be more precise, Klein's disease was never observed, 2. The life history of the threadworm Trichostrongylus pergracilis was satisfactorily traced.^ 3. The investigations failed to establish any connexion between " Grouse Disease " and bacterial infection due to the presence of parasites or any other cause.^ It was not f oimd that the bacilli which find their way into the organs did much harm. Some harm no doubt they do ; but how much cannot be accurately ascertained. 4. It was not found that mortality was due to toxaemia caused by parasites in the intestine. 5. It was not found that extreme mortality among adult Grouse was caused by the presence of parasitic protozoa in the intestine.^ It may, however, be noted that in the course of investigating this point the Committee dis- covered a hitherto unobserved disease among immature Grouse, which was caused by the presence in large numbers of the protozoal parasite Eimeria {Coccidium) avium in the intestine.* 6. The ectozoa and entozoa of Grouse were carefully investi- gated, but no extensive mortality could be traced to any of them with the exception of the Trichostrongylus pergracilis of Cobbold, and to some small extent to the smaller tapeworm Hymenolepis microps.^ * See chap. viii. pp. 219 el seq. ^ See chap. viii. pp. 215 et seq. ' See chap. ix. p. 244. ■* Ibid. pp. 214 et seq. ' See chap. vii. p. 198. L 162 THE GROUSE IN HEALTH AND IN DISEASE The question has frequently been asked whether there is an epidemic form of " Grouse Disease " which in spite of minute inquiry and search has eluded the vigilance of the Inquiry during the last six years, and whether the Committee never came across the genuine epizootic " Grouse Disease " at all. Apart from the question of whether Klein's pneumonia has any existence in reality, all the outbreaks of disease amongst Grouse which have come under the observation of the Com- mittee can be ascribed either to Strongylosis or to Coccidiosis, the only two diseases which are now recognised as causing widespread mortality amongst Grouse. And the principal sign of both these forms of disease is loss of weight. Yet one of the most persistently quoted observations, which some sportsmen and gamekeepers still maintain to be true in fact, is that in some epidemics there is a certain proportion of birds which succumb to so acute and virulent a form of " Grouse Disease " that they die before any loss of flesh or weight can have time to show itself, and before any change in the appearance of the feathers becomes manifest. This view is founded not on actual measurement of weight, but on the bird's general appearance of good feather and normal weight, as estimated by the observer who takes the bird in his hand when it is found dead on the moor. In most alleged outbreaks of " Grouse Disease " the birds have been collected and burned, or buried by the score in a moss-hag or under a rock. They were never weighed, and never carefully examined. Yet without careful weighing and examination it is impossible to come to any reasonable con- clusion as to their condition or the cause of their death. The Committee's field-observer has himself been present on several occasions when such birds have been picked up and passed from one to another of the keepers and the gillies ; full-feathered, richly-coloured hens, perhaps found almost warm but dead upon their nests. And these birds have been weighed in the hands and their weight guessed as fully normal, notwith- standing the condition of the breast, yet the spring balance "GROUSE DISEASE" 163 has invariably proved appearances deceptive, except in the cases where accident has been the cause of death. In the case of a hen whose feathers have been recently donned for nesting, a most misleading impression of good condition is given even in a wasted bird. In the cocks it is different, for the feathers have not been changed for the nesting season, and the plumage is often worn and faded in comparison with the new nesting plumage of the hen.^ It is often hard to believe that a hen Grouse which has died in full nesting plumage, however thin and poor, is not actually heavier than the dingy cock bird of the same month. And if no rain has fallen on the hen since her death the com- parison between her and the cocks which are found in all stages of disease, decayed, weathered and bleached, is even more misleading. The point has now been too often tested to allow of doubt. No bird dies of Strongylosis without loss of weight. That some birds waste more and some less before succumbing to the disease is certainly true, the difference in this respect depends mainly upon the season, but sex and individual strength also make a difference.^ On this point the Committee can speak with entire con- fidence. During the whole period of the Inquiry, from 1904 to 1910, there has not been a single outbreak of " Grouse Disease " in which the birds died without loss of weight. While, therefore, it is possible that a virulent and sudden form of disease does, in fact, sometimes occur, it is also possible that the belief in it is entirely without justification, and is the result of inadequate method and inaccurate observation. ' Vide chap. ii. p. 42. ^ Vide ohap. i. p. 33. CHAPTER VI ANATOMY AND PHYSIOLOGY OF THE RED GROUSE As a preliminary to the proper understanding of the method of infection in the forms of " Grouse Disease " known respectively as Strongylosis and Coccidiosis certain facts concerning the functional activities of the different parts of the Grouse's alimentary canal should be explained. By the alimentary canal is meant the whole tract of the digestive apparatus from the mouth to the anus or vent ; and the following is briefly a history of the experiences undergone by a morsel of food after it has been swallowed by a healthy bird. In the case of the Grouse it is reasonable to take a small sprig of heather, Calluna vulgaris, with a somewhat woody stalk and a number of very small greenish or brownish green leaves, and perhaps a few small pink flowers or shrivelled flower heads containing a considerable number of very small seeds. Other foods, of course, are frequently eaten, but all the vegetable stuffs may be considered as partly composed of soft, alterable, and digestible material, such as starch, protoplasm, chlorophyll, and sap solutions, and partly of indigestible woody fibres. The animal foods, whether they consist of insect or mollusc, worm, crustacean or spider, can also be considered as composed partly of soft, digestible material, and partly of indigestible matter, such as chitin. And further, the function of the grit must be considered, since it is as essential to the well-being of a herbivorous or graminivorous bird as are teeth to the higher mammals. The sprig of heather is partly plucked, partly cut from the 164 ANATOMY AND PHYSIOLOGY OF RED GROUSE 165 growing plant by the beak of the bird In captivity it is found necessary to fix the bunches of heather either by tying them to the wire run or by placing a heavy weight upon the roots ; should this precaution be neglected the bird, having no notion whatever of using its feet to steady anything, drags the loose heather all over the ground in unsuccessful efforts to pluck off the tips. There is sometimes to be seen quite a free flow of watery saliva from the beak of a feeding bird, and in the mouth of birds killed there is always a certain amount of saliva. This saliva serves to coat the rough hairy heather tip with mucus, and thus to facilitate its passage down the oesophagus or gullet to the crop (PI. xvr.). The food is, of course, swallowed whole but in very small pieces, and there is no mastication. The length of the oesophagus (PI. xvi.) from the pharynx to the proventriculus or first part of the stomach^ is 5| inches, when the neck is normally outstretched ; but before passing down the whole length of this tube the food finds its way into a thin-walled sac or diverticulum of the oesophagus, at a point 3 inches from its entrance at the pharynx, and commonly called the " crop " (PI. xvi.). Here the food collects, and remains for a longer or a shorter period according to the rate at which the gizzard can dispose of it. The lower portion of the oesophagus measures 2 inches in length, and the opening of the crop occupies over half an inch of its length. The proventriculus (PI. xvi.) forming the thick -walled glandular part of the stomach has a cavity of very small dimensions, and a length of | inch. It is lined with large mucous glands having prominent mouths. These secrete a thick, tenacious, opaque white fluid, wherewith the morsels of food on their passage from the crop to the gizzard are coated. In this respect there is a very great difference between the condition of the food as it leaves the crop, and its condition in the gizzard. In the crop the food is almost invariably dry, ^ The stomach of a bird is divided into two portions, the proventriculus and the gizzard. 166 THE GROUSE IN HEALTH AND IN DISEASE almost exactly as it is plucked from the living plant, and it is found thus in masses fresh and green, or greenish brown, with no appreciable admixture either of mucus or of water. Probably when there is food in the crop, no water is drunk, for there is never any wetness either in the crop, proventriculus or gizzard, all of which are occupied in turn by the morsels of food in process of digestion. From the proventriculus the bits of food, coated now with a tenacious and slightly acid mucus, are passed into the muscular gizzard (PL xvi.), a familiar object in the anatomy of the common fowl, and an organ of very similar shape and of equal muscularity in the Grouse. Its walls are very thick, and the muscles which compose them act from tendinous sheets, into which they are firmly fixed. The cavity of the gizzard is comparatively small and contains about a teaspoonful of small hard subangular or rounded grains of hard rock. The substance almost universally chosen as grit by the Red Grouse is quartz, and although on the moor, as in captivity, the bird will swallow any small portion of hard material which comes in its way, quartz is most suitable, not only for the Grouse but for every other graminivorous bird in health. The subject is more fully dealt with in chapter iii. The food having reached the gizzard with a free admix- ture of slightly acid mucus, is now thoroughly mixed up with the grits of quartz, and ground with their assistance to a pulp, the harder woody fibres soon showing up as whitish bits in a brownish, greenish, or reddish mess. This vegetable pottage has now to be separated from the quartz grits, and to be passed little by little into the duodenum. The separation is effected by the sphincter or ring-like muscle at the exit from the gizzard, and the digestible food, including our particle of heather, now sufficiently pulped, is separated as it leaves the gizzard from most of the harder and larger grits, and enters the duodenal loop of the small intestine. The duodenum (PI. xvi.), 6| inches in length, begins at the exit of the gizzard and is U-shaped. It consists of two TONGUi ANU6 E Wil^ion.Cambridae ANATOMY AND PHYSIOLOGY OF RED GROUSE 167 parallel " limbs " of about equal length. These two limbs are supported and held together by a mesentery which contains the pancreas (PI. xvi.), a pale pink, flattened glandular mass filling the space between the descending and ascending limbs. This gland pours its alkaline and digestive pancreatic juice and ferment into the upper end of the descending loop. The liver (PI. xvi.) also pours its alkaline, biliary secretion into the upper end of the descending loop, so that it is intimately mixed with the pulped food as it passes into the duodenum little by little. The shape of the loop assists this admixture, since it checks the immediate passage of the con- tents into the small intestine. Digestion is now ready to go on apace. The food, when being macerated and pulped in the gizzard, is distinctly acid ; but, when mixed with the alkaline pancreatic and hepatic secretions from the liver, becomes gradually neutralised until it is of the right reaction as well as at the right temperature for the action of the digestive ferments. In the duodenum the contents are normally almost fluid, when there are no tapeworms or threadworms present. The duodenum is, however, the common habitat of the tapeworm Hymenolepis microps,^ and of the threadworm Trichosoma longicolUs ; ^ and the former of these is frequently present in such large numbers as to appear like a soft, semi-solid, creamy mass completely filling the whole length of the duodenum. It is only when this worm is absent, as it generally is during the winter months, that one appreciates the fact that the duodenum seldom contains at any one moment more than a very small amount of solid food pulp mixed with the digestive fluids. The passage of the food through it is slow and gradual, and the admixture with the alkaline digestive juices is propor- tionately complete. Normally the outward appearance of this part of the intes- tine is a pale creamy white, and the mesenteric vessels which 1 Vide p. 197. ^ Vide p. 199. 168 THE GROUSE IN HEALTH AND IN DISEASE ramify over the peritoneal surface are almost invisible. The pancreas also should be pale creamy white or faintly pink. The alkaline mixture now passes from the duodenum into the convoluted upper portion of the small intestine (PI. xvi.). This extends from the lower end of the duodenum to the upper end of the rectum (PI. xvi.), where the two caeca enter it. The small intestine measures in all 35 inches, but there is a distinction to be made between the upper con- voluted portion and the lower straighter portion (PI. xvi.), for the convoluted portion is freely movable, whereas the straight portion is so intimately folded with the long csecal appendices, and so closely bound together with them in a common mesentery as to be very limited in its movement. The various parts of the lower intestine are shown laid out in the accompanying diagram (PI. xvi.). Returning, however, to the changes which are being ex- perienced by the particle of food in question, as it passes from the duodenum into the convoluted portion of the main gut, it is first noticed that the duodenal tapeworm, Hymenolepis microps, wholly disappears, and that its place is taken by the much larger and more conspicuous tapeworm, Davainea urogalli, often in such quantity that the outward appear- ance of the small intestine is altered to a swollen, bulky gut of a creamy white colour due to the enclosed mass of white tapeworms shining through its thin and distended walls. It has already been noticed that the neutral or faintly acid reaction of the contents of the duodenum has gradually changed to a more and more markedly alkaline reaction. Hymenolepis affects a neutral medium, and Davainea an alkaline medium. These changes in the character of the intestinal contents can, of course, be easily tested by the use of litmus papers ; but when a Grouse, which has been feeding upon ripe Blaeberries, Cranberries, or Crowberries with coloured juices, is examined, the contents of the alimentary canal of the bird itself are found to be coloured within from end to end, in such a way as to make ANATOMY AND PHYSIOLOGY OF RED GROUSE 169 litmus unnecessary. The juices of the berries are red, and stain the tissues red wherever the acidity is not overcome by alkaline digestive juices. But wherever there is a slight alkalinity in the juices there the tissues are stained bluish. In the convoluted intestine the food is in a somewhat fluid state ; and as the mere presence of convolutions in the intestine of any animal are evidence of the necessity for a retarded passage, the function of the convolutions in this case is obviously to hold the mixture for a sufficient length of time at a certain regular temperature to enable the active digestive ferments to complete their work upon the food-pulp. The heather fragments are thus altered into a solution of digestible food and indigestible refuse of woody fibre. The former is now ready for use by the tissues of the body as soon as it can be brought to them by the agency of the circulating lymph and blood. Certain harmful and poisonous products will also unavoidably appear in the Grouse's intestine as they do in the human intes- tine and in the intestine of every living animal from time to time, even in the ordinary course of digestion. These, as in the human body, having been absorbed with the soluble food supply into the blood are then eliminated, chiefly in their passage through the liver, before the mixture of good and evil products can be thrown upon the general circulation. The liver in man is the great eliminator of poisons produced in the intestine, and the liver in the Grouse almost certainly acts in a similar way. By the time the food reaches the lower and straighter portion of the small intestine it is seen that much of the fluid has dis- appeared, the contents are becoming more and more thickened, and are now converted into a semi - fluid paste intermixed with woody particles. By the time that the contents reach the junction of the small intestine with the rectum they have been still further prepared for separation. At this point the csecal appendices or caeca (PI. xvi.) open into the main gut. Each caecum measures from 30 to 36 inches in length. Their colour in health is a dull drab grey, while 170 THE GROUSE IN HEALTH AND IN DISEASE that of the small intestine is greenish. All that is soft of the food is now squeezed into the narrow openings of the caeca, while all that is hard, including the indigestible part of the heather fragment, the indigestible woody fibres, and the refuse of the cellular tissues, is compressed into a firm, dry mass, and passed straight into and along the rectum. The exact method of separation is due to the action of the sphincter muscles which regulate the opening and closing, not only of the two entrances to the csecal appendices, but also of the entrance to the upper end of the rectum. Each caecum at its junction with the main gut is guarded by a narrow tubular portion (PL xvi.) some 4 or 5 inches in length, which admits nothing to the caecum except the softer parts of the pulpy mixture. The pultaceous, creamy- brown pulp must be squeezed into these csecal back-waters by the pressure of the small intestine from above, while, at the same time, the rectum remains closed and refuses to admit anything at all. In this way all the nourishing contents of the main gut pass into the caecum, and are there absorbed into the blood and system generally of the Grouse, any portion still remaining undigested passes out again by the same orifice. Yet the caeca always appear to be filled to some extent by material from one end to the other. It is only after a prolonged starvation, say for twenty-four hours or more on a railway journey, that the caeca are found to be partly empty, and it is obvious from observation that the riddance begins by contraction of the blind end, and that it gradually works toward the open end. It would appear from this that there must be a pause in the entrance of material to the caeca while the waste matter is being evacuated. The muscles of the small intestine seem thus to act intermittently but without any long period of rest. The caecal muscles, on the other hand, must have long periods of rest when the caecum is full and actively absorbing, and then a period of activity to empty itself. But these periods of rest and activity must be of very different length. It is probable ANATOMY AND PHYSIOLOGY OF RED GROUSE 171 that after full feeding in the evening the Grouse jugs in the heather, and the process of digestion and the action of the intestine proceed until there is a large quantity of hard and soft food in the lower part of the small intestine ready for selective absorption and separation. This separation probably proceeds all night, the soft material constantly passing into the caeca, and the harder waste matter passing on as constantly into the rectum and out at the vent. Then, early in the morning the action is reversed, the passage of food down the main gut ceases because the supply from above has stopped during the night when, of course, nothing has been eaten. The useful part of the csecal contents has now been absorbed, and is circulating in the blood, and the caecum therefore contracts downward and expels all the waste matter that is in it. This is confirmed by what one sees upon the moor, by the absence of csecal excreta amongst the heap of formed droppings passed in the night, and by the appearance of caecal excreta either on the top of these heaps, or more frequently in their near neighbourhood or near the early morning drinking and feeding resorts. It has already been stated that the Grouse feeds more or less all day ; but, as a rule, the crop is found fullest in the evening. Probably digestion is sufficiently rapid during the day to deal with the food almost as fast as it is picked and swallowed. It may be that the caecum receives matter both by day and by night, and discharges its contents only in the early hours of the morning ; but these details are not easy to determine in the wild bird. It is easy to see how indispensable it is to the well-being of the Grouse that the caeca, whose combined length nearly equals that of the rest of the alimentary tract, and which are responsible for the absorption of most of its food, should be in good working order. It seems impossible to exaggerate their importance in the bird's economy, for if they are put out of action the bird may eat as much as ever and yet rapidly lose flesh by sheer starvation. One portion of the alimentary canal remains to be mentioned. 172 THE GROUSE IN HEALTH AND IN DISEASE namely, the rectum (PI. xvi.). This measures 4| to 5 inches from the point of entrance of the caecal appendices to the anus. The rectum appears to empty its contents almost immedi- ately after receiving anything from the main gut or the caeca. When examined by dissection it is generally empty ; but there is one marked exception to this statement. In the hen Grouse, during the laying of eggs and incubation, but especially during incubation, the want of exercise, and the necessity for keeping the nest clean, leads to an excessive accumulation of faeces, always of the harder, formed kind, in the lower part of the rectum. This accumulation of faeces results in an enlargement and distention of the lower part of the rectum and the cloaca, which recover themselves only after incubation and hatching are completed. The massed and bulky droppings of a sitting hen Grouse, or " docker " as she is called, afford useful information concerning the number of nests upon a moor. As these " docker's " droppings are only to be seen in the nesting season, it is perhaps not surprising that the keeper alone recognises what they mean. They are usually to be found along the side of burns and springs. Such places are used habitually by sitting hens when they leave their nests, perhaps once or twice a day, for food, grit, and water, and these droppings supply far more satisfactory evidence of the season's prospects than could be gained by disturbing the birds on their nests. This then is, as briefly as possible, the normal course of the digestion and absorption of food by the Red Grouse, and it remains now to speak of the more common variations and disturbances which affect this process and which upset the health of the bird. Many such variations have come to light during the past seven years in the course of dissecting something like a couple of thousand Grouse : of these some were healthy and some unhealthy ; but in this chapter no accoimt is given of damage ANATOMY AND PHYSIOLOGY OF RED GROUSE 173 resulting from shot wounds, collision with wire fences or similar accidents. This subject has already been dealt with.^ By far the more important pathological changes which are to be found in the Red Grouse are those which result from ex- cessive parasitism, and they are therefore discoverable as a rule in the intestines, and above all in the two blind caeca, which afford a habitat to thousands of the round-worm Tricho- strongylus pergracilis. The particular damage caused by this threadworm resulting in the fatal Grouse disorder which is now called Strongylosis, will be dealt with in chapter viii.^ It will best serve the purpose in view to take again the alimentary tract from end to end, and to mention the lesions to which the various parts are liable.^ It is a very rare thing to find any disturbance in the upper reaches of the alimentary canal. The mouth, the oesophagus, the crop, the proventriculus, and the gizzard as a rule carry no parasites, and are very seldom the seat of any pathological trouble. But it may happen that a bird gets hold of some irritant poison with its food, and this probably accounts for one or two otherwise unaccountable cases of inflammation of the crop walls, with engorgement and enlargement of all the vessels ramifying over it. In the duodenum it is comparatively common to find the lining intensely inflamed, showing a bright red surface to the naked eye, sometimes all over, and at other times in patches. This is apparently the result sometimes of the presence of the tapeworm Hymenolepis microps, in large numbers ; sometimes of the presence of the threadworm Trichosoma longicoUe. But although in many cases the lining is thus reddened and Hymenolepis and Trichosoma are abundant, it is also quite as frequently found that the worms are present without any reddening, and in some cases reddening is present without any sign of a worm. It is probable that in many of these cases where there is ' Fide chap. iy. pp. 119 et seq. " Vide chap. viii. p. 204. ' Vide Diagram, p. 165. 174 THE GROUSE IN HEALTH AND IN DISEASE inflammation of the duodenum and smaller intestine, Coccidia have been the cause and have been overlooked, and that the more obvious threadworms (Trichosoma) have really little or nothing to do with the engorgement. It may exonerate the tapeworms Hymenolepis and Davainea to some extent, that both may be present in masses without any accompanying inflammation, but the association of a large number of the threadworm Trichosoma in the duodenum with the symptoms referred to is too frequent to allow this nematode to escape blameless. Trichosoma is probably a harmful worm, but as it only occurs occasionally, the damage done by it is comparatively trifling. Typically the duodenum when badly infested by Hymeno- lepis looks bulky and translucent, swollen and soft, and is of a pinkish yellow colour, with thin walls. The upper end of the ascending limb is often deeply stained by contact with the liver. The fluid contents, always small in amount, are generally yellowish, and may be blood-stained if Hymenolepis and Trichosoma are present in excessive numbers. It is not a rare thing to find that in a sick bird the control of the lower sphincter of the gizzard is lost at the point of death or somewhat earlier, and that the grits have passed out of the organ in large quantities into the duodenum. Normally the grits are retained in the gizzard for a considerable time, certainly for months, if they are of any size. Much depends upon the nature of the food, and, as already explained, the presence of hard, woody seeds may lead to the loss of most of the gizzard grits, in which case they are passed with the dejecta.^ Passing now to a consideration of the small intestine, and its pathological manifestations, the first noticeable point is its external appearance when really full of the large tape- worm Davainea urogalli, as is so frequently the case ; the gut is distended, and appears fatty, thin-skinned, whitish - yellow in colour, and rather translucent. Within, there are 1 Fide p. 112. ANATOMY AND PHYSIOLOGY OF RED GROUSE 175 often great masses of Davainea, but no redness of the mucous membrane. The only pathological appearance which is commonly seen in the rectum of the Grouse is a reddening along the glandular ridges, due to villous engorgement. The cause of this villous engorgement is obscure. It does not appear to be dependent upon disease or sickness, though apparently sometimes it has some relation with an excessive number of tapeworms in the main gut. In the caeca of the Grouse lies the whole origin and cause of " Grouse Disease " in the adult bird. In these blind guts live Trichostrongylus per gracilis, and these, when present in enormous numbers, produce an excessive amount of irritation and congestion of the vessels, and so much disturbance of the proper functions of this portion of the gut that the contents, consisting of food, mucus, nematode worms, and nematode ova in a pasty and decomposing mess, not only become use- less as food, but may be a grave danger to the bird owing to the amount of toxins produced and absorbed into the circulation. With regard to other organs of the body of the Grouse there is more to be said of the lungs than of any other. On this subject the reader may be referred to chapter xii. of the Com- mittee's Report, where Dr Cobbett and Dr Graham Smith have described in detail the appearance of really fresh lungs, exposed in birds just dead, and their appearance after being more or less stained by post-mortem fluids and decomposing blood. It is unnecessary here to repeat the discussion upon the question of " Grouse Disease " and pneumonia. For this refer- ence must be made to chapter v., where reasons are given for the belief that Klein's explanation of " Grouse Disease " as an acute infectious pneumonia is not the correct one.^ The normal colour of quite fresh healthy lung is a very 1 Vide p. 159. 176 THE GROUSE IN HEALTH AND IN DISEASE clear pink, almost a whitish pink until the organ is cut into, when it is found to exude bright red blood, and the cut surface therefore inunediately becomes bright red. The appearance of fresh lung in bad cases of Strongylosis does not vary at all from the appearance of the lung in a healthy bird, and there is no sign of solidification or of the earlier stages of pneumonia, congestion, or infiltration in the lung as a symptom of the disease. Pneumonia proper must be an exceedingly rare disease in the Grouse, and probably ninety-nine out of every hundred diagnoses of it are the result of a failure to realise that post- mortem staining and infiltration give an appearance which may be mistaken for pneumonia. It is exceedingly difficult to find even a very small piece of this so-called pneumonic lung which will not float in water, and this is a fairly reliable rough-and- ready test for consolidation. With regard to the liver there is very little to be said. It is an organ which changes perhaps more rapidly post-mortem than any other, both in appearance and in consistence, and yet more has been deduced from its post-mortem appearance than from any of the more reliable indications of disease in Grouse. If the liver be examined fresh, even from a bad case of Stron- gylosis, it will be found to present a normally firm consistence and a healthy red colour. It is true that it may, and probably always will, partake of the general congestion which charac- terises Strongylosis. But this alters its normal appearance very little when it is fresh; it may be a darker red, and it may be more friable, but the change is hardly noticeable. The " black " and " tarry " livers may be ignored, unless they occur in birds that have only quite recently died, as being indications of no value from the diagnostic point of view. Discoloration even in a fairly fresh liver will often be found upon section to be very superficial and to be creeping towards the centre from the surface of the interior. Hence the first portion to show the change right through is always the edge of the anterior lobes. ANATOMY AND PHYSIOLOGY OF RED GROUSE 177 The spleen of the Grouse varies very much in size, and this fact appears to have some connexion with Strongylosis. It is comparatively large in young and healthy birds, and is large, as a rule, and of a fresh, red colour in healthy adult birds ; but in cases of Strongylosis it becomes very small and very dark, an appearance which is noticeable in fresh, dead cases of disease, and even more noticeable as post-mortem changes advance. The kidneys appear to suffer very little from the general congestion which must be considered a symptom in Strongylosis. The colour of the kidney in a freshly killed healthy bird is a reddish brown, a good deal paler than the colour of the liver. Normally the lobes lie very flat against the dorsal wall of the abdomen, fitting into the inequalities of the skeleton. In the breeding season, and in a breeding bird, there can be no doubt whatever as to the sex, for the ovary is a conspicuous bunch of more or less developed ova in the hen ; and in the cock the testes are conspicuous round white objects as large as the kernels of good-sized hazel-nuts on each side of the backbone. There is but one ovary, and it lies always on the left side of the backbone of the bird. There are two testes, one lying on each side of the backbone, the left one generally at a slightly lower level than the right. This development of the ovary only on one, the left side, is the reason for advising the examina- tion to be made as described above, on the left side always. One testis or the ovary cannot then be missed. If the bird examined thus is not breeding, as may often be the case with birds found dead of disease in April and in May, the discovery of the ovary is still a matter of comparative ease, and the discovery of the testes even easier. The testes are always somewhat enlarged in the spring months, whether the bird be diseased or not, and they may be the size of a pea or larger, and will generally be white. The ovary may be small, but will always be like a portion of hard cod's roe, in which the ova, though no bigger than a pin's head, are distinct and numer- M 178 THE GROUSE IN HEALTH AND IN DISEASE ous. The undeveloped ovary of an adult female Grouse would about' cover a threepenny piece, but is long and triangular in shape rather than circular. The oviduct in a breeding hen is a large and conspicuous duct, and may, of course, contain an egg with the shell in course of formation and being pigmented in preparation for laying. The oviduct in a barren bird, or in a hen at other times than the breeding season, is a very much less conspicuous object, and is less easily found than the small and undeveloped ovary. If no ovary is seen, but a very small blackish, or whitish, or parti-coloured object is found in its place which is suspected of being a testis, the intestines must then be gently separated from their attachments about the middle line of the back, and the other testis must be sought for about in the same position on the opposite side. Even in a young bird the ovary shows ova with sufficient distinctness to make doubt as to its sex an impossibility ; but in a very young male bird the testes may be so small, and, being very often black, may look so unlike what is expected that both shotild be sought for and found before arriving at a certain conclusion as to sex. It is easy, if the intestines are roughly handled, and the attachments torn carelessly away, to carry away the testes or the oVary from their proper position, and to remove them with the intestinal attachments. The peritoneal folds are delicate and require careful handling, and they overlie the generative organs and the kidneys ; but a very little practice will enable any one to do the necessary dissection with certainty, and to arrive at an irrefutable diagnosis as to sex. The testes appear often to run a normal course of develop- ment as the breeding season approaches, however seriously the bird may be diseased. The first sign of any increase in the size of the testes is to be found about the third week of February, at least in the northern half of Scotland. Further south it is found a little earlier. In May the testes have increased in size to twenty or thirty times the bulk they had during inactivity, and they are then white and fatty, ANATOMY AND PHYSIOLOGY OF RED GROUSE 179 whereas in winter they arc generally small and black and deeply pigmented. Occasionally a very emaciated cock bird will be found with testes only half the normal size during the breeding season ; but, as a rule, the effect of disease on the development of the hen's generative system, both ovary and oviduct, is far more noticeable than is the case in the male. It is very noticeable that in sick Grouse hens there is no development of the ovaries or enlargement of the oviduct and cloaca such as takes place in spring in every healthy hen. The ovaries remain small and undeveloped as in midwinter. Such birds are barren if they pair, for as a rule they cannot lay an egg, but they pair nevertheless, as every gamekeeper knows to his cost. This difference between the male and the female Grouse is significant. It seems that, in the male, appearance may be sacrificed to efficiency, for in cases of disease the generative organs may be fully developed while the plumage is backward ; whereas in the female, appearance comes first, and the nuptial plumage is donned at any cost, often to the undoing of the hen herself, at any rate to the complete undoing of her power to produce an egg. There are, of course, many sicldy hens that not only don the breeding dress but also lay a modicum of eggs. They appear later in the shooting season with every sign of disease and exhaustion upon them, but yet recovering. Grouse that have survived the mortality of April and May do not usually die later in the year. They become con- valescent through the summer and autumn, owing to good food and better weather. There is, in fact, no autumnal outbreak of disease ; but there is an increased opportunity for the collec- tion of birds that have been sick and are convalescent. These birds can fly, and are shot in August and September ; it is only when they are discovered in the bag, in the process of inspection later in the day, that they are suspected of disease, and are forwarded to the laboratory for examination. 180 THE GROUSE IN HEALTH AND IN DISEASE Such birds are not at the point of death, but are, in fact, convalescent. They are not the birds that will be killed off necessarily in the coming winter, but may perhaps be still weaklings in the following spring. They are the birds that in the previous spring were badly hit by Strongylosis, but managed to survive April and May, and were then safe, with a supply of good and varied food assured to them for at least eight months to come.^ As we know much about these wasted autumn hens it is now safe to say that they may be placed in two classes : — (1) Those that were too sick in the spring to breed at all, and so remained barren. (2) Those that were not too sick to breed, but bred small clutches and reared from two to four or five young Grouse. The first class has the best chance of recovery, for with them there is nothing to occupy their attention but food and rest and their own convalescence. Probably most of these are passably healthy birds in autumn, with no sign of having suffered very badly except in their backwardness as regards change of plumage. These birds usually show a great mixture of plumages, having feathers sometimes of the preceding winter plumage, mingled with an irregularly grown nuptial spring plumage and perhaps some new feathers of the already overdue autumn-winter plumage. The second class is different. They also have a mixture of the same three plumages, but with more complete nuptial feathers, and fewer of the preceding winter plumage, They are the worst of all the sick birds seen in the autumn months. They may have been less sick in the spring than the barren birds but they have been completely worn out by the effort to nest, and by the cares of their family. They have nevertheless struggled through, thanks to the summer and autumn food supply and summer weather, and by the autumn they are convalescent. By January they will in all probability be once ' Vide chap. iii. pp. 84 et seq. ANATOMY AND PHYSIOLOGY OF RED GROUSE 181 more comparatively strong and healthy, but not so well pre- pared to meet the critical conditions of early spring as those included in the first class. These, probably, of the second class are the birds that form the first class in the following year, or perhaps they cannot even rise to that, and fall victims to the spring mortality. CHAPTER VII THE ANIMALS WHICH LIVE ON OR WITHIN THE GROUSE It is necessary to begin this short account of the animals which live on or in Grouse by apologising for the length of many of the words employed and in some cases for their technical nature. It has not been found possible" wholly to do without them, but in most cases the scientific names of the various animals mentioned .are given in footnotes, and an attempt has been made to explain the technical terms used. Like other animals, the Grouse supports a number of parasites living on or in it which we can collectively call its " fauna." On the outside of its skin, amongst the base of the feathers, numerous insects browse, whilst beneath the skin in the spaces of the body, such as that of the alimentary canal, and in the cells and tissues, such as the epithelium or lining membrane of the intestine and in the blood, worms and unicellular animals (Protozoa) swarm. During the last four years these parasites have all been investigated, some more, others less, closely, according as they seem to throw much or little light on the health and disease of the bird. In the account which follows the members of the Grouse's fauna are numbered consecutively so as to give some idea of its wealth and variety. The animals which live beneath the skin and within the body of the Grouse constitute the " Endoparasites " of the Grouse, whilst the animals that live on the outside of the skin are termed the "Ectoparasites." Amongst the last-named is included the Grouse - fly.^ This fly is said to suck the ^ Ornithomyia lagopodis, Sharp. 182 ANIMALS WHICH LIVE ON OR WITHIN GROUSE 183 blood of the Grouse, at any rate it is so constantly associated with that bird that it seems to merit a place here. At first sight the attention paid to the Ectoparasites, or animals which live outside the Grouse, mostly among the feathers, may seem superfluous, but the study was rendered necessary by the probability of establishing a connexion between these Ectoparasites and the more important internal parasites. Most of the internal parasites and all the tapeworms pass through a second host. For example, the tapeworms which live in the alimentary canal of the Grouse pass their younger or larval stages in the body of some lower animal. This lower animal, presumably an insect or a snail or a spider, must be eaten and digested by a Grouse, and the larval tapeworm must be thus set free before it can grow up into the adult tapeworm which we find in the intestine of the Grouse. In searching for this second host it was natural to begin with the Ectoparasites, which one would imagine were continually being snapped up by the bird. We have, however, up till now completely failed to find any tapeworm larvae in the Grouse-fly or in the numerous " biting - lice " or "bird- lice "^ which abound on the skin and amongst the feathers of the Grouse ; and what is still more significant and stiU more remarkable, we have, in the himdreds of crop contents which we have examined, never found one of these insects amongst the Grouse's food. During the course of the recent investigations many ana- tomical and morphological notes have been made which, though interesting to the zoologist, have no direct bearing on disease in Grouse, these have been published in another place.^ Here, it is proposed to give as complete a list as possible of all the animals which infest the Grouse, but only to discuss at length such facts as have a direct — ^though perhaps at times a distant — ^bearing on disease in Grouse. For there is no doubt that the worms and unicellular animals (Protozoa) which live in various regions ' These form the group of insects called the Mallophaga, which is allied to the Anoplura or true lice of man and other mammals. ^ Proceedings of the Zoological Society of London, 1909, pp. 309, 335, 351, 363. " The Grouse in Health and in Disease," First Edition, pp. 348ff. 184 THE GROUSE IN HEALTH AND IN DISEASE of the alimentary tract cause very definite and often very fatal diseases, and to diminish this cause of death the parasites must be eliminated or their access to the body of the bird prevented. Consideration of the diseases thus set up will come elsewhere, and here it should only be remarked that the expression " the grouse-disease " is a misleading one. As if a Grouse or any other living creature suffered from only one disease ! What is usually meant by "the" disease is a some- what sudden and very virulent disorder which sweeps through a district and in a very short time carries off a very large per- centage of birds. Such a disease was investigated by Dr Klein some twenty years ago, and it is proposed that this disease — if it be a distinct disease — be called Klein's Disease of the Grouse. Since the Committee was appointed there seems to have been no definite outbreak of Klein's disease, but innumerable Grouse have been examined which were said by the game-keepers and moor-owners to be affected with or killed by "the" disease, which further investigation has shown to have been done to death by worms or Protozoa. The symptoms of " the " Grouse Disease are not readily apparent, especially to the unclinical eye. ECTOPARASITES INSECTS. A. Mallophaga. — Bird-lice or Biting-lice. I. — Goniodes tetraonis, Denny. The Broad Bird-louse of the Grouse. The bird-Uce comprise a number of forms, sometimes also termed biting-lice, which in the great majority of cases live on the skin of birds. A few, such as the dog-louse,^ live amongst the hairs of mammals. As this is the alternate host of a common tape-worm,^ which passes its ^ TricJiodecks lotus, Nitzsoh. 2 Dipylidiwm caninwm (L.). ANIMALS WHICH LIVE ON OR WITHIN GROUSE 185 adult state in the dog, there was some justification for our hope of finding the larval stage of at least one of the Grouse tapeworms in these insects, but so far we have not succeeded in doing so. The bird- lice form a rather isolated group of insects ; but there is, apart from the fact that their mouth organs are adapted for biting and not for sucking, much resemblance between some of their organs and those of the true hce ; with these but not so closely allied, are the fleas .^ Biting-Hce are as a rule minute flattened httle insects, with poorly developed eyes, a chestnut-brown body, and a generally wefl-groomed appearance. Five distinct species infest the domestic fowl, and unless the host be unhealthy, they seem rarely to do much harm. In 1842 Denny ^ described and figured the broad bird-louse, which he calls the " Louse of the Black and Red Grouse." He states that it is " common upon both the Black and Red Grouse." ^ " Upon the Willow or Hazel Grouse* I find a similar but distinct species, rather broader in the abdomen, and of much darker colour." Andrew Murray, in his book on Economic Entomology,^ writing of the broad bird-louse, says : " This is the insect which sometimes, especially in the bad seasons, does so much harm to the young Grouse when they are feeble and unhealthy." Goniodes telraonis is the commonest of the insects which infest the skin of Grouse, crawling about amongst the bases of the feathers and on the vanes of the feathers themselves. It occurs more commonly than the narrow bird-louse of the Grouse,^ which is often associated with it. It is comparatively rare to find a bird free from these " biting-Uce," but perhaps 10 per cent, is about a fair estimate of the number of uninfested Grouse. The number on each bird is to some extent an inverse measure of jtheir health. Careful search wiU discover but two or three on a healthy Grouse, but on a " piner ".^^hundreds may be met with. The broad |bird-louse is^usually foimd^on"^theJsmaUer feathers, crawling"'about half-way between their insertion and the tip of their vanes. When disturbed they hurry away into the brushwood of the small feathers, like smaU deer seeking cover, and they are by no means so easy to catch as one at first thinks. They eat the finer barbules of the feathers, which, accumulating in the crop, gives the dark, curved marking in their rather transparent bodies. On this meagre and arid diet they seem to flourish, actively produce young, and pass through several ecdyses or changes of skin. The eggs are very beautiful objects ; in badly infested Grouse they may be numerous, but as a rule they are none too easy to find. Usually ' Bird-Hoe, true lice, and fleas are now placed together in the modern group Anapterygata. " "Monographia Anoplurorum Britannise," published by H. G. Bohn, London, 1842, p. 161, PI. xlii. Fig. 3. • Tetrao tetrix and Lagopns scoticus. * Tetrao saliceti (sic). » Chapman and Hall, London, 1877. ' Kirmus cameratus, Nitzsoh. 186 THE GROUSE IN HEALTH AND IN DISEASE they occur in small groups attached to the base of the after-plume and between it and the shaft of the plume. The specimen figured was on one of the feathers from the flank. (See PI. xvii. Fig. 4.) The eggs are elongated, some three or four times as long as they are broad. They are fixed by some adhesive secretion at the end corres- ponding to the hinder end of the embryo they shelter. At the other end is a well-marked cap or operculum which always points to the free end of the feather. The beauty of the markmg on the egg-case is shown best in another but aUied genus,' and we figure one, which we found 2 on the feathers of a partridge. Under the pressure of a coverslip the egg-case gradually ruptured along a circular line below the well-marked thickened edge or rim of the cap. The contained egg then began to emerge, carrying ofi with it the cap. The resemblance of this structure to a cap was emphasised by the long process which stands out like a feather borne on its apex. The eggs of the broad bird- louse of the Grouse show the network markings less well, but they are conspicuous on the cap, which bears a long tapering filament, longer than the egg itselE. These markings also occur just below the cap, but fade away towards the fixed end. The general appearance of the eggs on the after-plume is shown in PI. xvn. Fig. 3. They were found on the 27th July 1908, and they seem to be laid throughout the summer. There is no metamorphosis, thp young leaving the eggshell as miniatures of their parents. II. — Nirmus cameratus, Nitzsch. The Narrow Bird-louse of the Grouse. This insect seems to have been first named by Nitzsch' in the year 1818, but with no description. It is figured and described, and a bibhography is given by Denny * under the name of Nirmus cameratus. Denny found it on the Red Grouse, the Black Grouse, "and I expect also upon the Ptarmigan." Grube describes it in Middendorf's " Siberian Travels " as existiag on the Willow Grouse' and the Ptarmigan,'^ thus confirming Denny's surmise. This narrow bird-louse is mentioned in Giebel's article' on bird- Uce at HaUe, and described and figured in his great monograph.* Piaget in his " Les Pediculines," states his conviction that N. cameratus is specifically identical with the N. quad/rulatus of Nitzsch, from the Capercailzie." This opinion is also held by Kellogg.'" ^ Menopon, ^ This egg is almost certainly the egg of Menopon pallescens, Nitzsch. ' Germar's Magazin der Entomologie, Halle, iii., 1818, p. 291. ■* " Monographia Anoplurorum Britanniee," London, 1842, p. 112, ^ Lagopus albus., Lin. =Z. sub alpinus. Nils. ' Lagopibs mutus, Leach =i/. alpinus. ' "Zeitsch. Ges. Naturwiss.," xxviii., 1866, p. 370. ^ Insecta JEpixoa. ' Tetrao urogallus, '" Wytsman's Oerura Insectorum, 66th Fasc. Mallophaga. PLATE XVll. G0NI0DE8 TETRAONIS. Fig. 1. Goiiiodcs tctraonls. Denny. Male seen from abrive. The legs are shown on the left side only. The forked character of the antennie of the male and tlie male genital plates in the ahdomen are shoivn. Fk;. 2. Honioilrs Id raonls. Denny. Female seen from below. T\\r nnl)j-anclicd antenme and bitin<,' jaws are Wfll shdwn. 'ff,M y / Fk;. 3. Eggof Meno2)onpaUescens. Nitzscb. Highly niagnitied. Under the pressure of the cover-sli|> the operculum has come away and the egg is squeezing its way out of the egg-shell. F]i:. 4. Four eggs of Honimlcs tc/raciiis attached lo the base of an after-jihinie. The opei'cidum has fallen off one of tbeiu. Opposite p. 186.] PLATE XVlll. NIRMUH CAMERA. TUH. Tim m, V ('* ^ 7 ft II ^ Fig. 1. Mrmus camemtiis. Nitzscli. Magnified. Female. A seen from above ;. B seen fvoni lieneatli. A B Fig. 2. Eggs nf Xin/nis i-itmn-nl ns nil tlic leatliers of a yovmg Grouse abont tliree weeks iilil. A, \rry sbglitly inagiiilied, three eggs on one of the wing-eovers ; ]>, ver^^ highly niagnilied to show reticulations. Opposite p. 187.] ANIMALS WHICH LIVE ON OR WITHIN GROUSE 187 Nirmus is a more slender animal than Goniodes, and appears to be longer. It is rarer than the latter, though ia the great majority of cases the two are found together. Most of what has been said above about the broad bird-louse appUes also to the narrow form, as their habits are very similar, except that the latter lives more on the skin and upon the base of the shaft of the feather than does the former. It also seems to frequent the feathers under the wing, where the broader form is seldom seen. Both species appear to be able to wander all over the body ; and though they seem rather more common upon the head, neck, and back, the old view that these bitiug-hce occur chiefly or exclusively on those parts of the body inaccessible to the beak has not been borne out by recent investigations (PI. xvrn. Mg. 1). Some eggs of this form have been found. These were for the most part empty, but from one or two full ones specimens of the insect have been hatched out. The eggs are white, and transparent when empty, just visible to the naked eye, 0-6 mm. in length, and about four times as long as they are broad. Each egg-case is beautifully marked with a network of ridges, the areas between the ridges being six-sided. At one end the egg has a cap which is pushed off when the young emerges. The eggs are laid between the barbules of the feather-vanes or near the bases of the filo-plumes or short hair-Uke feathers, and adhere to their supports by means of some sticky excretion (PI. xvni. Kg. 2). The eggs appear to be laid during the summer ; the first time they were found (some of them were empty) was on 2nd July 1907, they were found again later in the season. There is no metamorphosis or change of the larva into a chrysalis, and then into the adult form, as for instance ia butterflies. The young emerge from the egg-case as small miniatures of their parents. They seem to cast their skin several times, but the exact number of times is not known. Dead specimens and cast skins were frequently met with. In no case were either of the two species found in the crop of the Grouse, though, as we have just stated, they are fuUy exposed to being snapped up by the bird's beak if the bird cared to notice them. It is not known exactly how clean birds get infected ; probably the bird- hce simply crawl from one bird to another when the latter are con- tiguous. There is evidence, however, that in some cases, probably rare ones, they cling to the Grouse-fly and are by it transported to a new host. B. SiPHONAPTERA. — Fleas. (i.) Fam. Pulicid^. — Fleas. III. — Ceratophyllus gallinulce, Dale.^ We are indebted to Mr N. C. Rothschild for identifying this flea, which is here recorded for the first time from the Grouse. It is a 1 N. 0. Eothsohild, Ent. Mag., 2nd Ser., xiv., 1903. In the Unt. net. xiii., 1901, No. 10, Rothschild described this under the name — synonym — of Ceratophyllus (Trichopsylla) newsteadi. 188 THE GROUSE IN HEALTH AND IN DISEASE well-kno-wn bird-flea, having been found in the nest of the hawfinch, in that of the dipper, in that of the blackbird, the moor-hen, and others. In the thousands of Grouse which passed through the hands of the Committee only one or two specimens of this flea were found (all in 1906), and none were found in the crop. Hence, although the dog-flea, Pulex serraticeps Gerv., is said to be the intermediate host of the dog tapeworm,! jt does not seem at present very possible that the Grouse-flea could play any part in the life history of the Grouse tapeworms. On the other hand a flea may easily escape notice in the crop contents, and this species is probably much commoner in the nests than on the birds when flying. It has been suggested that there may be a connexion between the seasonal occurrence of ^the transparent tapeworm and the life history of the flea. The view is strengthened by Minohin's recent discovery of the larval form (cysticercus) of a tapeworm ^ in an aUied species of flea^ which Uves on the rat. As this species of Grouse - flea had not hitherto been accurately flgured, Mr Edwin Wilson drew both male and female, and the drawings were reproduced in the original report. Now that the role of the flea in carrying certain human diseases is recognised, it is weU to have them accurately delineated, as in a flea every hair teUs. (PI. XIX. Fig. 2.) IV. — Ceratophyllus garei, Rothsch. This second species of flea was found in a Grouse in 1907 ; but only one or two specimens were taken. It is recorded by Evans * from the nest of the lapwing, and of the ring-dove. Rothschild^ has found it in the nest of a water-hen, and he records that it has been taken from the stoat, the weasel, the shrew, the vole, and the water-rat, and from hedge-chppings. C. DiPTERA. — Flies, (i.) Fam. Hippoboscid^. — Horse-flies. V. — Ornithomyia lagopodis, Sharp, — The Grouse-fly. This family iacludes besides the Grouse-fly, the horse-fly, sometimes known as the forest-fly, the sheep-ked, which has lost its wings and burrows in the wool of the fleece, and a third species which infests red- deer. This last has wings when young, but when the flies find a suit- able host they get rid of their wings and nestle among the fur. Moat, however, of the members of this family Uve on birds, and they seem particularly to frequent the swaUows and aUied species. ! Dipylidvu/m, caninum. ^ Thought by Mr NicoU to be HymenoUpis diminuta (Eud.), a tapeworm of the rat. ' OeratopJiyttusfaseiatus. ■^ "Ann. Scot. Nat. Hist.," 1906, p. 163. ■> Ent. Mag., 2nd Ser., xiii., 1902, p. 225. If PLATE XIX. C Ell ATOP HYLLUH GALLINUL.E, ETC. V'v^. 1. Tlii- fiiuu.se-lly Urni.thniiiiiiii luijnpoiUs. iMa^iiilinl almut nine tiincs. V»v Fli;. 3. Lana <.f Sail,)- pliinjii Kli'iciiriin'ri L. i'rii)ii a Gioiisf-dnipiiiiio. Ma,f,'ni(iijd. 'i.s. antf'iiur spitaclr-. p. a. posterior aidracle. Ii.s. liypostomal scleritc. pli.s. pharyngeal sclerite. v.t. viseral tracliea. t.c. transverse commissure. Opposite p. "■ ' Fie:. -I. mdc view of Ccm/i:plii//liis fiiij/iiiii/^r. Dale. Higlily magnilied. A, Male ; 13, Female drawn to tlie same scale and showing the relative difference and size. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 189 Till recently it had been thought that the Grouse-fly was the same species as the common bird-fly.i but recently Mr D. Sharp has pointed K^^*fl * it is a distinct species. It is distinguished from the common bu-d-fly by its " peculiar lurid blackish colour, without any trace of green even on the feet or legs," and by other characters which have been quoted in the more anatomical portion of the Committee's Report. Recently yet another species ^ has been separated off from the common bird-fly, so that we now have three species of Ornithomyia in this country, and probably more wiU be added as the group is further studied. We do not know the exact relations of the Grouse-fly to the Grouse. It is believed to suck its blood,^ and it certainly bites human beings. For a time it seems to burrow amongst the feathers of the bird, and any one handling Grouse during the summer is hkely to disturb a fly or two. They come buzzing out, and are apt to crawl up one's sleeve. The feet, although large, are very beautiful. They are provided with a pair of very large hooks (PI. xix. Fig. 1). Altogether, these insects have a sinister aspect, and to people who do not like flies they are very repellent. They occur freely in larders where freshly killed Grouse have been placed, and after a short time they leave their dead host and accumulate upon the windows. The earhest month in which the Grouse-fly has been found is in June, towards the latter end. The latest is in October. They are most plentiful in August. The females seem to be commoner than the males, or, it may be that in August they are more readily caught. Like other horse-flies, forest- flies, and sheep-ticks, the Grouse-fly does not lay eggs, but the ovaries produce one large egg at a time, and this passes into a dilated oviduct which acts as a uterus, and here the egg develops. After attaining a certain stage of development, the larva surrounds itself with a pupa or chrysalis skin and is extruded. The chitinous or homy covering of the larva hardens and blackens with exposure to the air, and forms the so-called pupa-case ; in fact, one may almost say the young are hatched as pupae. At no time is the larva exposed, though there is a larval stage free in the uterus of the mother wrapped first in the egg-shell and then in the pupa-case. The pupae were found during August and September. They are black, shiny, seed like looking objects, and appear to be deposited amongst the feathers, from which they are easily detached. The few we have found either dropped on some paper over which we were handling birds, or lay loose at the bottom of the cardboard boxes in which Grouse travel. Probably they take some eight or nine months before they give rise to the adult fly, and the latter very likely disappear altogether from about October tiU June. Further research is needed to throw light on these questions. Three specimens of the Grouse-fly, all of them taken from one bird, ' Ornithomyia avicularia, Lin. ^ 0. fringillina, Bezzi, 3 Proc. Zool. Soc. Zand., 1910, p. 704. 190 THE GROUSE IN HEALTH AND IN DISEASE were themselves markedly infested with an ectoparasite, a species of mite. Here we refrain from quoting Dean Swift. The mite i belongs to a sub-family all of which are parasitic upon insects ; these are re- garded as harmless. Our specimens existed in considerable numbers, clustered round the hinder end of the fly's abdomen on the ventral surface, with their snouts or proboscides plunged into the body of the insect. Many were laying eggs, and many cast-off cuticles were lying around them. Eggs from which the larvae had escaped presented a spindle-shaped outhne ; others contained eggs in various stages of differentiation ; others fuUy formed larvae. We have in no single case found a Grouse-fly in the crop of a Grouse, nor have yet found any cestode larvae or cysts in the bodies of the flies which we have cut into sections or dissected. (ii.) Fam. ScATOPHAGiDiE — Scatomyzid^. — Dung-fiies. This family contains species many of which produce their larvae aUve and deposit them in the bodies of other insects, or on open sores, or in organic material. The Grouse dung-fly. cannot be looked upon as an ectoparasite of the Grouse, but it lays its eggs in Grouse- droppings, and its maggots hve on and in these dejecta. The maggots must therefore constantly be in close contact with and certainly eat the eggs of the tapeworms which exist in such vast numbers in the Grouse droppings ; and hence it was thought a profitable object to investigate for the second state of the cestode. It may be recalled that each Grouse dropping consists of two parts — (1) the dejecta from the intestine strictly speaking, and (2) the more fluid dejecta from the caeca. The latter pass last and He like a cap upon the former. The two lateral diverticula or pouches of the bird's intestine known as the caeca are unusually large in the Grouse, and in them the absorption of the digested food takes place. The fly-maggots are only foimd in numbers in the " caecal " part of the dropping. VI. — Scatophaga stercoraria, Lin. — The Grouse Dung-fly. The Grouse dung-fly is first found commonly in AprU. In June it is not so common, owing perhaps to the rain having washed the caecal part of the droppings away. A large number of the larvae have been examined both by crushing them and by cutting them into sections, but no trace of tapeworm cysts have been found, although many weeks were spent in carefully searching through the tissues of this and an allied species of dung-fly. ^ No specimen of either dimg-fly or of their larvae has been found in the crop of the Grouse (PI. xix. Fig. 3). ' Mr C. Warbui'ton has kindly identified the mito as belonging to the genus Canestrinia and probably to a new species. ^ Scatophaga squatida, Meigen. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 191 ARACHNIDA. AcARiNA. — Mites and Ticks, (i) Fam. Ixodid^. — Ticks. The ticks are now known to carry certain unicellular animal parasites (Protozoa), capable of setting up virulent disease in man, cattle, dogs, etc. They may therefore be of importance in an inquiry into Grouse Disease. It is possible that their presence on the skin may be connected with some of the internal protozoal parasites mentioned below. Severe outbreaks amongst fowls of a disease named " spirillosis " and of another obscure but very often fatal disease have been described by Balfour^ in the Sudan. The organism which causes the former disease, a spirochaete^ is transferred from one fowl to another by a tick.^ The second, and as yet rather obscure, disease is recognised by the natives, and by them associated with the presence of the same or allied ticks. We have found little trace of such disease in Grouse, and the recorded number of ticks taken in the Grouse is, except locally, so small that they can hardly play any part in Grouse Disease. VII. — Ixodes ricinus, Lin. — The Common Sheep-tick. This species of tick (the "castor-bean tick," as it is called in America) is common in many parts of the world. It is reported from sheep, goats, cattle, horses, deer, dogs, cats, foxes, ferrets, hedgehogs, hares, rabbits, bats, birds, and man. It occurs most frequently during the spring and early summer, but disappears after the beginning of July. The sheep-tick is one of the commonest and one of the oldest known ticks of Europe. In the British Isles it often occurs on hunting dogs, and is sometimes called the " dog-tick " ; the adult stage is especially frequent on sheep, goats, and oxen ; less common on horses, dogs, and men. On the other hand, the larvse and the nymphs are common enough on birds, lizards, and small mammals — in fact, on animals which live among and brush through grass or heather. It is only in the larva and nymph state that we find these ticks on the Grouse. On each of the infested birds the specimens were fixed on the chin or romid the eyelids — ^in fact, in such positions as the Grouse cannot reach with its beak. In parts of Ross-shire, especially in certain woods, these ticks swarm in enormous numbers, and the keepers declare that they kiU large numbers of young blackgame. Hence there is nothing remarkable in finding this species from time to time ' British Medical Journal, 9th November 1907, No. 2445, p. 13S0. ^ ViobaXAy S-pirocliixta gallinarum, * Argas persicus. 192 THE GROUSE IN HEALTH AND IN DISEASE on the Grouse, where its presence must be regarded as accidental. The larval stages emerge from the eggs and probably crawl on to the heather, and thence on to the Grouse or other animals which come in contact with the vegetation. Both larvae and nymphs have been found amongst the feathers, but in small numbers and on rare occasions. The tick has never been found in the crop, and it can hardly play any part in infecting the bird with tapeworms. (ii.) Fam. TyroglyphidjE. — Cheese and Flour Mites. VIII. — Aleurobitis farince, de Geer. — The Flour Mite. Synonym : Tyroglyphus farince. Gerv. Mr C. Warburton has identified this small mite which was found in considerable numbers on several birds and at varying times of the year. Whilst very common at Easter time, they were less abundant in July. The flour-mite occurs iu great numbers on all sorts of organic material — grain, straw, hay, tobacco, flour, cheese, dead bodies, etc. At times the workmen handling com, horses, etc., have suffered much irritation and skin - eruption from the attacks of this mite. There seems no doubt as to the species of this mite, but the authorities on these animals express surprise that they should occur so commonly on the Grouse. They have, however, been found on a large majority of birds which were specially searched with the view of findiag mites. The specimens, some of which were taken on freshly kiUed Grouse, contained some red substance'in the stomach, probably blood from the bird. There seems at present little reason to incriminate this mite as the carrier of the tapeworm cyst. ENDOPARASITES PLATYHELMINTHES.— Flat Worms. Cestoda. — Tapeworms. In the alimentary canal of the Grouse are found three species of tapeworm, two of the genus Davainea and one the genus Hymenolepis. Before describing the tapeworms of Grouse in detail it is necessary to refer once more to the method by which they are reproduced. As already stated, we know that all tapeworms, ANIMALS WHICH LIVE ON OR WITHIN GROUSE 193 with perhaps the exception of one species, pass through two distinct and different animals known as hosts. Unfortunately, little or nothing is known about the life- history of any species of Davainea which includes both the " large " and the " stumpy " tapeworm, or of Hymenolepis, the " transparent " tapeworm of the Grouse. The larval or cystic stages of the former have in some few cases been said to occur in insects and in molluscs; the larval host of the latter is thought to be an insect or a myriapod, or perhaps even more likely some "water-flea" or other fresh-water crustacean. With regard to these possible second hosts. We have never foimd a myriapod in the crop of the Grouse, and so far we have not found any Crustacea — ^though it must not be for- gotten that these are probably so small as to escape notice in the crop contents. Specimens of slugs belonging to a species ^ which is common on the Staffordshire Grouse moors have been found in the crop of a Staffordshire Grouse. These slugs are very voracious and practically omnivorous ; they will eat almost anything, especially decaying animal and vegetable matter, fungi, paper, weak and injured worms and slugs, and — what is interesting from the point of view of the Grouse tapeworms and round -worms — they devour the dejecta of other animals. They prefer the shady places in moors and fields, and emerge into the open only at dusk or when the day is cloudy or overcast. These slugs have been cut into sections and diligently searched for cysts of tapeworms, but none have been found. This absence of infection, combined with the rarity of the slug in the Grouse's crop, seems to show that it is not the second or larval host of the Grouse cestodes. Moorland streams have been tow-netted for Crustacea in the spring and a certain number of the larvae and adults of some of the water-fleas and other small Crustacea^ have been found. 1 Mr W. E. OolUnge has identified this slug as Arion empiricorwm, Ferussao. ' Mostly belonging to the genus Cyclops. A list of species captured, for which we are indebted to Mr D. J. Scourfield, is printed in the Zoological Society's Proceedings for 1909. N 194 THE GROUSE IN HEALTH AND IN DISEASE The numbers were, however, meagre and tow-nettings later in the summer yielded an even more unsatisfactory " bag." None of the Crustacea ^ when examined microscopically showed any cysts, and as they are few in number it seems improbable that the source of the tapeworm infection lies here. We have thus with some degree of probability shut out as second or larval host of the tapeworms — at any rate for the present — ^the ectoparasites of the Grouse, the myriapoda and the slugs or snails and fresh-water Crustacea, and this on the grounds (1) that on examination none of them reveal a cyst, and (2) that these animals are either not eaten by the bird, or so rarely eaten and in quantities so small as to render it highly improbable that any of these invertebrates could account for the almost constant presence of the tapeworms in large numbers in the Grouse. Two rather striking facts seem to point to the normal insect food of the Grouse, which it picks up on the moor, as the more probable source of tapeworms. One is that two artificially reared Grouse which died during the early autunon of 1907, when carefully searched for tapeworms were found to be entirely free from them. The second fact is, that under natural con- ditions young Grouse often contain fully grown " large " tape- worms (Davainea) before they are three weeks old. They must certainly have swallowed the second host when very yoimg, perhaps even the day they were hatched, or the worm would not have had time to grow. The young birds live very largely on an insect diet. Hence the best chance of finding this second host is to examine the crop contents of the very young birds, and to do this the observer must have a moor at his dis- posal, with leave to kill as many young birds as he may want, and this is a very difficult thing to obtain. It has been stated over and over again by sportsmen and gamekeepers that the Grouse eats no insects, but this is far from the truth. ' A fuller report on the insects found in the Grouse-crop has been given by Mr J. 0. F. Fryer. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 195 Although the observations on the animal food of Grouse are necessarily incomplete,^ enough has been done to show that it is fairly abundant and very varied. From the crop of a single bird there have been taken six saw-ily larvae, eight caterpillars of a Geometrid moth, one caterpillar of a smaller moth, two small Tineid moths, a number of immature bugs resembling the " frog " or " cuckoo-spit," a fly, two specimens of the plant-lice, one small spider, and the remains of four specimens of the slug mentioned above The gizzard of the same Grouse contained, in a more broken up condition render- ing identification more difficult, two or three dozen larvae of saw-flies and moths, some young bugs, and the pupae of two true flies. The segments of the Grouse tapeworms containing the ripe eggs pass away with its dejecta and lie on the ground or lodge on the heather and other plants, or in water. As already stated, the eggs of the two species of Davainea are believed to develop into larvae inside the body of an insect or a land mollusc. They are excessively minute, and lying as they do in millions on the heather, may be readily consumed by the leaf-eating cater- pillars and other insect larvae which live on the moors. Doubt- less many are eaten by the Grouse themselves, but these are digested and come to nothing, for they have not reached the larval stage and, as we have said above, the larval stage of a tapeworm must be passed inside an animal quite distinct from that which harbours the adult worm. To get at and eat the eggs seems an easier matter for caterpillars and other insect larvae or for slugs than it is for the ectoparasites, which as a rule are not very likely to come across the dejecta of their host. For this reason, in continuing the search for the larval tape- worm, it was necessary to examine the insect larvae and the slugs eaten by the Grouse. A common food of Grouse is the head of certain species of rush.^ There is a very minute moth ' See pp. 101 et seg. 2 Jy/ncus articulaius v. lamprocarpus, J. squarosus, and J. effusiis v. cmglomeratvs are all frequently eaten. 196 THE GROUSE IN HEALTH AND IN DISEASE whose larvae live in curious, white, papery cases inserted into each twig of this rash-head which they eat. When the rush is in its turn eaten by the Grouse, the larvae of the moth pass into the alimentary canal of the bird and are there digested.^ The case is whitish, semi-transparent, and with brown specks : it is formed when the larva is no longer young, but not at any very fixed time. At first its outer end is closed. The larva often leaves the case, burrowing into the rush-head for food, and at times fails to find its way back. Before pupating, the outer or anal end of the case is opened, and the case strengthened by a glandular excretion. In the Interim Report of the Com- mittee it was recommended that these larvae should be searched for cysts; but it has been pointed out that there would be little chance of the larvae coming across the eggs of the tape- worm as they feed in and on the interior of the rush-head, and the search has yielded no results. In following up this second line of research the insects which occurred most commonly in the crop of the Grouse were examined first. These were examined microscopically, both after teasing the body up in glycerine and by grinding it up — but not too finely — in a pestle ; in some cases also sections were made and examined, but always without result. In hunting for the cysts the observer meets with two great difficulties: firstly, it is not exactly known what the cysts of either of the tapeworms are like ; and, secondly, the tissues of the insects and spiders which were examined are little, if at all, known, and more than once some organ proper to the insect has been taken at first sight for a tapeworm cyst, only to result in the disappointment of finding later that it was an egg or other structure belonging to the putative host. A considerable number of the commoner insects found on ' It has not yet been possible to determine iinally the species of the moth, but it is probably Coleophora ccespititiella, for this species frequents many kinds of rush ; whereas the C. glaucicolella, the other inland species, is most partial to Jwncus glaucus. The former is usually fully out by the middle of June and lingers on till the middle of July ; the last-named moth issues about the middle of July, and flies for four weeks. J. H. Wood, Ent. Mag., 2nd Ser., iii. (xxviii.), 1892. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 197 the moors have also been examined in the hope of throwing some light upon the life history of the Grouse tapeworms. The specimens ^ investigated were collected by Mr P. H. Grim- shaw, of the Royal Scottish Museum, but here again the investigation has not met with success. We may now proceed to describe the tapeworms of Grouse. Fam. TaeniidjE. XI. — Davainea urogalli (Modeer, 1790.) — (The "Large" Tapeworm of the Grouse.) Of the three tapeworms which are found in Grouse, this species, originally described from Lagopus scoiicus in 1853, by Baird is the commonest and by far the largest. It occurs in many allied forms, e.gr., the blackcock, the capercailzie, and according to Krabbe in a partridge, and one of the Himalayan pheasants. It appears at an early age in the young Grouse : a specimen, 35 cms. in length, has been taken from the intestine of a bird about three weeks old. Curiously enough, it was an abnormal specimen, the worm having split ; and ^ In the manner indicated, the following inaeets were examined in every case by looking through the debris of some four or five specimens. DiPTEKA. (i.) Monophilus ater, one of the sub-family Limnobiinse of the Tipulidse. Avery common constituent of the food of young Grouse. No trace of a cyst was found, but in one specimen an immature nematode was wriggling about. (ii.) Sibio sp. This also proved a blank. (iii.) Cyrtoma spuria, one of the Empidee. This fly is small and seemed to have little interior ; no trace of a cyst was found. In another small Empid fly a Gregarine was discovered. (iv.) Scatophaga sp. Scatophaga stercoraria is perhaps the commonest fly in Scotland, and, owing to its larvae living in the droppings of the Grouse, it can hardly fail to contain the eggs of the oestodes ; but no Scatophaga has ever been found in the crop of a Grouse, and there is some reason to doubt if the tapeworm eggs develop in this fly. After searching for a long time through the tissues of many specimens of Scatophaga, only one ovum was found, apparently of Davainea urogalli, and that was no farther advanced than when it was laid. Plkcoptbha. Similar gropings through the disjected membranes of an unknown species of Perlid produced no better results. Arachnida. The tissues of a spider very common on the moors, and of a phalangid were also investigated with a similar want of success. 198 THE GROUSE IN HEALTH AND IN DISEASE although one end of the fork of the now Y-shaped worm dwindled and came to nothing, the other was already shedding mature " proglottides " or " segments " crowded with eggs. The large tapeworm occurs oi^y in the small intestine of the Grouse. Sometimes the number of specimens is small, two or three ; at other times — and this is especially the case with weakly and diseased birds — the number of worms amounts to dozens, and they so fill the lumen of the ahmentary canal that it seems difficult to imagine how the food can squeeze past them. In a badly infected bird worms of very different sizes are met with. The anatomy of this form has been fully described in the Official Report : here we need only consider a few facts of more general interest. Both the " rosteUum," or protrusi- ble anterior end of the head, and the four suckers are armed with hooks. We shall consider later howf ar these hooks can act as inoculating agents. The number of proglottides or seg- ments varies with the size of the worm. The medium-sized speci- mens possess some two hundred and fifty proglottides — the long worms may have four hundred (see Fig. 16). The posterior proglottides are continually breaking off, singly or in short chains of two or three, and, leaving the intestine of the Grouse with the dejecta, they come to Me about on the moors. Each proglottis contains, at a very rough estimate, some two hundred eggs, so that at any given moment a D. urogalK would contain nearly one hundred thousand eggs. But this is no measure of the fecundity of the tape-worm, because as fast as the proglottides break off at the tail end new ones are formed at the head end, and the animal goes on and on producing new proglottides Hke a recurring decimal. The ova are excessively smaU, and they must be disseminated in miUions all over the moors. As already explained, they probably make their way into some imsect spider or mollusc, and there turning into the cystic or larval stage await the moment when the insect is swallowed by a Grouse to assume agaia the adult characters. An enormous number of the eggs must perish without ever meeting with those conditions which alone permit them to develop. Fig. 16. Davainea urogalU. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 199 X. — Davainea cesticilliis (Molin), 1858. (The Stumpy Tapeworm of the Grouse.) A second much smaller form of tapeworm also belonging to the genus Davainea has only been recorded twice ia the course of the iavestiga- tions of the Committee. Once a few specimens were taken from the duodenum of a Grouse shot in Roxburghshire ; and it again was found loose either " in the small intestine or rectum " of a Grouse from Caithness. In both cases only young, immature specimens were met with. It is remarkable for its short, stout, stiff appearance, and for its small number of segments. This tapeworm, common in chickens and turkeys, is only an occasional parasite of the Grouse, and in no case has its presence been associated with any lesions or ulcerations of the intestinal wall. As a factor in " Grouse Disease " it may be neglected. Its second host is probably some Coleopteran (beetle) or Lepidopteran (butterfly or moth), but at present this has not been proved. XL — Hymenolepis microps (Diesing), 1850. (The Transparent Tapeworm of the Grouse.) Specimens of a second genus and a third species of cestode inhabit the intestine of the Grouse. The same worm has been described from the capercailzie, and from the blackcock. The hving specimens of this tapeworm have been found only in that part of the intestine known as the duodenum, but after the Grouse is dead they may wander into other parts. It is an extremely deUcate, transparent tapeworm which exists in almost countless numbers in the duodenum of the Grouse. On cutting open this part of the alimentary canal of a Grouse infested with these worms — and it is seldom that a bird is found free from them except in the winter months — ^they are not at first apparent. They are so fine and so transparent that they are invisible when ahve, and the contents of this part of the alimentary canal appear very much like a thick soup. If we add some fixing agent such as corrosive subUmate this soup resolves itself into a mass of very fine, dehcate, white threads inextricably tangled up together, and so numerous that there seems but httle room left in the duodenum for the passage of the food. If, with great care — ^for they break at the shghtest strain — ^we succeed in disentangling one of these worms we shall find its head embedded to a greater or less extent in the mucous lining of the duodenum, into which, to use a poetic phrase, " it nuzzles " whilst the body of the wonn floats freely in the fluid contents of this part of the alimentary canal. If we also succeed in freeing the head we now have a complete worm, and can study its structure. {See Fig. 17.) We have no information about the fate of the eggs and embiyos of 200 THE GROUSE IN HEALTH AND IN DISEASE this transparent tapeworm, but as a general rule the cystic forms of this genus live in some insect or myriapod (centipede), as is shown by the fact that this genus of tapeworm occurs in bats, insectivores, rodents, and insectivorous birds. One species, Hymenolepis nana, occurs in man, most frequently in children, and is not at all uncommon in Italy. Sporadic cases of another species, H. diminuta, occurring in man, are also recorded. There is some evidence that the larval stage of this last-named species, which is common in rodents, occurs in the flea. Fia. 17. Hymenolepis microps. The injury caused by the presence of this tapeworm is serious, and when it is present in certain numbers it is associated with the occurrence of bacteria in the tissues, the number of which bears some direct propor- tion to the degree of infection of the tapeworms. That the latter should disappear during the winter is a curious fact which requires elucidation. Nematoda. — Threadworms or Round Worms. (i.) Fam. TRICHOSTRONGYLID.ffi. XII. — Trichostrongylus pergracilis (Cobb.i). (The Strongyle of the Grouse.) A '^^}i *^^ ^^^^^L P^^asite worm discovered by Cobbold and foS ^i *"^r/f ^- J^^l^'^g^ t° ^ g«^"« peculiarly destructive to burds. Some details of the harm caused by its near allies have been given m the Report of the Committee. .f Tlie strongyle lives in the opaque fluid contents of the paired cjeca of the Grouse. It is very thm and fine, and is d ifficult to see when ^ Synonym : Strongylus pergracilis, Cobb. 2 The "Grouse Disease," The Field Office, London, 1873. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 201 alive, owing to its transparency. On shaking up some of the contents of the caecum in 75 per cent, alcohol to which has been added a few drops of corrosive subhmate and acetic acid, the worms become opaque and more visible, and they can be easily seen by compressing between two microscope slides a drop or two of the csecal contents and holding them up to the light. The worms, if there be any present, then appear as thin, white transparent lines. The males are some 8 mm. ui length, the females 10 mm. No one has ever seen, and probably no one will ever see, this strongyle enter the body of a Grouse ; but that it does so in the larval form, and that directly, i.e., without the intervention of an intermediate host, seems clear. When swallowed the larvae make their way along the alimentary tract and turn up into the caeca, where they rapidly develop into adults. The serious injuries caused by the presence of T. pergracilis in the caeca, the accompanying symptoms, and the general pathology are described ia chap. vui. To distinguish the disease from others which afflict the Grouse, it may be called Strongylosis. (11.) Fam. Strong YLID.S. Xni. — Syngamus trachealis (Von Sieb). (The Red or Forked Worm.) This common pest of the fowl-yard and pheasant-coop has been found but three times in the Grouse. Probably the free and unconfined hfe of the bird, together with the comparative paucity of earthworms in the moors, protects Grouse from " gapes," as the disease caused by the forked worm is called. There seems no reason at present to incriminate this worm of causing any trouble to Grouse. One of the cases observed was a young bird from Argyllshire. (Hi.) Fam. TkichosomidjE. This family includes two human parasites, the whipworm of man and the worm which lives in the human intestines, and as larvae migrate to the muscles, causing the painful and ofttimes fatal disease of Trichinosis in man, pigs, and rats. The genus Trichosoma occurs in all classes of vertebrates, especially in mammals and birds. It includes some seventy different species. XIV. — Trichosoma longicolle (Rud.). (The Whipworm of the Grouse.) This round worm is far less common than the Strongyle. It occurs, in fact, sparingly, sometimes alone, sometimes associated with the transparent tapeworm, but always in the duodenum. The male 202 THE GROUSE IN HEALTH AND IN DISEASE worm is some 20 mm. in length, the female twice as long ; they are extremely thin, and resemble short lengths of very fine white silk. Like other members of the family TrichotraoheUdse the anterior end of the Grouse whipworm, for about one-fifth of the whole body- length, is narrowed Hke the lash of a whip. The males are much rarer than the females, and seem to occur, as far as our experience goes, in the proportions of about one to from seven to ten of the females. The eggs, which are very characteristic of the family, do not segment in the body of the female ; in fact, no egg of this species has been seen segmenting. Like the eggs of other members of the family they probably do not develop imtil they get into water or damp earth. They probably pass directly into the bird, without the mediation of any secondary host, and they infect it at a very early date. They have been foimd.in Grouse-chicks only two weeks old. This worm does not seem to be associated with any grave disease, though where it is present there is a great destruction of the epithehal ceUs lining the duodenum. Masses of epithelial ceUs, singly and in clumps, are found in the fluid contents of the intestine, and these can hardly be due to post-mortem digestion, as we find them in birds opened immediately after death. (iv.) Fam. Ascarid^. XV, — Heterakis papillosa (Bloch). Stossich mentions this round worm, as occurring in the Grouse. It is a very common parasite in poultry and pheasants. We have not yet met any examples of it in wild Grouse, but it has occurred in hand-reared birds. (v.) Fam. FiLARiiD.^:. XVI. — Filaria smithi. Dr Sambon has described under the above name, a " microfilaria " or larval form of some species of Filaria in the blood of Grouse. The adult forms of such larvae usually live in the Ijrmphatics and subcutane- ous tissues ; their larvse pass into the blood, and are conveyed to new hosts by some blood-sucMng insects. PROTOZOA. The great group of Protozoa, or unicellular, animals contains many parasitic forms which give rise to the most dangerous diseases. Sleeping sickness and malaria in man, biliary fever in horses, Texas fever in cattle, Coccidiosis in rabbits, Micro- sposriidois in bees, are evidence of this. Although already some ANIMALS WHICH LIVE ON OR WITHIN GROUSE 203 eight Protozoa have been described from the various tissues and organs of the Grouse, so far only one, Coccidium avium, has been associated with distinct virulent disease, and this parasite causes the death of many young birds. In dealing with the Protozoa it has proved quite impossible to avoid scientific and technical terms, they are indeed the only words which exist for describing the organisms in question. These terms have been explained in the original Report of the Committee.^ ORDER I.— LOBOSA. XVII. — Amoeba {Entamoeba) lagopodis (Fantham, 1910). Specimens of amcebse have been found in the fresUy deposited droppings from Grouse, and presumably the amcebse came from their alimentary canals. This amoeba has also been found in the rectum but rarely. It has never been found in the contents of the smaU intes- tine. Certain species of amoeba are pathogenic, and give rise to dysentery and other disorders in man. There is no reason to believe that the amoebae found in Grouse were the cause of disease such as that known as " blackhead " in turkeys, which was formerly thought to be due to an amoeba. It is now known that " blackhead " is a form of Coccidiosis — -the so-caUed amoebae in turkeys being a stage in the life history of a Coccidium. ORDER II.— SPOROZOA. Sub-Order I. — Gregarinida. XVIII. — Monocystis (sp). Some spores of a Gregarine, abnost certainly those of Monocystis, and probably of one of the .species inhabiting the earthworm, have been observed in Grouse. Grouse do not often eat earthworms ; in fact there are, as a rule, few earthworms for them to eat on Grouse moors, though this is not perhaps so true in the lowlands and in England as further north. Where, however, earthworms abound, the soil is full of gregarine spores which might easily be picked up by a Grouse. They are but accidental parasites, and seem to cause no harm. We have foimd them in the intestines of three birds. 1 See also Fantham, Proc. Zool. Soc. Land., 1910, pp. 672-722. 204 THE GROUSE IN HEALTH AND IN DISEASE Sub-Order II. — Hjbmosporidia. XIX. — Leucocytozodn lovati (Selig. and Samb.). This Protozoon, a species of Leucocytoziion, one of the Hsemosporidia, was first found in 1907 in the blood of a Grouse. Since then it has been observed^ alive in two birds, and in stained smears of the blood of two other birds. A new feature in the Ufe of the Leucocytozoa of birds was the discovery by Dr Fantham of the young multipUcative stages of the parasite in the spleen of the Grouse." Few birds are infected, and in the cases observed the degree of infection was slight. The parasite causes a certain amount of destruction of the colourless blood corpuscles ; but is not sufficiently common to cause more than a sporadic and slight amount of disease. XX. — Hcemoproteus mansoni (Samb ). This second parasite of the blood corpuscles was first recorded by Dr Sambon, who has seen something which he thinks to be stages in its life history in the body of the Grouse-fly. Some minute parasites seen since by Dr Fantham in the red blood corpuscles of two birds may be young forms of this species.^ Sub-Order III. — Coccidiidea. XXI. — Eimeria (Coccidium) avium. This is a dangerous parasite, and its presence is associated with much disease and frequent death in the young birds during the first few weeks of their life. The disease is of a very definite character, and is termed Coccidiosis. The parasite occurs especially in the duodenum and in the cseoa, and by entering, growing and multiplying in the epithelial cells of these regions of the alimentary canal it destroys the filling membrane. The spores are taken up direct from the ground or on the food, and the action of the pancreatic juice dissolves the spore- cases and sets free the parasites to attack the epithelial cells. It has been found possible to infect young fowls and young pigeons with this parasite of the Grouse, and to set up fatal disease. In all cases the birds suffer from enteritis, accompanied by acute diarrhoea, and the dejecta contain millions of spores which thus are spread all over the ground ; the spores pass uninjured through the intestine of the larvae of the dung-fly,* and these maggots which five in Grouse droppings may thus help to disseminate the parasite. For further details of this organism reference is made to chap. ix. on Coccidiosis. ^ See Fantham, Froc. Zool. Soc. Land., 1910, p. 693. " iSee Fantham, Ann. Trap. Med. and Parasitol. , iv., 1910, p. 255. ' See Proc. Zool. Soc. Land., 1910, p. 697. * Scatophaga stercoraria. ANIMALS WHICH LIVE ON OR WITHIN GROUSE 205 ORDER III.— FLAGELLATA. XXII. — Trichomonas eberthi. A small flagellate has been found in the contents of the caeca and intestine of several apparently healthy birds. This flagellate is either the same as, or is only a variety of, Trichomonas eberthi, which has been recorded from the cseca of fowls. XXIII. — Monocercomonas (sp). Forms of this parasite were also seen in the Grouse. They did not occur in very large numbers. ORDER IV.— SPIROCH^TACEA. This group includes such forms as cause relapsing fever in man and in fowls, and syphilis in man. The Spirochsetes are dangerous parasites when occurring in large numbers in the blood. Two species of Spirochsetes were found in Grouse, on a few occasions, both species being new. XXIV. — Spirochceta lagopodis (Fantham, 1910). This parasite was found in small numbers in the blood of two birds. It caused a slight alteration in the relative constituents of the blood, but was not associated with any specific disease. XXV. — Spirochceta lovati (Fantham, 1910). This species was seen alive and in stained specimens. It occurred in the cseca and intestine of six or seven of the many birds examined, and was not specially associated with disease. The protozoal parasites of Grouse mentioned above are described by Dr Fantham in greater detail, with illustrations, in the original Report. CHAPTER VIII -CONTINUED STRONGYLOSIS ^ Part I. — Effect of Strongylosis on the Grouse The round worm Trichostrongylus pergracilis was first described under the name of Strongylus pergracilis, by Cobbold. T. pergracilis is an extremely fine worm, measuring in the male from J to | of an inch, and in the female from | to | inch. They are very narrow and hair-like, and, as a rule, whitish in colour, but sometimes have the tinge of blood when seen in a very thin layer on a slide through the microscope. The extremely fine head and neck, finer than the finest needle, readily penetrates into the tissues of the csecal walls. The worms are very transparent, clearly revealing their internal structure, and they are so soft that the pressure of a cover- slip almost always ruptures them. The cuticle is very clearly and definitely ringed, and the rings are so constituted that whilst the worm can easily work its way forward through a tissue, it would have difficulty in wriggling backward. The rings give the edge of the body a strongly serrated appearance like a saw. This is most marked a little way behind the head, and extends over about one-third the body length. There is no trace of longitudinal marking on the cuticle. The general appearance of the worm when seen under the microscope is shown on the accompanying figures, and a detailed description of its anatomy is given in the original Report.^ 1 The term " Strongylosis " is employed in this chapter to denote the disease caused by Trichostrongylus pergracilis (Cobbold) ; though it would perhaps be more strictly correct to name the disease Trichostron,gylosia. ^ Report, vol. i. pp. 209 et seq, 206 "GROUSE DISEASE "—STRONGYLOSIS 207 I I. Pig. 18. Male Tricho- strongylus pergracilis, showing m mouth, alimentary canal, spicules, and genital bursa. Magnified. Fie. 19. Female T. pergra- cilis, showing an. anus ; c gl. cephalic glands ; m. mouth ; oe. oesophagus ; of. ovejector ; 0. ovary ; r. rectum ; ut. uterus with segmenting eggs; V. vagina. Magnified. @ ut^ U,tr Fig. 18. ti^. 19. 208 THE GROUSE IN HEALTH AND IN DISEASE Specimens of T. pergracilis are found in the caeca of most Grouse. They have been found, with hardly an exception, in every one of the two thousand Grouse examined by the Committee. They are apt to cover themselves with mucus and dirt, and are consequently hard to see, and are often over- looked. But they may be rendered opaque and white, and hence much more apparent, by shaking up the contents of the caecum in 75 per cent, alcohol, to which a few drops of corrosive sublimate have been added. Their presence is also readily detected by compressing a drop or two of the caecal contents between two microscope slides and holding them up to the light. The worms, if there be any, then appear as thin, white, transparent lines. A small pellet of the csecal contents, such as can be carried away on the point of a needle, when spread out under a coverslip, will, in a well-infected bird, show some twelve to twenty worms and one hundred to two hundred eggs in the field of a two -thirds inch Ross's objective with a No. 2 eyepiece. For the purpose of ascertaining the exact numbers of this worm in a single specimen a method of isolating and counting them has been devised and found to be practicable. The method is as follows: The caeca are laid out straight on a board and opened throughout their length, their contents are turned out, and all the material liable to contain Strongyli is collected. Small quantities are shaken up with water in a large test-tube, and poured out little by little into a Petri dish containing water. With suitable illumination the Strongyli can be clearly seen and picked out with a mounted needle and counted. As may be seen, by reference to Table I., in all but two birds (Nos. 57 and 67) approximately equal numbers of the worms are present in each of the two caeca. Strongyli are almost constantly present in the caeca of wild Grouse believed to be perfectly normal, and certainly of fair weight and in good general condition. In a few so-called healthy birds they may be present literally in thousands. GROUSE DISEASE "—STRONGYLOSIS 209 but they are more numerous in diseased than in healthy- birds. TABLE I. — Showing the Results of counting the Stronqtli in the TWO C^CA SEPARATELY. Strongyli. Grouee No. Total. One Ciecnm. Other CEecnm. 52 81 58 54 59 113 65 89 94 183 59 108 127 235 46 131 128 259 55 201 214 415 63 281 252 533 64 268 303 571 57 331 268 599 62 365 375 730 67 285 548 833 68 420 457 877 66 455 490 945 56 754 1,114 1,868 53 1,103 1,403 2,506 60 3,118 2,877 5,995 61 4,769 4,793 9,562 Table II. shows that the number of Strongyli present in diseased birds, though varying considerably, is greatly in excess of that found in the great majority of normal birds. In a small minority of the presumably healthy birds the numbers were as large as those foimd in many of the diseased birds. It is, of course, impossible to be certain that these exceptional birds were not really suffering from the early stages of " Grouse Disease." The two (Nos. 60 and 61) with the largest numbers came from a moor on which " Grouse Disease " was prevalent at the time. The presence in diseased birds of Strongyli in numbers far in excess of those found in normal birds does not, of course, o 210 THE GROUSE IN HEALTH AND IN DISEASE prove that they were the cause of the disease, because it is conceivable that they may have multiplied as a consequence of the disease. Nevertheless, taken in conjunction with the TABLE II. — Showing the Relative Number of Strongtli in Healthy Birds and in those believed to be suffering from "Grouse Disease " Birds received alive, apparently in good liealth, or sent as average apecimens of normal Grouse. Diseased birds picked up dead. Grouse No. Number of Strongyli. Grouse No. Number of Strongyli. 81 53 2,506 52 79 2,556 48 32 74 3,114 43 45 78 3,340 58 113 74(a) 3,406 59 235 80 3,840 46 259 75 4,352 60 290 39 6,230 49 330 71 7,058 47 344 73 7,484 55 415 77 8,800 63 533 72 10,266 51 540 76 18,332 64 571 57 599 62 730 69 730* 67 833 44 871 66 945 54 1,645 56 1,868 70 2,524* 60 6,995t 61 9,562t * One csBoum only counted and the numbers doubled, t These birds came from the same moor. changes hereafter described in the mucous membrane of the caecum, and the relation of the worms thereto, it is exceedingly probable that the worms are really the cause of the disease. It is to be noted that the maximum incidence of infection is strictly seasonal, for though in isolated cases or in isolated GROUSE DISEASE "—STRONGYLOSIS 211 outbreaks birds may die from Strongylosis, even in late autumn, both sexes die in April and May in very much greater numbers TABLE III. — Showing the Seasonal Prevalence of the Principal Grouse Entozoa. Appakentlt Hbalthy Birds. Hand-reared, shot, or caught by keepers as examples of healthy birds. Date. Hymenolepis. Davainea. Strongylus. Feb. 3, 1909 1 1,645 n 7 415 5 5 1,868 11 599 113 6 235 Mar. 17 Few Numerous 5,995 5) Numerous )) 9,562 19 730 20 Numerous 533 J) )} Many 571 1, 2 183 1 945 30 ,, Moderate 833 April 22 Few 877 27 Numerous Numerous 730* a )» >> 2,524* May 7, 1908 June 3,1909 Few July 10, 1908 Few 1 Few V. 28 Few Aug. 5, 1908 10 2 Numerous 15 Numerous Numerous 18 1 26 Numerous 30 Few Numerous Few Numerous Few Numerous 30 Moderate Moderate Moderate Numerous Numerous Few Few Moderate Sept. 2' 1908 6 Got. 23, 1908 Numerous Numerous 28 Few Deo. 8, 1908 1 45 871 ■9 259 344 32 Several 330 290 540 17,' 1909 21, 1908 * The Strongyli in one ceecum counted and number fonnd doubled. 212 THE GROUSE IN HEALTH AND IN DISEASE than in any other months of the year. This fact is brought out in Tables III. and IV., from which it will be seen that while twenty birds are reported to have been diseased in April and May only five are shown during the remainder of the year. TABLE IV. — Showing the Seasonal Pebvalbnce op the Principal Gkouse Entozoa. Appear- ance of unhealthy caeca. Diseased Birds. Picked up dead on the moors or caught in a weak condition. Date. Hymenolepis. Davainea. Strongylus. May 10, 1909 Numerous 7,058 if 1) Numerous 10,266* 5, 1908 9) Numerous J» Numerous Few }} 91 Numerous " y, 1908 99 >> J, „ 1909 99 Fragments 7,484 9, 1908 ■ >t Numerous Numerous )1 ») 91 91 i» 9J 19 Numerous >9 99 19 19, 1909 Moderate 3,ii4» ji Numerous 3,406 » t9 Numerous 4,352 1) )) 18,332* Numerous 8,800 24, 1909 »» Few 3,340 June S, 1909 Few 2,556 11 3,840 Aug. 26, 1908 Numerous 30 Numerous Numerous Numerous Oct. 23, 1908 Few Many 6,230 28 Moderate Numerous Moderate Numerous * Tiie Strongyli in one caecum counted and number found doubled. The serious injuries caused by the presence of T. pergracilis in the caeca, the accompanying symptoms and the general pathology may now be referred to. When the caecum of an infected Grouse is examined it will be found to show certain well-marked appearances. Instead of an intestine of a brownish or greenish grey colour moderately filled with soft brown pasty material, and showing greyish yellow lines running down its length on the outside "GROUSE DISEASE"— STRONGYLOSIS 213 indicating the eight or nine long villous ridges within, the csecum of a diseased bird becomes a distended tube with over- full and congested blood-vessels ramifying over it on the out- side, standing out very often in conspicuous contrast with a yellowish fatty-looking gut-wall ; or the whole substance of the wall of the csecum may be congested to a deeper tone, and may look dark, blue-black, and unhealthy. Before opening the gut, the congestion of the mesenteric vessels is the most conspicuous point. This is due to a venous congestion, and it means that the liver and other abdominal viscera and the right side of the heart are overfull. The liver may be very dark. It decomposes rapidly, becoming of a black, tarry, soft and very rotten consistency ; but this is not a safe indication of disease. The difference in appearance between a healthy liver during decomposition and a diseased liver is so uncertain that, after a day or two of summer heat, it becomes impossible to judge whether the bird was diseased or not. The right side of the heart is often enormously distended with black blood in a bird that has died of disease. This condition of the heart, however, must not be taken as necessarily present whenever the csecum is diseased. When the caeca of a large number of Grouse, all suffering more or less from Strongylosis, are opened up and examined in various stages of freshness, and in some cases after a lapse of many days since death took place, the appearances are very variable. In some birds the upper portions of the cseca are almost' transparent, but this transparency is certainly increased by the post-mortem decay of the mucosa. The longitudinal ridges, moreover, gradually diminish in breadth as the blind end is approached. The thickenings so conspicuous in some birds are far more abundant at and towards the open end. The ridges are sometimes very obviously alternately large and small, giving four broad and thick and four narrow and thin. In bad cases the villi are intensely congested, and in a certain number of cases there is evidence of internal bleeding having 214 THE GROUSE IN HEALTH AND IN DISEASE Tricho- strongylus in healthy birds. Signs of Strongy- losis. taken place here and there. But extensive bleeding does not occur in Strongylosis, or at any rate no indication of it has been seen in any bird dissected. The reasons which lead to the belief that there is always a loss of blood as a chronic symptom in this disease are that the congestion is always present, and is often excessive ; that a small amount of bleeding has been seen, and that in some advanced cases there is every appearance of anaemia or bloodlessness. In some birds the pale, bloodless, fatty and degenerated aspect of the tissues of the internal organs was most suggestive of anaemia, and of chronic blood poisoning. It is possible to find quite a number of very healthy looking birds of good weight and yet with a large number of Trichostron- gylus and a considerable amount of villous reddening. This is not surprising in such a disease as Strongylosis, which is essentially a progressive ailment. Everything depends upon the strength of the bird, and its power of resistance. There is no doubt that some birds will retain their weight and continue for some time in apparently perfect health, with a very great number of Trichostrongylus in the caeca, and a considerable amount of congestion. There is also little doubt that an observer may be easily misled by a normal redness of the caecal lining due to ordinary processes of digestion. This is especially the case if the bird examined happens to have been in the middle of this process at the moment of death, and if death occurs without loss of blood. The digestive organs must all be more full of blood at that time than at others, though in a bird like the Grouse which eats all day long, the difference may be less marked than it would be in ourselves or in birds of prey which feed at intervals. The chief signs of a bad case of Strongylosis so far as the caecum is concerned are : — (1) An excessive number of the worms, which can be seen stringing across between the lining membrane and the caked contents of the gut, if the contents are fairly dry. If the contents are moist by taking a small quantity of the gut "GROUSE DISEASE "—STRONGYLOSIS 215 contents and squeezing this flat between two glass slides, the worms can be easily seen as transparent threads when held up to the light. Innumerable ova of the worm also will be found lying loose in the csecal contents, (2) The longitudinal ridges of the caeca, eight or nine in number, are very much thickened, chiefly because the amount of blood held by them is excessive, and the lining becomes inflamed. (3) The swellings on the ridges which are conspicuous in a healthy bird as greyish nodules, are far more conspicuous in a case of Strongylosis when they become reddened and congested, and seem to suffer to a greater extent and earlier than the remainder of the ridges and the rest of the caecum. In some cases, however, the time comes when every villus in the whole gut seems to be intensely red and congested from one end to the other. (4) There may be a very great deal of thickening of the lining membrane from the swelling up of the villi and, after post-mortem decay, the caecal membrane seen in water may have the appearance of a furry rug. The contents of such caeca are sometimes obviously blood-stained, and there seems to be a bleeding form of the disease which results from the sudden access to the gut of a very great number of young worms all in a fully metamorphosed state. Such a case was produced experimentally, and bleeding occurred in the caeca. There is no apparent reason why under certain easily imagined circum- stances the same thing might not happen in early spring-time under natural conditions. (5) There may be appearances of recovery. In a good many birds the caecal lining is dotted all over with minute black pigment granules, in other words some of the villi show no blood-vessels injected, but are filled with pigment granules instead. These are sometimes so abundant as to colour the gut. They lie in the villi in great numbers. It is possible that they result from previous chronic congestion, and that there are circumstances under which 216 THE GROUSE IN HEALTH AND IN DISEASE the bird may rid itself of an excessive number of Tricho- strongyltis. This supposed recovery from Strongylosis may have resulted from some unknown vermifuge herb or from improved conditions of life. The worms, one must suppose, remain in the gut ; but the congestion is overcome, and the bird is not very much the worse for their presence. But, if the congestion is allowed to continue and become chronic, the digestion and absorption of food must go from bad to worse, and with it every other function of the body. Nothing will prevent the bird in this case from losing weight, and eventually its life. As for the exact cause of the congestion, it may be due to mechanical constriction of the filaments of the villi by the nematode worms. Each time the gut contracts peristaltically the worms have to hold on tightly to the gut lining to avoid being dislodged with the dejecta, and the result is seen in sections where the villi are evidently mixed up inextricably with the coils of Trichostrongylus. Or the congestion may be due to the chemical irritation of some poison produced in the gut by the worms, or by the defective digestion of food stuffs, or by bacteria living in the gut in its unwholesome state. Alter- natively it may be due to some or all of these conditions together. On the whole the mechanical view seems the most probable. The peristalsis is acting in a way to dislodge the worm, and the Trichostrongyliis has no other way of retaining its position in the caeca save by coiling round something, and the peristaltic action of the caecum must be fairly strong in comparison with the strength of the worm, for the free end of the worm has to be released at every wave of peristalsis from immersion in a thick, pasty material which is being driven outwards at each contraction of the gut. It thus seems evident that the small and delicate processes of the villi may be continually on the stretch, at first looped round tightly by a worm, the coil may then relax, blood may enter the capillaries, only to be compressed anew and so on, conditions which cannot but produce irritation "GROUSE DISEASE "—STRONGYLOSIS 217 and congestion on a large scale if multiplied a sufficient number of times. Apart from the appearances in the caecum there are several ^^? 9* other indications of this form of disease. The most reliable, and certainly the most easUy recognised, is that of loss of flesh and weight. It is for this reason that the average weight of the birds on a moor is the best indication of the prospect of health or disease in the near future. The tradition, for it is probably no more than a tradition, that in some outbreaks of " Grouse Disease " birds have been found dying or dead in plump condition and of normal weight, is discussed elsewhere. No such case has been observed during the course of the recent Inquiry. Grouse do not die of Stron- gylosis without loss of weight, and the reason is not far to seek when an infected bird is dissected. Strongylosis does not appear to have a very marked effect upon the temperatiu:e. The average body temperature of a Grouse in full health is 106"42° F., but when suffering from Strongylosis this temperature tends to fall. The average temperature of birds infected with Strongylosis was found to be about 105"07° F., but the number of cases observed was not large, and the question requires fuller investigation. In view of the opinion expressed by Professor Klein and Strongjrlosis others that " Grouse Disease " is due to an infection with bacteria, more especially with bacilli of the " coli " group, the Committee made careful observations as to the relation between Bacillvis coli in the organs and Strongyles in the cseca. At an early stage of the Inquiry it seemed probable that some such relation existed, for in birds reared in captivity, and thus kept entirely free of Strongyles, the organs contained no bacilli of the coli type (one exception). On the other hand, in the organs of Grouse with very large numbers of Strongyles, Bacillus coli was constantly present, either in the liver or some other organ. In other Grouse with fewer Strongyles, Bacillus coli was present in some and appeared to be 218 THE GROUSE IN HEALTH AND IN DISEASE absent in others. The results may be given in the form of a table. TABLE V. — Showing the Relation between the Ntjmbeb of Steongtles IN the CiECA AND BACILLUS COLI AND BACILLUS ENTEBITIDIS IN THE OTHER Organs. Cultures from Organs. Grouse No. Number of Strongyles. Liver. Lungs. Spleen. Kidneys. 52 81 48 32 43 45 58 113 59 235 B. coli 46 259 B. coli 50 290 B. coli B. coli B. coli 49 330 47 344 B. ent. B. ent. 55 415 63 533 51 540 B. coli B. ent. B. ent. B. ent. 64 571 57 599 B. coli 62 730 B. coli 67 833 44 871 B. coli 66 945 54 1,645 B. coli B. coli 56 1,868 B. coli B. coli 60 5,995 B. coli "6" 61 9,562 B. coli The points which come out clearly from this table and from other observations are : (1) that when Strongyles are absent from the caeca or are present only in small numbers (less than a hundred), intestinal bacteria, especially Bacillus coli, are not present in the liver or other organs of the Grouse (eleven Grouse — one exception); (2) that when a moderate number of Strongyles are present (one hundred to one thousand), Bacillus coli may or may not be present in the organs (twenty-one Grouse) ; and (3) that when great numbers (over one thousand) are present. Bacillus coli has invariably been found in the liver or other organs (twenty Grouse.) "GROUSE DISEASE "—STRONGYLOSIS 219 Having ascertained that a relation exists between the numbers of Strongyles and the presence of B. coli in the organs it became necessary to discover whether a similar relation exists between B. coli and the other intestinal parasites commonly found in the Grouse. The tables of results are given in the original Report, but it is only necessary here to state (1) That the presence of the tapeworm Davainea urogalli in the intestine is not related to the presence of Bacillus coli in the liver and other organs ; (2) That the presence of the tapeworm Hymeno- lepis microps in the duodenum is occasionally related to the presence of Bacillus coli in the liver and other organs.^ It has been shown that Bacillus coli is constantly present in the organs of birds whose cseca contain large numbers of Strongyles, and that the latter are present in far larger numbers in diseased than in healthy birds. It may therefore be assumed that Bacillus coli, while not invariably absent from the organs of the apparently healthy bird, is constantly present in those of diseased birds. The small number of colonies of Bacillus coli cultivated from the tissues of diseased Grouse indicates that these bacteria do not multiply in the tissues. We therefore do not suggest that " Grouse Disease " is essentially an infection with these bacteria. It is very doubtful whether the bacilli which find their way into the organs do much harm. Some harm no doubt they do, but how much cannot be said. Microscopic examination has not revealed any profound changes in the livers of Grouse. The numbers of these bacteria which penetrate into the organs is difficult to estimate because, doubtless, they soon get killed in the living tissues, so that the numbers of colonies cultivated must bear only a small proportion to the total number of bacteria which have entered the fragment of tissue examined. The number of living bacilli in the organs of these Grouse is undoubtedly small from which it is evident that they do not multiply in the organs. " Grouse Disease " is therefore not an infection with these bacteria. Is it a form of blood poisoning {toxoemia) caused 1 Vide, p. 200. 220 THE GROUSE IN HEALTH AND IN DISEASE by the poison liberated from bacteria which have been absorbed from the intestine, and which have almost immediately perished in the tissue ? We know that in order to produce serious mischief in animals by a single injection of dead bacteria a considerable quantity must be employed ; and it is difficult to believe, when we remember the small number of colonies which grew on the cultures, that relatively to this quantity the numbers of bacteria absorbed could have been very large. On the other hand, there is little information concerning the influence of the constant absorption of small numbers of bacteria, but this is believed by Adami and his school to be a potent source of disease. The fact that Bacillus coli has been repeatedly found in the livers of " normal " birds, badly infected with Strongyles, prevents us from ascribing the death of the Grouse directly to these bacilli, though they probably play some part. If these are really numerous, their products will doubtless exert some amount of harmful influence, but how much we are not at present in a position to say. The fact that no important lesions have been found either by macroscopic or microscopic examina- tion in the livers which have yielded cultures justify the view that the bacilli play only a secondary part in the causation of death. From the foregoing remarks it will be seen that the case against the nematode, or round worm Trichostrongylus pergradlis, is fairly clearly established, for though this parasite is seldom entirely absent from healthy birds, its presence in large numbers in the caecum is usually associated with definite lesions. Tricho- strongylus probably does little harm if not present in too great numbers. With regard to the presence of the worm in large numbers in some of the birds caught on the moor, and supposed to be healthy birds, it must be remembered that strong wild Grouse are difficult to catch, and that some at least of the methods of capturing Grouse alive seem calculated to catch the weaker birds rather than the stronger ones. On the other hand, on counting the Strongyles in a number of " normal " and diseased birds, there has been found a great difference between the two classes, very large numbers being always found "GROUSE DISEASE "—STRONGYLOSIS 221 in the diseased birds, much larger indeed than those found in all but the exceptional members of the healthy class, and these, for reasons just stated, may perhaps not be normal at all but suffering from the early stages of " Grouse Disease." These nematodes, in birds picked up dead or sent for examina- tion as suffering from " Grouse Disease," are almost always associated with grave changes in the lining membrane of the caecimi. Concurrently with these changes intestinal bacteria, particularly those belonging to the Bacillus coli group, find their way into the liver, or even into other organs, but no direct injury can be traced to the presence of these intestinal bacteria. " Grouse Disease," then, does not appear to be a specific bacterial infection. It would seem that all the birds which are more or less severely affected by Strongyles suffer direct injury to the caeca to an extent which is more or less proportional to the severity of the infection. Some exceptionally strong birds may stand a larger infection better than weaker birds will stand a lesser ; but, on the whole, the birds with the largest numbers of Strongyles suffer most. Their nutrition is impaired owing to interference with the normal absorption of digested food, and to the abnormal absorption of soluble poisons and intestinal bacteria. Such birds become the weakest ; and when food is scarce, as it is at the beginning of spring, especially after bad winters or on overstocked moors, or when other harmful influences prevail, it is the weakest birds which suffer most. They die of Strongylosis acting on a constitution already weakened by the consequences of privation, while their stronger neighbours manage to pick up a living somehow, and so tide over the period of distress. Part II. — Life History of Tricmostrongylus pergragilis In view of conclusive evidence accumulated by the Inquiry regarding the constant presence of the Trichostrongyltis pergracilis in the caeca of nearly all sick adult Grouse, it became a matter of importance to study in some detail the life - history of this 222 THE GROUSE IN HEALTH AND IN DISEASE Develop- ment within body of the Grouse. parasite with a view to determining the manner in which it is reproduced and disseminated, the mode of infection of healthy birds and, if possible, to obtain experimentally the symptoms of " Grouse Disease " under artificial conditions. In order also to have some reasonable basis of fact upon which to establish preventive and curative measures, a knowledge of the conditions favourable to and inimical to the growth of the parasite at its various stages of development became necessary. The sexually mature females give rise to their progeny as eggs, which undergo a certain degree of development while still within the body of the worm. By the time they are laid the egg content has become subdivided into a large number of cells, forming what is technically known as the morula (Fig. 20). As morulce these eggs pass into and mix with the contents of the cseca of the Grouse, all further develop- ment thereupon ceasing. This suspension of development appears to depend upon a lack of some necessary stimulant in the csecal contents, for the eggs may be found alive and at the same stage not only several days, but even so long as a month after the death of the bird. In nature the caeca are evacuated periodically, and the ova thus pass out of the body with the soft portion of the bird's dropping. In one or two cases where a portion of the csecal contents had passed into the rectum, and had there become diluted somewhat by the fluid from the large intestine, eggs were found to have progressed to the formation of an embryo while within the body of a dead bird ; but such a condition is obviously abnormal, and does not invalidate the general conclusion that the eggs of this parasite require to pass out of the body of the bird before they are able to continue their growth, and that, in con- sequence, the parasites within the body cannot increase in number by sexual multiplication. Each and every parasite Fig. 20. Morula stage of egg. "GROUSE DISEASE "—STRONGYLOSIS 223 found within the body of the Grouse must therefore have actually entered it from the outside. We shall see later that this explains the apparent anomaly that whereas practically all Grouse are infected with Trichostrongylus only some suffer from the disease. The egg, when newly passed, measures 0-075 mm. by 0-046 mm. and contains a morula, composed of about sixty-four cells. If a freshly passed caecal dropping be isolated and kept Develop- uncontaminated no further development will take place in the egg outside ova contained in it. A fungus will gradually grow upon it, *^® ^^y- and owing to this and bacterial contamination the eggs eventually die. If the dropping be exposed to the drying influence of sun and wind, as on the moors during summer, it becomes caked and dry, and the eggs die. If, on the other hand, a csecal dropping be spread out in such a way as to admit of the whole becoming oxygenated by the atmosphere, and it be also slightly moistened, development will proceed, its rapidity increasing with the temperature. For the experimental study of the extra-corporeal develop- Cultural ment the following method was found most reliable. Petri *° dishes, as used in bacteriological research, of a diameter of about 4 inches, were employed in pairs. Into the upper dish was placed a closely fitting piece of thick blotting paper, which was thoroughly moistened with water. The inside of the lower dish was smeared uniformly with a very thin layer of caecal dropping or csecal content taken direct from a dead bird. Several drops of water were then added and mixed into the viscid layer by means of a glass microscopical slide so as to produce a glairy mixture that would but slowly slide oft the Petri dish when it was held almost upright. The layer of faeces should be sufficiently thin to allow of an examination under the microscope with a two-thirds inch lens. The upper Petri dish was then placed over the lower dish, forming a close chamber, the atmosphere of which quickly became saturated with water vapour. From time to time the Petri dish was opened and a small quantity of faeces removed on a platinum wire for 224 THE GROUSE IN HEALTH AND IN DISEASE Develop- meutal changes in ovum. microscopical examination, or the lower part was placed upon the stage of the microscope and directly observed. A similar method, and one which permitted the study of the various stages of development in a small number of eggs, was the use of hanging drop dishes. If the former of these two methods has been adopted, in the course of twelve hours the colour of the culture in the Petri dishes should have changed from a greenish yellow to a reddish brown, and a sickly sweetish odour, similar to that found in lactic acid fermentation, should have become distinctly appreci- able. Otherwise experience teaches that putrefactive processes will almost certainly set in and lead to the destruction of the eggs and worms in the culture. After the eggs have hatched, and when minute worms are seen wriggling through the culture, it will be found advantageous to leave the Petri dish open for several hours in order to allow of the evapora- tion of some of the water, so that the culture acquires more consistency. A larger amount of water appears to be necessary for the growth of the young parasite previous to hatching than after- wards. Indeed we shall see later that a certain amount of consistence in the medium appears to be absolutely necessary for the full growth of the young worm. In the culture made by the above method the egg mass continues rapidly to segment until the resulting cells are exceed- ingly small. The mass becomes somewhat flattened, and a slight dimple appears at one border of the oval disc (Fig. 21). This is the first step towards the formation of the cylindrical body of the young embryo. By the gradual deepening of this dimple the egg mass acquires a tadpole-like appearance, the anterior end being, thus early, easily distinguished from the posterior end of the body. The anterior portion soon exhibits a central depression, which indicates the commencing forma- tion of the mouth (Fig. 22). As the lateral dimple continues to deepen the body mass elongates to such an extent as to become folded upon itself two or three times, in order to become " GROUSE DISEASE "—STRONGYLOSIS 225 accommodated within the shell (Fig. 23), The alimentary canal meanwhile has gradually been developing, so that by the time the embyro attains a cylindrical form the canal is found to extend throughout the body as a distinct cell- walled tube (Figs. 24, 25). During the whole of this period the embryo remains quiescent, but about an hour or so before Fig. 21. Fig. 22. it leaves the egg-shell Developing ova of T. pergracilis. it commences to exhibit a certain amount of movement. This movement gradually increases in extent and vigour, until it ultimately overtaxes the resistance of the egg shell, which Fig. 23. Fig. 24. Formation of the larva of T, pergracilis. Fig. 25. suddenly ruptures. The success or failure of these efforts on the part of the young worm appears to depend on the amount of water which is imbibed from the outside, for if only such an amount of water be added to the culture as is absolutely necessary p 226 THE GROUSE IN HEALTH AND IN DISEASE to set the process of development in motion, and the culture be then allowed to dry somewhat, it will be found that the embryo is incapable of rupturing the egg shell. A slight collapse of the egg shell, owing to an insufficiency of water, causes the death of the embryo at any period of its growth. Hatching usually takes place from thirty-six to forty-eight hours after the egg passes out of the bird ; but in summer it may be delayed for even as long as a month. When the embryo is hatched there seems little purpose in its early movements. The cuticle, at first irregularly crinkled, gradually smoothens as the parasite becomes saturated with water. The movements now appear to gain in purpose, and very soon the little worm is actively moving about, obviously in search of food. Description When newly hatched, the embryo measures 0"36 mm. in embryo. length, and 0'15 mm. in greatest thickness (Figs. 26, 27). The body is cylindrical, tapering to a slender pointed tail in the last 0"1 of a mm. of its length. Anteriorly it maintains an almost uniform diameter to within 0*05 of the mouth, when it shows a slight and gradual narrowing. The anterior extremity ends bluntly, and has a diameter of 0'0075 mm., presenting at its summit the small rounded opening of the mouth capsule. At 0*06 mm. from the tail the anal pore opens with but little external indication. Alimentary Canal. — Two faint parallel lines are seen running inwards for a distance of 0"01 mm. from the oral pore. These are the walls of a cylindrical mouth capsule, which later, with the growth of the worm, become much more thickened and obvious. Upon the success of the embryo in obtaining a plentiful supply of food depends almost wholly its future growth. If a -freshly hatched embryo be transferred to plain water it will live for several days, but show no growth or further develop- ment. Evidently there is only a sufficiency of reserve substance within the ovum to develop the embryo to the time of hatching. When there is enough food, but the medium is very liquid, GROUSE DISEASE "—STRONGYLOSIS 227 the worm requires to exert itself to a much greater extent in The first order to entrap small solid particles of food into its rigid mouth ecdysis. capsule. If, however, the ciilture is of such consistency that the embryo is able, by burrowing its way through the fsecal matter, to force this into its mouth capsule, there follows a very rapid growth in size even when there is a marked lack of oxygen. Under these favourable conditions of food supply an embryo increases in size to such an extent that on the fourth or fifth day from the com- mencement of the culture it is obliged to shed its cuti- cular covering. At this time thousands of very delicate sheaths may be found float-^ ing in the culture for a few hours ; but they very rapidly disappear. No important structural alterations accompany this first moult or ecdysis, but during the succeeding three or four days certain changes within the body of the worm gradually become evident. The cylindrical mouth capsule (Fig. 28) slowly loses its clear cut border and appears to be undergoing absorption, and its lumen decreases (Fig. 29). At the same time the oesophagus lengthens, the bulbous posterior portion becomes pyriform, and later merges into the anterior portion, but so gradually as to be only definable with difficulty. The cuticular lining of the whole oesophagus, and the marked triradiate lining of the Figs. 26 and 27. Newly hatched embryos of T. pergracilis, highly magnified. The meta- morphosis. 228 THE GROUSE IN HEALTH AND IN DISEASE oesophageal bulb (Fig. 29) become resolved into a simple thin cuticular covering (Figs. 30, 31). The walls of the intestine, which have gradually increased in size, become more clearly defined, and now appear as cylindrical turgid cells distended with large globules of highly retractile substance, giving the (I) Fig. Fia. 29. Fig. 30. Fia. Changes in T. pergracilis during ecdysis and encystment. 31. larva a characteristic appearance by which it can be readily distinguished from free-living nematodes (Fig. 30), The whole body appears to have slightly narrowed during the process of metamorphosis, by the conclusion of which the larva has become changed into a slender actively moving worm, with a simple elongated oesophagus without mouth capsule (Figs. 30, 81). Accompanying the metamorphosis in structure is a marked change in habits, for instead of burrowing into the "GROUSE DISEASE "—STRONGYLOSIS 229 denser portions of the food these metamorphosed forms now rush about with great rapidity, and either wriggle into the patches of open water or make their way on to the actual surface of the culture, and may be seen standing out in numbers into the moist atmosphere above, forming a kind of hoar frost on the surface of the faeces apparently in search of oxygen. Those larvae, which are fortunate enough to be near the edge of the culture, ascend in the condensed water on the sides of the Petri dish and make their way on to the upper part, eventually reaching the blotting paper. Others will crawl out of the thin edge of the culture medium and become stranded on the dry glass. This metamorphosis takes place between the eighth and sixteenth day from the commencement of the culture, the difference in time depending almost entirely on the tempera- ture at which the culture is kept. If the blotting paper be now removed, and the upper part The second of the Petri dish be put aside, so that the moisture on its inner "enoyst- surface, which contains the actively wriggling metamorphosed ™^'^*- larvae, be allowed to evaporate slowly, it will be noticed that as the water disappears the movements of the larvae gradually diminish and eventually entirely cease, so that ultimately the larvae lie, sometimes making irregular figures like notes of interrogation, sometimes coiled up like a watch spring (Fig. 33). If drying proceeds sufficiently slowly, it would be found on examining the dish with a hand lens that when all traces of moisture have disappeared the little coiled larvae stand out as turgid, glistening streaks. They seem to be capable in this condition of retaining a certain amount of moisture within their thick resistant cuticle for several days, and to make up for any loss of fluid by evaporation by slowly retracting the body from either end and of detaching themselves from their cuticular skin (Figs. 30, 31, 34). This retraction may go on to such an extent that if one suddenly adds water once more to a Petri dish containing such dried forms the little worms are found enclosed in long sheaths that extend much beyond each end, recalling the sheathed embryos of filaria seen occasionally in 230 THE GROUSE IN HEALTH AND IN DISEASE the blood of man (Fig. 34). This second formation of a sheath, or as it is sometimes called, the " encystment," is tjie last stage of the development of the larvae outside the body. It appears Fig. 32. As seen in water. Fi&. 33. As seen stranded on sides of dish. Larval forms of T. pergracilis. Fig. 34. Encysted larvse of T. pergracilis. Appearance on addition of water to forms shown in Fig. 33. to be a necessary preliminary to the attainment of infectivity, and once this stage is reached the larvae can remain alive without food or further growth for weeks. The larva does not shed this second sheath until it reaches the alimentary canal of the Grouse. There are thus two moults in the extra-corporeal "GROUSE DISEASE"— STRONGYLOSIS 231 development. The first is completed prior to metamorphosis while the larva is free-living ; the second, subsequent thereto, is not completed until after the larva has entered the bird. So much then for artificial experiments. The following details of an experiment made during August 1909 serve to illustrate what actually becomes of the hatched worms under natural conditions upon the moors. A culture made in the manner described above was taken to a small village, on the coast of the Bay of Cardigan, where no Grouse lived or had been known to exist for many years. Two or three small plants of hill heather were detached uninjured from crevices in rocks. These were planted in a Petri dish, and the dish was half filled with water so as to cover the roots. The plants were then set aside. A week later they were found to have survived the transplantation, and to have commenced to grow under the new conditions. As the weather was showery the plants and dishes were left out in the open, and for two or three days in succession the raindrops hanging from the tips of the heather were microscopically examined. They were found to be almost free of life. On one occasion, however, a small free -living nematode was found. Although slightly resembling the larvae of Trichostrongylus pergracilis it was readily distinguished from them by its microscopical characters. Immediately after one of these periodical examinations, the culture of Trichostrongyliis pergracilis, in which the majority of the larvae had just imdergone metamorphosis, was poured into the water round the roots of one of the experimental plants. The plant was left out in a typical " Scotch mist " for a couple of hours. At the end of that time raindrops were again taken from the highest tips of the heather, which were about 3| inches above the surface of the water, and they were found to be liter- ally swarming with the actively wriggling metamorphosed larvae of Trichostrongylus pergracilis. These larvae had ascended the wet stems and leaves of heather against the current of water that was trickling down towards the roots. Their intense activity was doubtless due to the large amount of oxygen 232 THE GROUSE IN HEALTH AND IN DISEASE present in the fresh rain. The plant was then taken from the Petri dish and placed in a cardboard box, which was sealed down. A month later the box was opened. The heather was found to be alive still and growing, but very dry. The tips of the shoots from which the raindrops had been taken were cut off and soaked in little watch glasses of fresh water, and in the course of half an hour there wriggled out from the crevices of the leaves of the heather a considerable number of larvae, showing at either end the long collapsed parts of the sheath which as we have already seen are characteristic of the larvae that have undergone drying under artificial conditions. The intestine showed the characteristic refractile appearance already noted. The following synopsis of the life history of this parasite may be of interest as summarising the order and minimal duration of the various stages in the life-cycle. April 1. Egg in morula stage passes out of Grouse in soft dropping. „ 3. Larva hatches out and lives in dropping of Grouse or in moist earth. „ 5. First moult or ecdysis. „ 8. Metamorphosis, larva now in actively migrating form. „ 9. (or after). Larva ascends to tips of heather ; if there is no mist, rain, or dew the ascent will be postponed. „ 10. (or after). Encystment or drying ; this represents the first stage of the second moult — an indefinite interval may intervene here. „ 10. Larva swallowed by Grouse, and completes second moult. „ 11. Reaches caeca of Grouse. „ 13. Completes the hypothetical third and fourth moults, thereafter become adult and sexually productive. » 13. Pairs as soon as adult stage is reached. "GROUSE DISEASE"— STRONGYLOSIS 233 April 14. Lays eggs in caeca. „ 15. Eggs pass out of Grouse. Thus the exact mode by which the worms attain to the most favourable conditions for infecting the Grouse had been deter- mined, for the young growing tips of heather are those most sought after by the birds. It remained to be seen whether the adminis- tration of these metamorphosed encysted larvae to healthy Grouse would result in the actual production of Strongylosis. It had been found that the administration of eggs and Experi- embryos of the Trichostrongylus pergracilis and of centrifugalised Eduction washings of heather from the moors to healthy uninfected pfStrongy- ° •' losis. Grouse had given uniformly negative results. From the observations described above the explanation of these failures becomes evident. The eggs and embryos of the parasite require to undergo certain essential developmental changes for a period of almost a fortnight's duration before they acquire the power of infection when swallowed by Grouse. Even the administration of larvae was at first inconclusive, for the larvae obtained from the heather in the earlier experiments were undoubtedly those of non-parasitic nematodes, the young of which bear a general resemblance to the unmetamorphosed embryos of Trichostrongylus pergracilis — many of them having a very similar type of mouth capsule. Moreover, the embryos of Trichostrongylus pergracilis do not acquire their migratory habit until they have become metamorphosed, and therefore do not ascend the heather until they have entirely lost their oral capsule. Until the above described experiments were successfully concluded the characters of the metamorphosed larvae were quite unknown, and therefore it was impossible that they should have been recognised in washings of heather. The administration of the metamorphosed larvae was carried out at the Committee's experimental station at Frimley in Surrey. On June 19th, 1909, a culture of larvae which had just undergone metamorphosis, and which were therefore in the active migrating stage, was administered to an adult male bird 234 THE GROUSE IN HEALTH AND IN DISEASE one year old. The droppings of this bird were entirely free from Trichostrongylus ova when the experiment was begun, and^there- f ore the bird was entirely free from all suspicion of prior infection. An examination of the faeces on the successive days showed that no infection had taken place. By June 26th the culture had undergone further developmental changes, and showed a large number of "encysted" forms. A dose was again administered and some four days later ova of Trichostrongylus pergracilis were found in the droppings. The number of ova increased on successive days. On July 3rd a further dose of the same culture, now thirty days old, was administered. The bird died five days later, showing distinct loss in weight, the presence of a large quantity of chalky fluid in the rectum, and the csecal contents red with blood. From the post-mortem examination the conclusion was formed that the bird had been killed by the passage of some of the last culture into the lungs, for there were obvious signs of pneumonia, and quantities of the culture were found in the fine tubules. This first experiment was therefore not wholly conclusive as regards the actual induction of Strongylosis by the administration of encysted metamorphosed Trichostrongylus pergracilis larvae. It served to establish, however, that these larvae can reach the caeca of the Grouse, attain their adult condition, and become sexually productive in the very short space of four days. It also demonstrated that the sudden invasion of the caeca by a large number of Trichostrongylus pergracilis produced so marked an effect upon the mucous membrane as to fill the caeca with blood. In the second experiment the culture was much older, and contained encysted forms. The doses were repeated periodically, with the result that in the course of two and a half months the bird fell in weight from 17 ounces to llf ounces. The caecal droppings were as full of Trichostrongylus pergracilis ova as those of a bird suffering from Strongylosis, and the bird itself showed a similar condition of progressive weakness and emaciation. The mucous membrane of the caeca was "GROUSE DISEASE "—STRONGYLOSIS 235 covered with Trichostrongyltis pergradlis, but no evidence of extravasation of blood into the lumen of the cseca was found on the death of the bird. Apparently that seen in the first case must have been associated in some way with the develop- ment of the parasite before reaching maturity. These two experiments indicate in so far as such a limited number may, that this parasite in very large numbers has a marked pathogenic action upon Grouse, inducing loss of weight, progressive wasting, and in extreme cases, death. If it be accepted that Trichostrongyliis pergradlis is the Remedial primary and essential factor in the production of the common ™®^s"''^8- form of " Grouse Disease " remedial measures must be directed either to the destruction of the adult parasite within the bodies of the birds, or of the young forms during their stay outside the body. The impracticability of the former of these two methods is obvious. The birds are unapproachable, and are spread over a very wide area. Vermifuges or antihelminthics are expensive and more or less poisonous substances, the dosage of which has to be carefidly estimated and controlled. The problem therefore resolves itself into that of destroying the eggs and larvae of the parasites during their existence outside the body of the bird. The destruction of the eggs or embryos by surface dressing with cheap chemical substances would appear at first sight to be a hopeful line of action, but the occurrence of the csecal droppings more or less all over the moor, and the enormous area requiring treatment, render the suggestion of any such method futile. Moreover, as we have shown, the larvae after a brief period of development ascend the heather and can remain hidden in the crevices of the leaves, in a quiescent, invisible, and living state for a prolonged period. The only conditions that coxild be inimical to these — the infective forms — ^would be atmospheric conditions of marked severity, possibly a prolonged frost or a prolonged drought, or destruction of the infected heather by fire or cutting. The effect of extreme 236 THE GROUSE IN HEALTH AND IN DIST^ASE cold has been tested by subjecting the metamorphosed larvae to freezing in the cold storage rooms at the Albert Dock for a period of a week. On being thawed out of the solid block of ice they were found quickly to regain their activity. Exposure to slow drying, on the other hand, under experimental con- ditions, results in the death of the encysted larvae. Death from lack of moisture must be continually taking place on the moors, although there may often be, even at the hottest parts of the day, an insensible transpiration from the growing plant, sufficient to maintain the life of the larvae by preventing desiccation. Burning and cutting appear to be the only practical means by which infected heather plants can be properly purged. To any one unaccustomed to the moors it is a matter of astonishment to notice what might be described as the extraordinary insanitary condition of the Grouse's home. Nearly every square yard of moorland shows traces of faecal deposits, and this fact when once appreciated forcibly directs attention to the unnatural over-population of the moors. When one remembers that practically all Grouse are infected with Trichostrongylus pergracilis, and that from every dropping thousands of potential parasites normally emerge, it becomes evident that the greater the number of birds upon a given area the greater in turn must be the infecting capacity of the moor. But on most moors only a very small proportion of the heather is suitable for food for Grouse at certain times of the year,i and as the Grouse is a very heavy feeder it follows that the parts of the moor from which the food supply is derived are just those likely to be the most heavily contaminated with droppings. The number of birds on a moor should be correlated, not with the size of the moor but with the extent of the suitable food area thereon. The amount of stock on a large moor may seem low proportionately to the whole area, but when estimated m proportion to the food area it may prove exceptionally high, and this means a high potential capacity for the production of Strongylosis, whilst the entrance of a few bacteria or ' Fide ohap. xii. pp. 351 et seq. "GROUSE DISEASE "—STRONGYLOSIS 237 protozoan parasites into the body may suffice to cause serious diseases owing to the rapid multiplication of the original germs. In helminthic infections, as we have shown, the parasite does not multiply inside the bird. Birds with few worms remain healthy. The progress of the disease is correlated with the actual number of parasites entering and surviving in the body. The more heavily infected the food, the more heavily infected does the bird become. The following facts connected with the growth of the parasite outside the body of the Grouse emerged from the Inquiry, viz. : — (1) that moisture is necessary for the development of the egg ; (2) that a minimal temperature of several degrees above freezing point is essential not only for the development of the egg, but also for the metamorphosis of the larva ; (3) that the larva ascends the heather only after metamorphosis ; (4) that the metamorphosed larvae are not killed by extreme cold ; (5) that they may be killed by extreme drought. These facts afford us some explanation of the disease being a fatal one in the spring months. During the summer months many of the csecal droppings must be dried by the sun and wind shortly after they are passed, and the eggs thereby killed. The same agencies must also desiccate beyond revival a large number of the encysted larvae upon the heather. During the winter months, however, this loss does not occur. Owing to the low temperature and continual wet the eggs remain in a living but quiescent condition. Even if an occasional spell of warmer weather occurs, and the eggs develop into embryos, it would be necessary that such period of high temperature should continue for at least a fortnight to enable these embryos to become converted into the active migrating larvae. The residt probably is that there accumulates upon the moors during the whole winter vast numbers of undeveloped eggs and unmetamorphosed embryos. The low temperature merely suspends their growth for the time being. At the spring-time the minimal temperature rises gradually to such a point as to allow the continuous develop- ment of the eggs and embryos to and throughout metamorphosis. The result is that at this period the accumulated result of 238 THE GROUSE IN HEALTH AND IN DISEASE faecal contamination during the winter months presumably ascends the heather. The frequent rains and mists at this time give the larvae ample opportunity to reach the topmost tips of the plant. The rapid death of the eggs of Trichostrongylus pergracilis in faeces that have undergone temporary drying indicates that the drier the moor, the more efficacious will wind and sun prove as natural antagonists to " Grouse Disease." Again, as the infective forms of the parasite occur on the " food " heather, it is evident that the greater the amount of " food " heather in proportion to each bird, the less likely it is to become infected. As the periodical burning of heather not only increases eventually the area of food heather, but at the same time destroys in the only effective way known the living parasites upon the area of heather burned, the policy of heather burning, advocated by the Committee upon other grounds, receives additional support. The practicability and value of a periodical cutting of the heather requires further consideration by those acquainted with local conditions ; but, if practicable, such a measure should not only be a means of ridding large areas of the moor of infective material, and of bringing about a rapid increase in the " food " heather area, but might also be applicable to those parts of a moor and in those seasons of the year when burning is impossible. Part III. — Incidence of Infection. It is necessary to emphasise the fact that Strongylosis is essentially a spring disease, for hitherto the view has been held that this form of Grouse Disease mortality occurs both in the spring and in the autumn with a break between. The mistake arises from incomplete observation of the facts. Owing to the natural objection to the disturbance of the moor m the breeding season the majority of gamekeepers make a pomt of never searching the ground for dead or sickly birds " GROUSE DISEASE "—STRONGYLOSIS 239 between the month of May when the early broods are hatched, and the end of July when the dogs are taken out to make a survey of the shooting prospects. Consequently, no diseased birds are found during that period even though they may be dying in hundreds, and by an optimistic method of reasoning it is assumed that because no disease is observed no disease exists. Conversely from the intimate knowledge of the moor TABLE VI SHEWfNG THE FALLACY OF THE AUTUMN OUTBREAK OF DISEASE Number JAN FEB MAR. APR. MAY JUNE JULY AUG. SEP OCT. NOV. DEC. 100 so eo 70 so so to 30 aa 10 (D) Number of Cock BIROS DEAD. -n /\ / \ f \ / / \, / \ -A A= 90 eo 70 eo so to so so to ' — ^ Number of COCK Biros SICK ONL Y / s /•^ / s / ^ / V / / N. / ^ so so 70 so 50 to 30 20 10 fD') HuMBEft Of HEM Biros DEAD -''*\ y^ — -_^ ■^, 30 BO 70 SO SO to SO 20 lO a. — ~~~ "■' (€') Number oe MEAi Biros SICK ONLY. A f\ ' \ , ^ / \ / \^ — s U^ — ; — — -, after August 12th, undue importance has been attached to this idea of autumn disease owing to a certain number of sickly birds being found in the August and September bags — ^birds which would otherwise have escaped notice altogether, but which were shot in the day's sport and afterwards picked out as " piners." The point is brought out in Table VI. which shows the number of dead or pining birds sent to the Committee for examination 240 THE GROUSE IN HEALTH AND IN DISEASE during a single year. It will be seen from Chart (D) that whereas no dead cocks were found in January, and very few in February and March, the number in April rose suddenly to over fifty, and in May to over eighty. This was followed by a sudden drop in June to less than ten birds, and from that time forward only occasional specimens were received. The fact that there was no increase in the number of victims in August when the moors once more came under observation, proves conclusively that mortality had practically come to an end by that date. It is probable that the sudden drop in the number of specimens shown for the month of June, would not have been quite so marked were it not for the practice, already mentioned, of avoiding all disturbance of the ground at this critical period. On turning to Chart (E) we find that few, if any, sick and pining birds were found in the first three months of the year, but that in April they begin to be noted, and in May the numbers rise to over fifty ; doubtless the numbers both in April and May might have been larger were it not that at a time when dead birds were to be found correspondents preferred to send them in preference to those which were merely sickly. It must also be remembered that a live bird is more difficult to catch than a dead one, and this fact doubtless accounts for more specimens being procured in May when presumably they had become weak, than in April when they were still strong enough to evade sus- picion and to elude capture. We may assume, therefore, that both in April and May the number of sick birds is very much larger than would appear from the specimens actually sent up for examination ; indeed, we may go so far as to say that the numbers of Grouse that die in an ordinary season is trivial compared to those that are sick and do not die. Once this point is established we have an answer to the question so frequently asked : " When once a Grouse is attacked by disease has he a chance of recovery, or is he doomed to succumb sooner or later ? " A further examination of the evidence furnished by the Charts aids us to an answer. Returning, then, to Chart (E) we find that in June and July "GROUSE DISEASE "—STRONGYLOSIS 24l practically no sick birds are found ; but here, again, we must not be misled, the moor is little visited in these months, and any infected birds there may be are now beginning to recover, and have so far shaken off the evil effects of the spring outbreak as to regain the power of flight. It is not until shooting commences in August that piners again begin to come into evidence ; birds that appear to be healthy and strong when on the wing are found when handled to be in poor condition. It is by no means a rare thing to find hens weighing 14 and Weight as 15 ounces still capable of flight. Often such birds are shot t^^^o^^"^' and afterwards picked out of the bag as " piners " to be examined disease. and condenmed as cases of disease. The appearances of ill-health are generally abundant. To begin with, the bird is undersized, the bones are found to be unusually small in their measurements and slight in their struc- ture, suggesting that the bird was bred late in the previous year. This gives it a bad beginning, and means that the bird, lacking strength, suffered more than the early bred birds during the previous winter months. If the bird is a hen, it will be evident from the naked skin of the abdomen, from the delayed moult of the feathers of the upper parts, and from the almost feather- less condition of the legs and feet, that a long and exhausting period of incubation has been endured, followed by a period of incessant watchfulness while the young brood required pro- tection. Often enough a hen " piner " in this condition appears to have suffered from no more definite disease than over-sitting* demonstrating that this is in itself a sufficient cause of extreme emaciation. Then, again, it may be found that the bird is overloaded with parasites. These, if the case is a true " piner," will be abundant within and without. The feathers are often alive with Nirmus and Goniodes, the small flat bird-lice, and the head of the bird may be dotted, especially round the eyes and ears, with ticks {Ixodes). The presence of Ornithomyia, the Grouse-fly, depends more upon the weather and season than on the condition of the host. Within, the duodenum will be occupied by a mass of Q 242 THE GkOtJSte IN HEALTH AND IN DtS^ASte Hymenolepis (tapeworms), or Trichosoma (threadworms), or both ; the main gut by a far more bulky mass of Davainea (tapeworms) ; and the caeca may be reddened from end to end by villous engorgement due to the irritating presence of thousands of Trichostrongylus (threadworms). In this state the bird is flushed and shot, and forwarded for a diagnosis. And still one more perplexing item, namely, that scattered here and there amidst thousands of Trichostrongylus ova, in the contents of the intestine, are encysted spores of coccidia, showing that the bird may have lost weight in the height of the summer by excessive Coccidiosis, and yet have survived. That these birds are recovering, and not dying, is proved by the fact that no fresh corpses are found, and gradually the piners become fewer as the period of convalescence proceeds, until in November and December there is not a sickly bird to be found on any moor. It follows that the common practice of ruthlessly killing down the stock in a disease year with a view to stamping out the disease is bad policy, for if the birds were allowed to live they would all recover their health before the end of the year. Turning now to the hens we find from Chart (D') that April and May are again the months of highest mortality. It is true that the death roll is not so heavy as in the case of the cocks, and this is quite in accordance with the experience of gamekeepers and naturalists by whom it is almost invariably observed that, in the spring, cock Grouse die from disease in a much larger proportion than hens. On the other hand, it is frequently noted that hens continue to die after the cocks have recovered their health, and this is confirmed by the Chart, which shows that the recovery of the hens is slower. The fact is still more clearly shown in Chart (E'), which shows that in August a very considerable proportion of hens are still suffer- ing severely from the after effects of the spring outbreak. The difference in the liability to sickness of the cock and hen respectively is almost certainly due to the difference in the conditions affecting each sex. "GROUSE DISEASE"— STRONGYLOSIS 243 It may be assumed that both cocks and hens have the same Power of opportunities for obtaining food, and that the quantity and quaUty of that food is thp same for each, consequently each will be equally liable to infection by the Strongyle worm. Why then do the cocks die in larger numbers than the hens ? Only one answer is possible, and that is, that whereas at this time the power of resistance of the cock is at its lowest, the power of resistance of the hen is at its highest. The fact is sufficiently proved by the comparison of the weights of the sexes, but if further confirmation be required it would be found in the fact that in June as the cock increases in weight so he becomes less liable to disease, whereas the hen, whose weight is on the downward grade, continues to suffer, and sometimes to die, throughout the summer months. The fact that the average weight of the cock is slightly on the upward grade during the months of greatest mortality is somewhat misleading, until it be remembered that he is still far below his best condition, and was probably about his worst at the time when he first contracted the infection. The reason why cocks do not die in September, nor hens in November, when their respective weights are again at their lowest, is obvious — ^mere loss of condition is not enough to cause death. It is only where this loss of condition is found in con- junction with a heavy infection of parasites that it becomes a source of serious danger. The reason why the cock bird should be improving in con- dition in June, while the hen bird should be falling off, has already been discussed,^ and it is only necessary here to repeat that in March and April the cock is subjected to the strain of breeding and moulting, and is recovering in May and June, whereas the hen does not begin to feel the corresponding strain until June and July. This probably also accounts for the fact that cocks die in larger numbers from^ " Grouse Disease " than hens, for at the time when the nematode infection is at its height the cock is more vulnerable than the hen. ' Fide chap. i. pp. S3 et seq. 244 THE GROUSE IN HEALTH AND IN DISEASE Relation Although healthy Grouse are at a much lower ebb, as disease and evidenced by their average weight, during certain months of weight. ^.j^g yg^j, ^^^^ during others. Strongylosis does not necessarily kill them off at these seasons. It kills oft the hens when they ought to be at their flood tide of health and vitality ; and the cocks when they ought to be on a good rising average tide. We have thus a paradox which may be stated in the following terms : — More hens die of Strongylosis during April and May than in any other month of the year, notwithstanding the fact that the healthy hen is then at her best so far as weight, fat, and plumage go. More cocks die of Strongylosis during April and May than in any other month of the year, notwithstanding that the healthy cock is then already recovering the weight which he lost during courtship, and is at a fair average and rising weight. And although one might expect cock birds to die in March and September, when the average weight is at its lowest, this does not occur. And whereas one might expect hen birds to die in June and July, or in November, when the average weight in health is at its lowest, this also does not occur. In attempting to explain this paradox, it is necessary to recapitulate shortly the conditions which lead to an over- infection of the Grouse with the larval Strongylus. Elsewhere it has been pointed out that, owing to the small proportion of heather which produces good food during the months of February, March, and AprU, all the birds upon a moor are forced to concentrate upon small areas of feeding ground.^ Consequently there is a tendency for these small areas to become heavily infected with Strongyles even from the droppings of healthy birds. At first there are no evil results, for the eggs take some, weeks to go through the necessary stages of metamorphosis without which they cannot become actively dangerous to the health of the bird.^ Thus, even by ^ Fide ohap. iii. p. 90. 2 yide p, 233. "GROUSE DISEASE "—STRONGYLOSIS 245 the end of February and beginning of March, there is com- paratively little mortality among Grouse.^ As time goes on, however, the infection becomes more and more intensified, for not only do the larval nematodes assume their most active form, but those which have been eaten by the Grouse at the beginning of the period have had time to produce eggs in the intestine of their host, and these eggs are in turn distributed over the moor to add to the infection. The unhealthy conditions do not result in immediate mortality — it has been shown by experiment that the birds which have been fatally infected may not die for many weeks.^ In some cases a severe infest- ment does not result in death.' Even in March the mortality has not reached its height,^ for the majority of birds fatally infected in March will probably not die till April. The infection of the ground goes on with growing intensity, and if the same conditions were prolonged for another month or two it is possible that on the majority of moors hardly a bird would survive. Fortunately the advent of spring brings a blessed relief to the plague-stricken stock, and with the first appearance of new heather growth at the end of April and beginning of May the risk of new infection is past. Thus it is that in April the infection reaches its climax, but the birds which die in April are probably the result of infection in March, whereas the birds infected in April die in May, even although the conditions have improved. 1 Vide Table VI., p. 239. ^ Vide p. 234. = Vide, p. 240. ■* VUe Table VI., p. 239. CHAPTER IX " GKOUSE DISEASE "—CONTmUED—COCClDTOSlS Refekence has already been made to the circumstance that in certain years there is a mysterious disappearance of the young birds even though the old birds appear to be healthy, and the weather conditions ideal. At first it appeared probable that this failure of the young stock was due to some climatic cause, such as wet or drought, or to the failure of some essential element in the food supply. As the subject was further investigated, however, it was seen that none of these explanations were satisfactory, and the matter remained in doubt until it was discovered that the mortality in question was the result of a definite disease which more particularly affected the young birds, and which had hitherto been overlooked. In the course of investigating Strongylosis in Grouse on the moors in May 1909, it was noticed that the cysts of a Coccidium — a minute animal parasite — often occurred in large numbers in the gut of Grouse chicks. These coccidian cysts are oval {see Fig. 35), and at first sight might easily be mistaken for eggs of worms, though they are somewhat smaller. The presence of the cysts was often associated with enteritis — in many cases with ki°Grouse^ fatal results. The discovery suggested that Coccidiosis was a chicks. factor in " Grouse Disease," especially in young birds. It is true that the occurrence of coccidian cysts had been observed in adult Grouse at various times, but not in large numbers, and there is no evidence that their presence in adult birds is attended with fatal results in any but exceptional cases. With a view to further investigation of this disease, Dr Fantham, in June 1909, spent some time upon a Grouse moor in Scotland, and the results of his researches there, and after- 246 GROUSE DISEASE"— COCCIDIOSIS 24T wards in the laboratory and experimental station, form the subject of the present chapter. The experimental results throughout have been carefully compared with those of natural Coccidiosis occurring in wild Groiise-chicks picked up on the moors each subsequent season. The Coccidium found in the gut of the young Grouse is known Text Fig. 35. Pigs. A-P. Stages in the development of the oocysts of Eimeria avium., as seen in fresh preparations. A. Cyst (more correctly ofa'oyst) with protoplasm completely filling it. B. Older oBoyst with contents forming a central sphere. Many such cysts are found in infected oeeoa and infected faeces of Grouse. C. Oocyst with four nuclei, ahout to form young spores. D. Oocyst with four round spore masses. E. Four ovoid spores (or sporocysts) within oocyst. F. Fully mature oocyst with four spores, each containing two sporozoites. The Coccidian oocysts are about one-hundredth the size of a small grain of wheat. to science as Eimeria {Coccidium) avium, and is a protozoal parasite invisible except under high powers of the microscope. Coccidiosis has long been known as a disease of rabbits, and is often fatal, but the species of Coccidium which attacks rabbits is different from that which affects Grouse, for Grouse chicks into which the Coccidium of the rabbit has been artificially 248 THE GROUSE IN HEALTH AND IN DISEASE Life history of the Coocidium. Sporozoites. Multipli- cative introduced, remain unharmed, and the cysts are merely passed out of the birds in their droppings. Occasionally Coccidiosis occurs as a disease in man. The species of Coccidium which infects Grouse is also capable of infecting fowls, pigeons, turkeys, pheasants, sparrows, and canaries ; indeed, it is probable that nearly all birds are liable to be attacked by this parasite. Amongst poultry farmers the disease is familiar under the name of " White Diarrhoea," one of the symptoms being the fluid condition of the excreta and the white colour given to them by the presence of millions of cysts — more correctly called oocysts of the Protozoon. In turkeys the disease is often known as " blackhead." The life history of the Coccidium is extremely complicated, even though, unlike some parasites, the organism completes its development within one host. Its life-cycle is fully described and illustrated in the first edition of the Committee's Report, and it will be sufficient here to give a brief summary of the changes through which the parasite passes during the period when it remains within the Grouse. Reference may be made to the text-figure on p. 248, which gives a diagrammatic repre- sentation of these changes. Beginning with the oocyst, which is swallowed by the Grouse with its food or water, we find that each ripe oocyst contains four sporocysts (Fig. 36, S) or spores, and each sporocyst contains two germs or sporozoites (Fig. 36, T). These germs are liberated by the action of the digestive juices (Fig. 36, A), and rapidly penetrate the delicate cells which form the lining of the gut (Fig. 36, B). In these cells the sporozoite rounds up (Fig. 36, C), and becomes a passive growing form or trophozoite (Fig. 36, D). After a period of rapid growth, during which time the trophozoite practically destroys the cell harbouring it, the parasite enters upon a multiplicative phase termed schizogony. The parasite at this stage is known as a schizont, The schizont is at first single (Fig. 36, D), but soon subdivides into a number of curved daughter forms arranged within the host- cell, like the segments of an orange (Fig. 36, E, F, G). These "GROUSE DISEASE "—COCCIDIOSIS 249 segments or daughter-germs are known as merozoites. The number of merozoites formed from a single schizont seems to vary ; eight to fourteen are common numbers, but as many as twenty have been found. The groups of merozoites now break up, and each free germ seeks out and enters an hitherto uninfected cell in the lining of the gut, and there each daughter-germ undergoes multiplication as before. Several generations of schizonts and merozoites are thus produced, each generation representing an enormous increase in the infection. When it is realised, that after passing through the multiplicative process four or five times, the original germ may be represented by many thousands of similar germs, it will be understood that they must exercise a very destructive effect upon the gut lining of the host, and this engenders the fatal illness in the young chick. Sooner or later a limit is reached, both to the power of the Grouse chick to provide nourishment for the parasite and to the multiplicative capacity of the parasite itself, and when the circumstances become thus unfavourable to further multi- plication, the parasite enters upon a new phase with a view to the perpetuation of its species, and produces forms capable of infecting fresh birds. The schizonts now cease to develop into groups of merozoites, Sexual but instead slowly give rise to male and female organisms. The female organism, containing much food-material, is known as a macro-gametocyte (Fig. 36, I, ? ), and eventually gives rise to a single macrogamete (Fig. 36, J, ?). The male parent cell, or micro-gametocji;e (Fig. 36, 1, i ), multiplies, on the other hand (Fig. 36, J, (?), and produces a number of small, active, male germs known as microgametes (Fig. 36, K, the most common cause of mortality in Grouse chicks can rarely be described as the direct cause of the death of adult birds, 324 THE GROUSE IN HEALTH AND IN DISEASE Life history of the Strongyle worm. definition and recognition of these conditions the health of the moor directly depends. Briefly put, we have two factors common to all epidemic diseases, the always present, occasionally harmful intruder, and the host ; that is to say the Grouse, at times successfully resistant, at times pathologically affected by the nematode worm. In examining the action of these two variant factors from the point of view of the moor-manager, all that is necessary to ascertain is (1) with regard to the Strongyle — what are the predisposing causes which affect its occurrence in the Grouse's caeca, in greater or less numbers with more or less harmful consequences ? And (2) with regard to the Grouse — what are the predisposing conditions that tend to raise or lower the bird's power of resistance to the ever present evil ? If we can get a clear conception of these two sets of contribu- tory causes we can proceed with some confidence to investigate measures put forward for the improvement of the health of moors. Before considering the conditions affecting the degree of infection of birds by the Strongyle worm, it is necessary to refer to the life history of the parasite itself. As will be seen in chapter viii., this portion of the investiga- tion has afforded the Committee no little difficulty ; the small size of the worm, and the fact that a great part of its existence is passed outside its host, have made it difficult to follow this parasite through all its changes of form. The proverbial hunt for a needle in a bundle of hay is simplicity itself compared to the labour of detecting the larval nematode (so small as to be visible only under a high-power microscope) in an acre of heather. In addition to the difficulties arising from the small size of the worm, the search was made more complicated by the presence of other free-living nematodes, very easily mistaken for Tricho- strongylus pergracilis. Some of these complete the whole cycle of their life in the soil, and are never parasitic at all. With very few exceptions every Grouse has in its body a varying number of Strongyle worms, of which the females MOOR MANAGEMENT 325 are each capable of producing many eggs ; these eggs pass from the body with the csecal deposit, and after three days' incubation on the moor, reach the larval stage. The csecal deposit is well known to all field observers, and is readily distinguished from the hard cartouche-shaped dropping of the main intestines by its light chocolate brown appearance and moist consistency. The number of the larvae in a Grouse-dropping varies enormously, and depends directly on the degree of infestment of the bird from which it comes ; in the case of heavily infected birds they may be reckoned in tens of thousands. The larvae during the earlier stages of their existence appear to have the power of lying dormant for an indefinite period, they are not affected by the frost ; a rise of temperature will at any period raise them out of their torpid condition ; excessive drought and perhaps the salt spray of the sea are the only conditions known to be injurious to their health. After passing through the casting of skins common to most nematode worms, and after a period generally to be reckoned in weeks, but probably never less than ten days, the larvae assume a resistant sheath and become active young nematodes ; they climb the shoots of the damp heather, and, like the East Coast fever-tick on the South African spear-grass, lie in wait for an opportunity to complete their life history by returning to their natural host the Grouse. Once the Strongyles have returned to their host the further stages of their life history follow in rapid succession. Absorbed with the heather shoot into the crop, protected in the gizzard by the sheath-like covering from the action of any but the sharpest grits, the encysted Strongyles pass once more into the caecum, and on the third day reach the adult stage ; the females become fertile, and three days later the myriad offspring set forth once more to infect the moor. It is only when the adult Strongyle is found in the caecum in large numbers that the health of the Grouse is appreciably affected. If we consider that birds may be packed on one portion of the feeding area, for perhaps weeks at a time, herded 326 THE GROUSE IN HEALTH AND IN DISEASE together by stress of weather or shortage of food, that the number of Strongyles will increase by geometrical progression as the birds get more heavily infected and therefore increasingly able to foul the moor, it is not difficult to realise, despite the countless thousands of larvae destroyed by drought, mishap, heather- burning, etc., how the moor may become more and more tainted, until at last every shoot of heather bears the seeds of " Grouse Disease." Power of Equal in importance to the presence or absence of the o?Grouse Strongyle is the second factor, the power of resistance of the individual Grouse. The fact that the normal Grouse, in the proportion of ninety -five to five, has its caeca charged with Strongyle worms shows that, under a certain set of natural conditions, the worms are not necessarily hurtful to their host. Upset the natural balance, and this at once ceases to be the case. This varying power of resistance of the host to parasitic or bacterial infection has long been a recognised commonplace of science. Recent scientific investigation seems to indicate that the power of resistance varies directly with the health of the subject, and as far as the Committee's investigation goes, the Grouse appears to be no exception to the rule. A bird in full health, weight, and plumage can carry his quota of Strongyles like an alderman his wine ; but once allow the vitality or weight to go below a certain recognised figure, then immediately the Strongyle worm appears to operate harmfully on the vitality of the bird. The caeca become inflamed, the digestive process is no longer effective, the moult is delayed so that the bird loses the fresh colour of its plumage, it declines in weight, and, after a more or less protracted resistance, eventually succumbs. Without going into the whole argument in support of these statements it is only necessary to say that the weight of the bird is the most easily recognised indication of its power of resistance to disease. That nine-tenths, if not all, of the out- breaks of " Grouse Disease " have their origin in the spring, when the food-supply is at its shortest, and when the bird is MOOR MANAGEMENT 327 in its lowest condition ; that in early spring the cock-birds, wearied out with fighting for their nests and mates, lightened in condition and without time to feed, die in the proportion of seven or ten to one hen ; whereas in late spring and early summer, when the hens are weakened after their moult, and light in weight through shortage of food during the sitting period, the relative proportions in the death-rate are reversed. ^ From the consideration of the two factors set out above, the immediate objective of the moor-owner stands out clearly — to keep the Strongyle infection at its lowest, to keep the power of resistance of the stock at its highest, and at the same time to maintain the greatest number of birds that the moor is capable of supplying with suitable food. Successful moor management may therefore be defined as Definition the maintenance of a margin in the power of resistance of the ^Mage- weakest individual Grouse, sufficient to enable it to overcome ^^^^ the greatest nematode infection to which the surrounding circumstances may render it liable. To put it briefly and in practical language : Moor management is the science of distributing the stock of birds over the moor, so that at no period of the year can any area be so infected by the Strongyle worm as to make it a source of danger to the least well-nourished bird {that is, to the bird of the lightest weight) on that area. In considering this definition it is important to realise not only the main factors connected with " Grouse Disease," but also the contributory causes which produce them, (a) the power of resistance of the Grouse, which varies directly with diet, moult and seasonal conditions, (6) the liability to infection, which varies with the number of larval nematodes on any given feeding-ground. These contributory causes in turn depend on the number of birds on the given area, the number of nematode eggs deposited in each csecal dropping, and the length of time ' N.B. — Investigation in the Frimley area has shown that light birds and birds not in good plumage die more easily from artificial infections of nematode worms, and measurements go to show that light and weakly birds of one year, without sufficient strength to feed themselves at the time of stress in winter and autumn, are the piners and diseased birds of the year following. Vide Keport, chap, xxi. pp. 469-470. 328 THE GROUSE IN HEALTH AND IN DISEASE that the stock has been congested on any portion of the ground. It must be clearly understood that " Grouse Disease " is not dependent on any fixed number of Strongyles in the caecal intestines, or that any fixed standard of power of resistance guarantees immunity from the disease, but rather that the epidemic depends on the relation between the amount of infection and the power of combating the same. That is to say, that the nematode infection which would be fatal to the weak bird might conceivably be the normal burden of the strong Grouse ; and that the same bird might carry with ease in autumn — when well nourished and fully feathered — ^the number of Strongyle worms to which he would succumb in spring when light in weight and short of food. If we realise this theory in its entirety we shall find ourselves on vantage ground from which the many and apparently contending aspects of " Grouse Disease," and the numerous hypotheses based thereon, can be readily explained. Theories of CERTAIN THEORIES OF DISEASE HELD BY SPORTSMEN AND Die'" ^^^^^ OBSERVERS. (1) Frosted First Theory. — ^A very common theory, especially on the ®^ ^^' west coast of England and Scotland, is that frost is the cause of " Grouse Disease." This theory is usually stated in the form — that " the frost of early spring browns the heather, birds eat the heather and die of indigestion." This is a very good example of an incorrect deduction drawn from properly observed natural phenomena, and of the ease with which secondary causes are confused with primary ones. It is quite incorrect to say that frost in spring is the immediate cause of " Grouse Disease," for the very excellent reason that of nearly two thousand crops examined by the Committee not one single crop has been found to contain a shoot of brown or frost-dried heather. It is, however, correct to say that when frost comes in late spring, or when the cold east winds scorch the young MOOR MANAGEMENT 329 shoots, the area of ground on which the birds can feed is reduced, and there may be therefore both a lowering of the Grouse vitahty through a shortage of the food supply, and an increased danger of infection by the Strongyle worm through the conges- tion of the birds upon a small area of feeding-ground. The old stick heather, ragged and sparse, is the first to suffer from frost, and is therefore of little use for food during the winter and spring. It is only in the thick six- to fifteen-year-old heather that green shoots can be found under the browned tops.^ On a badly-burned moor this may mean a very great curtail- ment of the food yield of the moor ; greater perhaps than the health of the weaker birds will stand. Second Theory. — It is stated that disease comes every seven (2) Periodic years : that it is a recognised order of creation, and that no unav^cSd-^ effective steps can be taken to alter the periodicity of its recur- *'''^- rence. This theory, like the preceding frost theory, is quite beside the point. In the first place, " Grouse Disease " does not occur on any moor in the regular order of once in seven years. The examination of some hundreds of Grouse records show that the disease occurs, on those moors which are liable to the epidemic, at irregular intervals of three to eight years. The ordinary sequence of events is, one year of disease, one or two years of recovery, two or three average seasons, one or occasionally two bumper years, followed by disease in the following spring. Disease after a record year is due partly to a heavy Strongyle infection in the winter months, resulting from an overstock at a time when the birds are packed together on the lower portions of the moor, partly also to the Grouse's decreased power of resistance arising from a heavier stock without a corresponding increase of the food-supply As has been already pointed out this food shortage is most marked in spring, and the outbreak of the disease accordingly occurs at that time. ' See chap. ill. p. 83. 330 THE GROUSE IN HEALTH AND IN DISEASE (3) Two Third Theory: Klein's Disease. — The third theory, asso- disease! ciated with what is commonly called Klein's disease, is that the mortality can assume two forms, the first or epidemic form (pneumo-enteritis), which sweeps the moor, and in which the birds are said to die in plump condition, fully feathered ; the other a lingering disease in which birds waste away and die only after loss of plumage and weight. The Committee have paid very close attention to Klein's disease, and the remarks on p. 153 should be read. It may be noted that in all the out- breaks investigated not one single case was found of birds dying in good condition, i.e., at normal weight. On seventeen different occasions during the course of the Committee's investi- gations keepers have reported birds dying plump and fully feathered ; in every case the spring balance has indicated that the birds referred to were below the normal weight, and visceral examination has shown that the cseca were charged with Strongyle worms. (4) Midges Fourth Theory. — The fourth theory put forward is that or gaa s. when birds die of disease on lightly-stocked moors it is impossible that they should die of shortage of food or by parasitic infection, and that therefore midges or gnats must be the cause of death. This theory is not supported by any ascertainable facts or data, and, as far as examination of the blood goes, there is strangely little evidence in its favour. It cannot be admitted that a shortage of stock on a moor is necessarily a guarantee of immunity from infection by the Strongyle worm, although it may lessen the risk of such infection. It will be shown later that moors in Yorkshire, which one hundred years ago were unable to carry three hundred brace to ten thousand acres without a certainty of disease, have by careful burning been made to carry ten times that stock without risk. Infection of a light stock can be brought about in various ways : — (1) If, in a hard winter, the birds are driven by snow off their own ground and congested on a small feeding-area for a MOOR MANAGEMENT 331 long enough time for the larval nematode to go through its changes and infect the heather, the birds may become so charged with Strongyle that they die as soon as they return to their own ground, however lightly stocked that ground may be. There are very few owners of high-lying moors who haVe not heard the remark : " The birds were quite healthy before the last winter storm ; as soon as they returned to the high ground they began to die." (2) " Grouse Disease " occasionally appears the second and third year after a severe epidemic, especially on wet, badly- drained moors, and this notwithstanding the small stock that may have survived the first outbreak. As has been shown in chapter viii.,^ the Strongyle worm flourishes best in damp surroundings, and it is possible that on a wet moor a smaller quantity of oVa may be sufi&cient to cause fatal infection. (3) On the west coast of Scotland a very light stock some- times contracts disease. West coast heather is, as a rule, of ranker growth and more open habit than what is found on the east coast ; it is therefore more liable to be scorched by the frost and cold winds of early spring. The food-supply in consequence is apt to become so short that the normal quota of Strongyle worms are enabled to become actively pathogenic without the aid of further and outside infection. Fifth Theory. — ^Another theory put forward is that a hard (5) Hard winter affects the health of a moor. This theory takes two w™*®^^- forms. First, that a hard winter makes for healthy stock, and secondly, that a hard winter causes disease in the following spring. These theories are mutually destructive, but, paradoxical as it may appear, both are conceived on a certain basis of truth. A hard winter tends to kill off sickly birds, to shift the stock and to mix the breed ; snow lying on the heather till far into the spring protects it from larval infection during the critical months of February and March, and so ensures a fresh, untainted 1 Chap. viii. p. 237. on corn. 332 THE GROUSE IN HEALTH AND IN DISEASE food-supply in April and early May ; lastly, heavy snow followed by floods tends to wash the moor clear of Strongyle larvae ; all these are factors which benefit the moor. On the other hand, a hard wintet may do incalculable harm if the birds are driven off the hill ground and massed for several weeks on a small area of feeding-ground. The winter storms, especially in the Highlands, drive birds off great tracts of heather land, with the result that when the food is at its shortest the local feeding-area is reduced sometimes to a half, sometimes to a tenth, of its normal size. The migration of Grouse is a question that has only recently been systematically studied, and some remarkable facts have been brought out as to the length of time for which birds may desert the high ground, i (6) Feeding Sixth Theory : Corn Theory. — This theory suggests that by eating corn in the stook birds are seriously affected in health, and die of disease in the year following. This is another example of faulty deduction from correctly observed natural phenomena. The fact that birds go oft the moor in October to eat corn on the low ground usually means that there is not a sufficient natural food-supply on the moor. If the birds are short of food in autumn and early winter it is quite certain that they will be still shorter of food in the spring when the carrying capacity of the moor is at its lowest, and it is easy to see how they will in consequence become liable to the hurtful influences of the Strongyle worm. It is not necessary to go into any of the other theories of " Grouse Disease " examined by the Committee. The majority appear to be based on a misinterpretation of natural phenomena, and in most cases confusion has resulted from mistaking the predisposing conditions for the immediate causes. All the theories on the subject fall into line with the solution put forward by the Committee, that the immediate cause of " Grouse Disease " among adult Grouse is the Strongyle worm. 1 Vide chap. i. pp. 28 et seq. MOOR MANAGEMENT 333 The next question that has to be considered is whether there Kemedial ,.,.,. _.. , .„ . „ measures. IS any proof that the liabihty to Disease can be artmcially controlled. Can it be shown that more birds can be carried on a moor if they are well distributed, and if their vitality and weight are raised by an increased supply of food at all times of the year ? The answer to this is undoubtedly Yes ! and the four following examples are put forward to show what results have been obtained on well-managed moors. Bolton Abbey Moors, Yorkshire, These are high well-burned moors with good grit ; they are well watered and considerable attention has been paid to drain- ing ; the patches burned on the moors every year are very large ; they have probably not always been so well burned as they are to-day, and the older heather takes three or more years to spring from seed after burning. The average annual rainfall is about 38 inches. The record given below is a very remark- able one, extending as it does over a century. The following points should be noted : — (1) That the yield of Grouse has increased from a minimum of two hundred to a maximum of over three thousand brace. (2) That for the first twenty years any year in which oVer three hundred brace was killed was invariably followed by disease, that is to say, that the same ground which now yields three thousand brace with safety, could not then give a bag of more than two hundred brace without risk from disease. (3) The difference in the time required for the moors to recover from the epidemic under the new and old con- ditions is very marked. When the moors were badly burned it used to take three to four years to get over an outbreak of disease ; in the last two outbreaks the season following the attack has shown an average yield. 334 THE GROUSE IN HEALTH AND IN DISEASE Bolton Abbey Moors near Skipton in Yorkshire (4.000 ACRES ANALYSIS OF BAGS Bran me a-ff iiei ^s^r 1151 1331 jf-r^ ««' &Sl S3i/ iSC, sm «^,'/ rj// nil S3)t 68 X 9J9/\ ss-d 03Q? 0811 scoo stso S600 s*oo sm HOO ^400 4tm 3S0O 3100 JAW itoo 2S00 1400 ZIOO MOO ites isoe 1900 /too 1000 too SOO wo zoo __ Pf p_J « H R? C3 I b=d —I • [ ft + « ZJ ll — W fe/MnrAre^Keor BK) —— S yawL V Aif£ii/ici or Bxcs %■■ No SuBOTmc iOiansc *toTE In ot/dihai le tht numoerj slated He Ga/meeperi lavemllul Mttumji dunug /He last ^lyears a/i anrage afSOOCQCIi An* during tig laiKr purt oflDe Season MOOR MANAGEMENT 335 These moors are still improving from the effect of years of regular and heavy burning and draining. There is every reason to suppose the rate of heather growth will increase, thus affording an extended area of ground bearing a full crop of food. An analysis of results is given in chart form on p. 334. Broomhead Moor, Yorkshire. This is a very remarkable moor. It has been well cared for for over forty years ; it is now probably one of the best, if not the best burned moor in England or Scotland, with the result that it has not only the thickest but also the quickest growing heather that the Committee have seen anywhere. There are not twenty square yards of old stick heather on any portion of the ground ; there is a larger proportion of six- to twelve-year-old heather than on any moor the Committee have investigated, a bigger stock of birds is carried to the acre, and disease has not occurred for oVer thirty years. On examining the Game Records the following points are brought out :— (1) The steady growth of bags from two hundred brace before 1870 with disease recurrent every few years, up to two thousand seven hundred brace per annum with no danger from disease. (2) In the last decade there appears to be a slight set-back, but this is more apparent than real, and unsuitable weather in the shooting season is largely responsible. (3) There is now a larger stock on the ground than ever, and the owner with forty and the keeper with fifty-one years' experience of the moor are agreed that the maximum yield has not yet been reached. The points about this moor that are especially noteworthy to moor-managers are that : — (1) Though there is no long heather the birds are kept on the moor all the winter. 336 THE GROUSE IN HEALTH AND IN DISEASE Broomhead Moor neap Sheffield in Yorkshire '*.000 ANALYSIS ACRES OF BAGS BR1C£ (8i8 61 6i-6T 68 -/P 73/7 78 82 83-87 88-92 93-97 98 -OZ 03-07 eeoo itOO eeoo zooo 1800 1600 moo IBOO lOOD 800 600 WO 200 1 >.« ^* 1 1 1 10 YiAKLY AvaiAse " "" '"°°^""' S YCfiRLY AViRACe. MOOR MANAGEMENT 337 (2) Although the moor is relatively a small one, and is burnt in large patches, yet the total acreage burnt is only with difficulty maintained at one-twelfth of the moor per annum. (3) The management of the stock and methods of driving ^ have undoubtedly much to do with the health of the birds on the moor. <4) The moor is all above the 1,000 feet line. (5) The climate is dry, the average annual rainfall being about 30 inches. (6) Beautiful white quartz grit is found all over the moor. (7) There are about a dozen good springs, and a deep burn runs through the centre of the moor. A chart is given on p. 336 showing the gradual improvement in results which has followed improved methods of manage- ment. It should be mentioned that the steady increase in the stock commenced about 1872, and that it was just before that date that close and constant heather - burning was first introduced. Carron Moor, Morayshire. A moor of about 3,000 acres, of which about 1,000 are flow ground, and the rest heather. The altitude ranges from 700 to 1,300 feet. Previous to 1897 the heather-burning had been neglected, in many parts the heather had grown to a height of 3 feet or more ; since that year the burning has been most carefully and thoroughly done, when possible. The heather all over the moor shoidd continue to improve, for it has only been regularly burnt for the last fourteen years, and during some of that time, owing to bad weather, little or no heather could be burnt. A considerable quantity of old heather still remains to be burnt, and much that has been burnt has not yet reached the most valuable stage. Good grit is abundant, and great attention has been paid to drainage, A moderate stock . of sheep is carried on the ground. ' Fide pp. 415 et sej, and p. 446. Y 338 THE GROUSE IN HEALTH AND IN DISEASE Carron Moor Morayshire 3,000 ACRES (ANALYSIS OF BAGS 1897 ■8 ■9 1900 1901 -i „ 56' I909....S99 „ 'Oli'"' ■■ t9l0....9^ „ /6S4- MOOR MANAGEMENT 339 In 1910 the experiment was tried of introducing an artificial water-supply to the drier parts of the ground by means of dew pans. The results appear to have fully justified expectations ; in one case it was observed that five coveys were hatched in the immediate vicinity of a dew pan, where there were no young birds before. The results are conclusive so far as they go, but the experiment has not been continued long enough to admit of absolute certainty. The years 1907-1908-1909 yielded an average bag of 1,114 brace, as compared with an average bag of the years 1897-1898- 1899, of only 241 brace, showing an increase of 873 brace. In 1910 the bag was upwards of 1864 brace. No disease has occurred since this improvement began. From the evidence available it would appear that the whole of the birds are bred on the moor, and the suggestion that so large a bag can only be obtained by the immigration of birds from neighbouring moors is not supported by the facts. The progress of the stock is carefully watched from the date of hatching to the commencement of the shooting season, and it is always found that the total bag corresponds to the prospects at the nesting season ; there are no berries on the ground to attract neighbouring birds, and the first day's driving always takes place before any of the surrounding moors are driven. Towards the end of the year there is often an immigration of birds from other moors ; but these visitors arrive after shoot- ing has ceased for the season, with the exception of the game- keeper's annual crusade against old cocks. The whole stock has been known to leave the moor in time of heavy snow, and to remain away till the snow has disappeared ; but such migrations have not been found to affect the number of birds on the ground at the next nesting season. The owner of the moor has drawn the following deductions from the foregoing facts : — (1) That it is possible, by improving the heather, to raise the permanent stock of Grouse that a moor can carry 340 THE GROUSE IN HEALTH AND IN DISEASE Cawdor Moor. Nairnshire 30000 ACRES ANALYSIS OF BAGS Brace mot 65-69 70-7^ 75-79 mt 85-89 90-Ot 95-99 mof 05-09 10-11 6000 J600 5600 5400 5200 SOOO 4600 4600 4400 4200 4000 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 I 1 J -—J I r I I fO y^fiRLr AvCRflGE. S YeAftLy Average MOOR MANAGEMENT 341 without fear of disease developing locally, i.e., among the home stock of Grouse. (2) That drainage is very beneficial. (3) That an abundant supply of good grit is essential. (4) That Grouse driving is largely responsible for the increase. (5) That the limit has not necessarily been reached. (6) That the introduction of an artificial supply of water may be beneficial in a dry season or on the drier parts of the moor. Cawdor Moor, A very fine moor not yet fully developed or arrived at its full carrying power, with good young heather. The following points in the record should be noted : — (1) The improvement in each decade. (2) A slight set-back in 1890 to 1900, probably due to the moor being less well cared for during that period. (3) The period 1900 to 1910 shows a marked advance, owing to regular driving and improved methods of manage- ment, (4) The time required for the moor to recover from the effect of the 1907 epidemic was one year ; on all previous occasions it took upwards of four years to get back to the average yield. This moor is in the centre of a Grouse-bearing district, and will probably always be liable to disease from overcrowding by birds from higher and less well-burnt moors in late winter and early spring. This danger will remain until some system is adopted for the proprietors taking joint action to regulate the stock in good Grouse years. The bag in 1910 was 7,180J brace and in 1911 (a bad season in the district) it was 3,443^ brace. The moor is probably now capable of yielding an average yearly bag of 5,000 brace as compared to 600 brace in 1860 to 1870. 34.2 THE GROUSE IN HEALTH AND IN DISEASE From the examples that have been given four deductions can be made : — (1) That it is possible by careful management to raise the permanent stock of Grouse on a moor, and do so without increasing the danger of infection beyond the power of resistance of the individual bird. (2) That during the various stages or periods of develop- ment of the carrying capacity of the moor there is a corresponding limit of stock which it is dangerous to come up to, and fatal to exceed. (3) That as far as yet ascertained the limit has not been arrived at on any moor beyond which a permanent increase of healthy stock is not possible by improved moor management. (4) That, though many moors by their proximity to less well-managed moors, and owing to the difficulty of getting the stock killed in a good year, immigration, abnormal seasonal conditions, etc., cannot entirely escape the ravages of disease, yet there is every reason to believe that the disease is both rarer, less hurtful in its incidence, and quicker to pass away on the well- managed than on the badly-burnt moors. CHAPTER XII HEATHER-BURNING The student of the heather-burning question will be struck, from the very outset of his inquiry, by the curious fact that while all parties are agreed that there is the closest possible relation between the state of the heather on any given moor and the health of the birds on that moor, there is the greatest divergence of opinion, not only as to what are the best methods of burning, but even as to what are the special characteristics of a really well-burned moor. The vexed question of the relative values of autumn- and spring-burning, the percentage of a moor that it is advisable to burn in any given year, the effect on the heather of the presence or absence of sheep, the limit of sheep stock desirable, the proportion of long heather to be left for spring feeding or cover, the management of the steep slopes for winter feeding, the methods of burning — ^patches, blocks or strips — and the treat- ment of the various descriptions of moorland, all give rise to a much greater variety of opinion than the difference of local conditions appears to justify. In the previous chapter, the findings of the Committee have been discussed in relation to the various theories which have been put forward as to the causes of " Grouse Disease " ; in the present chapter it is proposed to discuss the practical steps that must be taken to prevent its occurrence by : — (a) Raising the power of resistance of the Grouse ; (b) Lessening the risk of nematode and coccidian infection. With these objects it is intended, in the first place, to trace briefly the history of moor management in the last century, 848 344 THE GROUSE IN HEALTH AND IN DISEASE to show how blind but intelligent experiment has slowly been working its way towards comparative hygienic success ; to see where methods have failed through incorrect deductions from observations of natural phenomena ; to indicate broad precepts of moor management in accordance with our present standard of knowledge ; and lastly to lay down lines on which further experiments can be made with reasonable prospects of success, heather °' ^^ *^^ early days of Grouse shooting, when shooting rents burning. were low or non-existent, and the Grouse was an appanage of the sheep farm, not the main rent producer of a hill property, the moorland in the majority of cases was burned by the farmer and his shepherds. The methods used were rough and ready, but effective. The object, as set out in the tack or lease, was to burn one-tenth of the moor ; the driest and most windy days were chosen, and, provided the hirsels were burned approxi- mately in the authorised proportions, the matter of a few acres more or less in a single burning was not considered of much importance. Judging from occasional bags recorded it is probable that during this period the actual stock of Grouse throughout the country was often very considerable, but they were seldom fully shot so that the recorded bags are so scanty that an exact comparison witli the results of the present day is impossible. In the middle of the last century in England, and in Scotland a few years later, railway facilities, improvement in guns, increase of wealth, and, more than anything else, fashion, made the sporting value of the Grouse moor gradually approach the grazing value of the farm. The Grouse, up to then the occasional victim of the landlord and his friends, or of the poacher for the pot, became all at once a saleable article, for which there was, and has been since, an ever-increasing demand. The moor-owner was quick to realise the enhanced possibilities of his property, keepers were appointed to even the smallest areas of moorland, and the rights of burning the moor were transferred from the shepherd to the keeper, under the mistaken idea that the policy of burning to benefit HEATHER-BURNING 345 Grouse, not sheep, would at once increase the yield of birds. It is a curious fact that, while the average man can predict with some degree of certainty the immediate result of any change in the existing order of things, the correct calculation of even secondary consequences requires the attention of brains of a very different calibre. When the landlords in their wisdom appointed the keeper to the r61e of moor-burner they achieved their immediate aim — better cover for shooting over dogs ; but they gained also a second and not less noteworthy result, a drop both in the average bag of Grouse and in the grazing value of the hill-ground, a thing neither foreseen nor in any way desired. Founded on latter-day experience the reason for this is not far to seek. In the dogging days long heather was the ideal. " Keepers' delight," when applied to 3-foot heather, is still a recognised and but too often well justified term. The keeper, acting up to his lights and wishing to show the best sport on the Twelfth, not only stopped the shepherd from burning big stretches of heather, but stopped him from burning the heather at all. In books of sport in the year 1863 places are mentioned— as splendid Grouse ground — " fifteen hundred acres of heather without a single break ! " This method of heather culture was admirable for approaching wild birds ; in these jungles a covey once settled could be massacred at ease with " snap-hance " or breech-loader. Unfortunately, the change of methods was not equally satisfactory with regard to the health of the moor, and a very rude awakening was not far distant. A few lucky seasons, with a heavy crop of heather seed for food in winter and early ripening shoots in spring, gave in certain favoured districts an increase of bags by improving the con- ditions for approaching the birds ; then a cold summer followed by a winter with late spring frosts, and a seasonal shortage of food intensified by an overplus of old stick heather, led to the inevitable result — a general outbreak of disease. As early as 1857 there were reports of heather on certain 346 THE GROUSE IN HEALTH AND IN DISEASE moors " man high " — ^by the sixties the whole effect of the shepherds' burning had passed away, and in many districts where the non-burning practice was at its height, not only were there few birds and disease frequently recurrent, but the graziers' complaint became more and more common — ^that there was not enough young heather and grass to feed the sheep-stock. At this period the relations between sporting tenants and sheep- farmers became so strained that big sheep-farmers, then a well-to-do class, used in many districts to rent the shooting as well as the grazing of their holdings, and so get the control of heather-burning into their own hands. In 1871 and 1873 the Game Laws Commission investigated the relations of the sporting and farming interests, and some very interesting facts were elicited. Not the least important of these facts was the similarity of heather conditions required for sheep and for Grouse. This was brought out by the evidence of farmers who had leased the sporting rights of their farms, and who spoke of doubling and trebling the bag of Grouse by burning tracts of ground in order to get the land back into the proper rotation for sheep, viz., one-tenth of the moor burned per annum. The reports of these and other successes obtained by heavy burning were not long in being spread abroad. Partly from increase of knowledge, and partly to satisfy the sheep interest, more intelligent methods were pursued. On many estates the principle was adopted — " The shepherds light the fire, the keepers put it out." As a principle rather than as a practical usage this is not far from the ideal. The shepherd wants the acreage burned for food, the keeper wishes the patch or strip method maintained for the segregation of birds. Matters in the early seventies were thus proceeding through the usual course of friction and inquiry towards mutual under- standing and settlement, when in 1872 and 1873 the great disease year occurred. Just as 1881, by the introduction of the Ground Game Act, may be described as the Jena of the rabbit, so for a very HEATHER-BURNING 347 different reason 1872 and 1873 may be said to be the Austerlitz of the Grouse. From end to end of the Grouse area the epidemic created unparalleled destruction ; authorities realised that old methods must give place to new ones, and from that date the intelligent management of moors may be said to have commenced. Broadly speaking, we may divide the history of heather- burning into three periods, not always synchronous, but through which the majority of moors have passed at one time or another. 1800 to 1850, when the heather was burned by the shepherds in wide tracts, and one-tenth of the moor was fired every year without any attempt at scientific burning. During this period shooting rents were low. Large blocks of land were hired in Scotland for as many sovereigns as they now fetch hundreds of pounds. The frequently quoted example of the sporting rights of the Island of Lewis, hired by Lord Malmesbury for a period of years for £25 per anmmi, is a case in point. At this time few moors were rented in England, and although Grouse driving had just begim in Yorkshire the results generally were not great, and the flint-lock, contemporary writers tell us, still had its devotees in the firing line ! Mr Snowie of Inverness was the only shooting agent for Scotland, and the names of moors for hire could be contained on a single sheet of foolscap. 1850 to 1873 marks the transition period of heather- burning. Moors generally were taken into the hands of owners and shooting tenants, the patch method of burning came into fashion, and the proportion burned, as far as records show, dropped from one-tenth to one-hundredth part of the moor burned per annum. In this period great strides were made towards fitting out shootings with lodges, approach roads, and other conveniences. Large sums were paid out in the wilder and poorer districts, and a great deal of employment was given. Moors were let for sheep and Grouse at about the same figure. It is instructive to note that to-day on many of the same moors 348 THE GROUSE IN HEALTH AND IN DISEASE sporting rents represent five, in cases ten times the value of the grazing rents. The third period begins with the years of disaster 1872 and 1873, which were followed by four years of recovery and very restricted bags. These lean years were the immediate cause of the study of Grouse pathology. The investigation has continued more or less ever since, and after passing through the vicissitudes customary to research in a new field, has cul- minated in the comparatively extensive knowledge of the present day. Notwithstanding the fact that Cobbold had indicated in 1873 that the cause of the great outbreak was the Strongyle worm, the first move towards an improved system of manage- ment was not in the right direction. The moors had been indifferently burned so long, that in order to catch up the rotation recourse should have been had to big fires rather than to the patch or strip system of burning. This, however, was not realised. Many land-owners, seeing that " patch-burned " moors were less affected by the disease than moors on which no heather had been burned, jumped to the conclusion that it was the smallness of size of the individual patch, and not the total area of the burn- ing that was all-important. This belief is prevalent in many localities to-day, and it is no exaggeration to say that to this error, more than to any other cause, is due the persistent recurrence of disease. Conelu- From the foregoing history of past failures, and the knowledge scientific investigation has given us, we can proceed to lay down with some approach to certainty the following rules of heather- burning, and the reasons on which they are based : — (1) That, in order to maintain the vitality and therefore the power of resistance of the Grouse, the moor must be so burned as to keep the food-supply at its highest. (2) That the early spring food-supply is the index of the carrying capacity of a moor, and that therefore heather- burning must be so ordered as to insure the maximum yield of food in February, March, April, and May. sions. HEATHER-BURNING 349 (3) That the patch or strip method of burning must as far as possible be pursued in order to segregate the birds, and thereby lessen the risk of infection by the Strongyle worm and the Coccidium. In discussing the question of burning for food two difficulties at once arise : — (1) That of persuading the average moor-owner that by burning small patches with a small staff he cannot possibly get over his moor. (2) That of persuading him that at any time of the year the birds can be short of food, or that there is any real difference in the heather supply on well and on badly burned moors. To convince him of these facts it is necessary to go into figures, and those set out below may be taken as a reasonably accurate statement of conditions that obtain on many average if not model moors. On the ordinary 5,000 to 6,000 acre moor in England, and Estimate the corresponding 10,000 acre moor in Scotland, on which one turned on thousand to fifteen hundred brace are killed in a good average average year, and on which two keepers and one or more watchers are maintained, the landlord thinks he is doing all that can be expected of him, if in addition to the keepers, six to eight extra hands are employed in spring to burn the moor. Speaking generally, after a careful investigation of east and west coast conditions, of high and low moors, a good spring- burning season will give an average of ten whole days or twenty half days on which the hill can be fired. Taking into considera- tion dry and windy weather when the fire goes well but requires great control, and wetter conditions or less wind when the fire does not " run " so fast and may be managed by a couple of men, it may be calculated that on an average each keeper, dividing his gang to the best advantage (each gang consisting of not less than two parties), will not burn more than thirty, or at the very outside forty patches or strips in a full working day. That is to say, if the small patch or narrow strip method 350 THE GROUSE IN HEALTH AND IN DISEASE of burning is followed (i.e., burning in areas of from one- eighth to half an acre), the two keepers and their parties will burn 20 acres a day, or a total of 200 acres of the moor in a year. Those who have not had a practical experience of heather- burning are apt to hold exaggerated ideas as to the amount of work that can be done in a single day's burning. It is only when facts and figures are subjected to a careful scrutiny, and the amount both of the day's work and the season's results are thoroughly gone into, that the smallness of the area burned becomes apparent. If we admit this contention to be correct, a little simple arithmetic will show that 200 acres on 6,000 acres of moorland is one-thirtieth of the total area, that is to say that, if the heather is regularly fired in rotation it will be thirty years, or in the case of the 10,000 acre moor fifty years old before it comes to its turn for burning. If we consider that every year is not a good burning year, and that on many moors on the west coast a good burning year occurs only once in three years, that some districts suffer from fogs, " haars," and mist ; that others get so dried up after a continuance of east wind that it is dangerous to burn at all ; that in Scotland the high ground in a late spring is covered with snow until the end of March; that there are the additional difficulties of suddenly rising winds, late dews, and of getting men away from their holdings, etc., it will be easily seen that a moor may go for a series of years with only one-sixtieth or one- himdredth part of its total area burned, and that instead of catching up the heather rotation in force when the sheep-farmer was responsible for maintaining it, many moors are steadily going back in their yield of young heather, and therefore in their power of maintaining a healthy stock of Grouse. The second difficulty, viz., of persuading the moor-owner that his birds may be short of food, is not less great. Many proprietors only see their moors in August — every head of heather in bloom and green shoots on every stem. He sees sheep grazing at the rate of one to the acre. It is very difficult HEATHER-BURNING 351 to persuade him that at certain seasons there may not be enough food for at least an equal number of Grouse. Let it be at once admitted that through the summer and autumn, even on the worst moors, there is abundance of food ; but then at that time, except for a previous infection, Grouse do not die. Let the doubter visit the moor in March, when the heather seed has fallen from the pod, when the young heather up to four and six years old is frosted a clarety red or brown colour, when the old stick heather sparsely distributed and bare of side shoots does not carry a " canopy " with which to keep out the withering effect of the cold winds and frost, and he will find a very different state of affairs. Careful examination will show that the close-growing six- to fifteen-year-old heather with a thick matted covering affords the only feeding at this time of year, and that even here the shoots are green, not at the top, but half-way down the stem, where they are protected from the weather. It is at this time that the real test of moor management Rotation, is seen, and a little careful study will prove to demonstration certain facts not found in the philosophy of the " small patch " enthusiast; Granted the premises set out above, it follows that, if the moor is being worked on a hundred years' rotation, the total amount of spring-feeding heather, that is to say, the amount that lies between six and fifteen years of age, is roughly 9 per cent, of the total area of the moor. If the moor is burned on a fifty years' rotation, which is the rotation of the majority of moors to-day, the amount is 18 per cent, of the total area. If, however, the heather is burned on a fifteen years' rotation, the rotation the Committee advise, the amount of edible heather represents nine years out of a total of fifteen, i.e., 60 per cent, of the total acreage of the moor. That is to say, if we admit the early spring months to be the critical time in the life history of the Grouse — ^no great admission seeing that it is in spring that disease invariably appears — ^we shall realise that a well- burned moor can carry seven and a half times the stock of the moor burned on a hundred years' rotation, and nearly four 352 THE GROUSE IN HEALTH AND IN DISEASE times as much as that of the average moderately burned moor. These figures may possibly be challenged ; but with regard to the area burned the proof is perfectly simple. Employ a surveyor to measure up the patches of a strip or patch-burned moor, burned in 1910- — a very good burning year — compare the acreage with the total area ; the result will astonish many landlords who habitually boast that they burn one-tenth of their moor every year. It will perhaps be argued that the six- to fifteen-year heather is not the only spring feed, that even the stout stick heather will present occasional green shoots, and therefore afford some small measure of sustenance to the Grouse in the spring-time. This is true, and it is a fact that, faute de mieux. Grouse are able to exist on an unbumed moor. It must, however, be remembered that they require probably twice or three times as much of the sapless, partly dried-up heather of April as they do of the more succulent shoots of summer and autumn. The weights of crop contents show that late winter and early spring up to two hundred and fifty grains of heather are found in the average afternoon crop as against fifty grains at any other time of the year. It is therefore reasonable to say that as the Grouse have to increase the amount of their food they will naturally go to those places where edible Calluna is most readily obtained, and thus by congestion of the stock on a small area will not only over-crop the food there, but also, as will be shown later, will be exposed to an increase of infection by the nematode worm and by the Coccidium. Before leaving the question of the comparison of feeding areas of well and badly burned moors, one further point should be mentioned. On a well-managed moor the heather burned is all under twenty years old, and when it is burned the young heather springs from the root the same year. On a badly- burned moor, where old stick heather forms the main crop, the heather springs from seed,^ and in many cases only affords 1 Fitfe Plate XX., fig. 2. HEATHER-BURNING 353 food for Grouse after the area burned has passed through suc- cessive stages of grass and cross-leaved heather varying in point of time from six to twenty years. If the soil has a tendency to grow bracken the heather may be lost for ever. That is to say, in a fifty years' rotation moor, probably 20 per cent, of the moor is either black ground, bracken, grass, or cross-leaved heather, and is not yielding its proportionate quota of food. When we consider this loss of food area as well as the generally recognised fact that on a frequently burned moor the heather grows thicker and more luxuriantly than on one that is badly burned, it is no exaggeration to say that the food-bearing capacity of a moor at its best and worst is as ten to one. This change in the flora of a moor after burning is specially noticeable in the case of accidental fires, such as occurred on a large scale in Yorkshire in 1887 and 1893. Accidental fires are commonest in very dry weather, and thus there is a danger of the peat and soil being burned to a depth of several feet, thus destroying the roots of the heather. The second reason for burning is to keep the birds at all seasons split up over the ground. Grouse frequently get together into big packs for purposes of safety after frequent disturbance, or for shelter on the approach of storms, or in search of food, or to avoid snow or drought, or to prepare for migration, but, once the immediate cause of packing is removed, their instinct is to get away from their brethren and take up their family life apart. To help the, birds to develop this instinct, the patch or strip method has been advocated in the past, and, provided always the strips and patches in their totality suffice to maintain the food yield of the moor at its highest, no better system could be adopted, The minor point of whether narrow strips or square patches are advisable is not worth discussing ; keepers have their fancies, self-appointed authorities will air their views ; it is probable that both methods can be used with effect, each to suit the special circumstances of individual moors. The object to be aimed at is clear, that every bird should z 354 THE GROUSE IN HEALTH AND IN DISEASE have its tufts to nest in at the edges of the burned ground, its bare ground to sun itself in and on to which to take out its chicks ; its older heather for concealment, its breast-high 6-inch heather for feed, its well-matured heather for seed and shelter in winter, and, finally and of most importance, its six- to fifteen- year-old heather to keep it in health and vigour in early spring. In cases where it is impossible through the wetness of the season, shortness of labour supply, etc., to get the moor thoroughly burned in strips or patches, it may be asked whetiier it is not better to abandon the small patch system and burn a large acreage of moor ? The answer can be given with no uncertain voice — patches are only a secondary consideration, the first essential is to get the proper proportion of the total acreage of the moor burned each year. Apart from the destruc- tion of Strongyle larvas by fire it must never be forgotten that it is the sufficiency of the food supply that enables birds to stand a heavier infection of this parasite. On Broomhead and Moy moors, which carry regularly the highest stock per acre, and are among the best burned moors in England and Scotland respectively, the patches burned are large and disease is practically unknown ; but so also is old stick heather ! Methods of Having laid down the reasons which make heather-burning burning. necessary, the next thing to consider is the various qualities of soil and heather into which a moor is divided, the treatment of each, and the limitations, some natural and some artificial, which stand in the way of a complete realisation of the object in view. Old heather should be burned in strips, for when old stick heather is burned the fire is so hot that the roots are charred and killed ; in this case regeneration can only proceed from seed, and if the burned areas are narrow, self-seeding is materi- ally helped by wind-blown seed while only a small proportion of the total area is rendered destitute of cover. While it is necessary to burn off blocks of old heather in strips, it is advisable at the same time to get a considerable total area burned on each beat of the moor. PLATE XX. Fir:. 1. CjullvHii 'nihjiirix (Common Heather or Ling). Showing form of ])lant when gTo^\ing fi'om the root — first j^eai's growth. Ilppn^llrp. 355.] Fn:. 2. Culliiiiii riihi,if!x fComnion Heather or Ling). Showing form of jilaut when growji^Jlam seed. HEATHER-BURNING 355 Sheep always rush to the newly burned ground for the Sheep. sweeter grasses that grow there, and unless there are good stretches of burned ground for them to feed on, they will con- centrate on the small isolated patches and pull up all the young heather plants as they spring from seed. Every one who is acquainted with a moor in autumn must have observed the hundreds of little brown shrivelled-up heather seedlings pulled up by the sheep's teeth on every patch of newly burned ground.^ To obviate this wholesale destruction it is sometimes considered advisable, where the sheep stock is heavy and the moor has a tendency to go back to grass, to fence oft areas of old stick heather for two or three years after burning. This gives the young heather a chance of coming away, and once rooted it can defy the efforts of the stoutest-toothed " black-face." Old heather should, whenever it is possible, be burned " against the grain," that is to say, against the lie of the heather sticks. " Back-firing " or burning against the wind gives a very clean burn, the fire travels slowly, and destroys not only a larger percentage of the stalks of the heather, but also burns into the " fog " or moss which surrounds the roots of old stick heather. Owing to the shortness of the time available for burning in an average year, dampness of the soil, etc., " back- firing " is not always possible. In the case where an overcrop of partly charred sticks have been left it is advisable to run a fire through the burned ground a second time if possible in the second or third year following the first burn. This second Second firing has the effect of clearing the ground of the charred heather "''°™g- sticks and burning off the moss which, having been exposed to the air, is drier than at the first time of kindling. This affords a good clear sbed-bed on which the wind-borne heather- seeds rapidly establish themselves. The very greatest care must be taken of steep banks. Steep faces. especially those facing south, as these are the places that in time of snow give shelter and food to the Grouse. It must be understood that careful treatment does not mean allowing 1 Vide PI. XX., Fig. 2. 356 THE GROUSE IN HEALTH AND IN DISEASE "Flow" ground. Knolls. North slopes of hills. such places to run into old stick heather. Many keepers are so frightened of touching these winter feeding-places that on many moors the heather in these places has become rank, and is rapidly losing its value as winter food. Burning on steep banks should be carefully done so as never to reduce the total yield below the minimum which is necessary for food in time of snow. In the interest of both sheep and Grouse wet " flow " ^ ground should be burned in big stretches outside the ordinary rotation — ^if possible once in every six years. Flow ground usually overlies deep, damp peat, and is therefore protected from the full effects of the fire ; the grass and the stunted heather in consequence come away quickly from the root. It is often difficidt to burn flow ground owing to the heather being broken up into tussocks, and the driest weather should be chosen for the task. Knolls and hillocks are the favourite haunts of the Grouse, and however small they are, never more than one-third should be burned at one time ; the keeper's aim should be to provide in this way both food and cover for the birds frequenting them. The keeper should invariably get at the northern slopes of his ground as soon as the opportunity occurs. On high moors late snows make this possible only once in half a dozen years. Grey heather killed by snow or frost should be burned wherever it appears ; it is absolutely useless for food, and serves no purpose beyond cumbering the ground. Probably also heather which has been damaged by beetle should always be burned, as it is very doubtful whether it ever recovers from the attack of this pest. 1 By " flow " ground is meant the flat stretches of peaty land where, owing to the retentive nature of the soil, the surface water lies in pools and channels between tufts or tussocks of heather ; it is to be distinguished from marshy or boggy land where the water lies in suspension below the surface. Flow ground cannot as a rule be drained owing to the absence of a natural " fall," and even when drains are out the nature of the soil is not sufficiently porous to make them effective. Flow ground grows a poor quality of stunted heather usually mixed with sour-looking grass, yet Grouse are often found to frequent it during the day time, especially when it lies on a high plateau or immediately under the crest of a ridge. HEATHER-BURNING 357 Peat hags should be burned when the ground is not too Peat dry. Grouse are particularly fond of broken peat ground, and ^^^^i the food supply of short gnarled heather that grows there should be maintained at its highest. The peat itself occasion- ally gets on fire, and has been known on occasion to burn right down to the bed rock. In one or two cases that have come to notice excellent heather has grown on the mineral soil thus exposed. As the new growth in such cases may take twenty or thirty years to come up, such burning is outside the rotation that even the most progressive of moor-owners would care to adopt. The sides of bums and streams are most important features Bums and on a moor ; they are the favourite nesting places of Grouse, ^ ''®^™®- they afford shelter during storms, and are places where food can be obtained in times of snow. They should be carefully burned in very small patches, special care being taken to clear up the immediate burn-side and prevent its being used as a shelter for vermin, particularly for stoats, who otherwise use it as a convenient covered way to reach their prey. It is hardly necessary to point out that in burning a moor Burning the keeper must consider the method in which the shooting °^ ^^°^ ' is carried out. In the case of the driving moor broad belts should be burned immediately in the rear and patches immedi- ately in front of the butts to facilitate the " picking up " of Grouse ; settling ground with good cover should be left in the direction towards which it is intended to drive the birds. In the case of " dogging " moors, favourite banks should have a special allowance of long heather into which the birds can be worked at the end of the day. In deer forests " the beds " on which deer lie in the sheltered corries should be lightly burned. Heather can be burned at all times of the year in England. Limitation In Scotland, by statute, heather-burning is confined to the bumingr'^ period from November 1st to April 10th. On high wet moors an extension of the period to April 25th can be obtained. In Wales, by custom, burning is usually carried on during the spring months. Autumn- 358 THE GROUSE IN HEALTH AND IN DISEASE As soon as it was established that the health of the Grouse burning, depended not only on the distribution of edible heather, but also on the total extent of the supply, it became a matter of primary interest to the Committee to decide whether in their opinion the burning season should be extended, and how the results of autumn- and spring-burning were to be compared. The investigation was begun by sending an inquiry paper to correspondents, asking for their experiences of autumn- burning ; the time taken for heather to grow again when springing from the root and from seed respectively ; the opinion of sheep farmers as to the merits of the two methods and the character of soil least and most suitable for autumn-burning, based on a comparison of results obtained. In neighbour- hoods where heather had never been regularly burned in autumn, correspondents were asked to burn patches in spring and autumn side by side and to compare the results. The idea was intelligently taken up and thoroughly worked out, from the south of Wales to the north of the Highlands. The results of the observations taken have brought out the following conclusions : — (1) That in the interests of sheep and Grouse autumn- burning is advisable on all moors. (2) That it is necessary on large moors. (3) That it is the only possible method of getting high ground with a northern exposure into a proper rotation of heather crop. The Committee are further of opinion : — (a) That in the North of England the evidence goes to show that, whether springing from the root or from the seed, the growth of heather following autumn- and spring-burning is identical. (6) That on the more northern moors the heather is probably slightly slower in reaching maturity after autumn- burning, especially on shallow peat or hard ground, (c) That, while there is a certain prejudice, especially amongst older keepers, against autumn-burning, this HEATHER-BURNING 359 prejudice did not appear to be founded on substantial grounds ; as far as the Committee were able to learn, the majority of those who expressed themselves opposed to autumn-burning were found on examina- tion not to have themselves tried it, and to have based their opinion either on general reasons or second-hand information. (d) That on 95 per cent, of the moors in England on which autumn-burning had been tried the practice had been continued with the full sanction and approval of the sheep farmers interested. (e) That at least 75 per cent, of the larger moors examined are insufficiently burned, and that in many cases an extension of the burning period would enable a larger stock of both sheep and Grouse to be maintained. (/) That autumn-burning is necessary in the interests of the health of the Grouse and sheep, and that legislation in Scotland making it permissible to burn after October 1st should be introduced into Parliament without delay. With a view to further ascertaining the opinions of sheep- Opinion of farmers on the subject of heather-burning, a meeting was farn^rs. arranged between representatives of the Committee and a number of sheep-farmers from different districts. The views expressed clearly indicated that in the opinion of sheep-farmers there is not enough heather burned for either Grouse or sheep on the majority of moors in England and Scotland, and that there is a general wish on the part of sheep-farmers on heather ground that more heather should be burned. The farmers further stated that they would be glad to try autumn-burning in co-operation with owners, and that they could probably give more assistance in the autumn than in the spring, because in the spring they are usually busy with sheep that have returned from wintering, and with the superintendence of their stock during the lambing season. They considered that it matters little whether autumn-burned heather grows as well as spring- 360 THE GROUSE IN HEALTH AND IN DISEASE burned heather, the great object being to get rid of the large tracts of old useless heather which are of no value either for Grouse or sheep. They confirmed the view of the Committee that high ground with a northern exposure can only be burned in the spring in very exceptional years. The sheep-farmers further drew attention to the following points : — (1) That where heather is allowed to grow too old, there is a danger of its place being taken by bracken after burning, whereas if the heather is burned young the fresh growth has more vitality and usually defeats the bracken. (2) That old heather is undesirable because after burning many " burrens " or bare sticks are left which tear the wool off the sheep's bellies. (3) That sheep-farmers prefer the heather to be burned in large patches, because otherwise a large enough area is not burned each year ; but that they have no objection to burning in small patches and strips provided the total area burned reaches the full proportion proper to the moor. This proportion was estimated at from one-ninth to one-twelfth of the total acreage. Methods of On the actual methods of carrying out the burning there is procedure, j^^^. j^uc^ to be said. The gear is simple ; a birch broom and a paraffin firing lamp.^ The necessary party of six or eight men under a keeper can work in pairs on a calm day with a fairly dry moor, the keeper starting the fire, the couples guiding its course, extinguishing and controlling it as occasion demands. In windy weather, or when the heather gets dry, the whole party haVe to act together, and in consequence, though the individual burning may be done at a quicker rate, a smaller total area will be got through in a day. As a health-giving exercise heather-burning has much to commend it ; it is particularly hard work and trying to clothes, temper, and especially to the eyes. ' Special lamps are sold for the purpose. HEATHER-BURNING 361 Having laid down the object of heather - burning, the Practical methods of treatment of different types of ground and certain laws applicable to all moors, it only remains to discuss the practical steps the owner of a badly burned moor must take to get his heather-land into " good heart " with the least possible delay. We will presume that the moor under con- sideration is one of those many moors in England or Scotland which has possibilities, but which has been neglected ; a moor which has its high ground difficult to burn, its boggy undrained land, and its stretches of stick heather with a tendency to revert to grass ; that, moreover, it is a moor which has disease at irregular intervals as well as average and bumper years ; and that, like all moors that form part of a tract of Grouse ground, it is liable to be over-stocked at the critical period of late winter and .early spring. The first thing that the owner of a moor of this sort must Choice of ° rotation. do is to decide what rotation of heather crop is to be aimed at, i.e., what is the total area of moorland available, and how many acres of it are to be burned every year. The period of rotation requires very careful consideration, and depends on the average age of the heather, the sporting results the moor-owner wishes to obtain during the period of transition from bad conditions to good, and the local difficulties — ^labour, climate, etc. From what has been stated on the results of burning stick heather, it is evident that if really old heather bulks largely in the total area it is impracticable to jump at once into a fifteen years' rotation and maintain any stock of Grouse. A little calculation will show that in the extreme case of a moor on which all the heather has reached the " keeper's delight " stage, and therefore requires six to twenty years to come again, to burn the whole moor in fifteen years would leave not only no spring feed, but scarcely any edible heather at all. In treating a really badly burned moor, therefore, unless it is determined to sacrifice several years of sport by setting all the old heather ablaze, less heroic methods should be adopted, and the ground should be got gradually into a shortened period of 362 THE GROUSE IN HEALTH AND IN DISEASE rotation. To fix how long this intermediate period should be, it is necessary to go carefully over the burned ground of the last decade in order to see how long the general average of burned heather takes to come to maturity. This will vary, not only with the age of the heather, but with the elevation of the moor, the climate and exposure, the depth of peat, the amount of flow and hard ground, and the stock of sheep. By carefully noting the results and comparing them with similar results on well-burned moors, it will be possible to arrive at sufficient data to give the number of years for the first rotation. It is probably generally true to say that on a moor on which heather grows readily, and on which all the heather is burned before it has passed its best, heather springs from the root the year it is burned, and comes into flower sometimes in the first and generally in the second or third year. That on a badly burned moor situated 600 to 1,200 feet above sea-level the ground covered by partly withered heather of an average height of 2 feet will remain black for two years after burning, that for the next three to five years it will be covered by grass and cross- leaved heather, and that six further years will be necessary before there is a full yield of edible Calluna heather. This will mean a handicap of nine years, and on a moor of this sort a rotation of twenty to twenty-five years should, in the first case, be attempted. It must not be thought that for the whole of these nine years the ground is useless. During that period it is useful for old birds as a basking-ground, and for young chicks as a feeding-ground; and the early grasses and seeds and even ferns that grow there are not without value. It will afford, however, little or no spring food. Size of Having fixed the rotation and the acreage to be burned, P* "^ ^^' the next thing is to decide on the allocation and size of the individual patches or strips. We will suppose that the badly burned moor is one of 4,000 acres, that there is a sufficient labour supply, and that the rotation attempted is to be one of twenty years {i.e., one-twentieth of the heather ground burned per annum). The amount to be burned every year HEATHER-BURNING 363 woiild be 200 acres ; but to make up for bad burning seasons 300 acres should be attempted whenever seasonal conditions permit. To burn this area in patches of one-eighth or one-fourth of an acre is obviously impracticable ; even allowing for an area of 50 to 100 acres being burned in big blocks (flow ground or high ground with a northern exposure), it would be impossible to burn the remaining twelve hundred odd strips necessary to make up the total acreage prescribed. It is therefore necessary to decide on certain general lines of moor-burning which will give the necessary total area burned, and still maintain the patch system as far as possible. This will be obtained by treat- ing each type of heather on its own merits. 1st. To burn old heather in strips 50 yards wide, and let Example of the strip run as far as the fire will take it. 2nd. To burn average foot and a half heather in strips and patches of one fourth to one half of an acre. 3rd. To burn patches and strips on the steep faces of the wintering ground in small blocks of not more than one-fourth to one-tenth of an acre each. 4>th. To burn the burn-sides, knolls and nesting grounds of Grouse, in even smaller plots. 5th. To burn the wet flow ground in big patches of 1 to 10 acres, {N.B. — This should be done so as to cover the flow ground every six to nine years.) 6th. To burn the high ground with a northern exposure in large 3-acre blocks. 7th, To burn good broad strips round each of the boundaries. 8th. To treat specially those portions of the moor which have a tendency to revert to grass. By adopting these methods with, say, three keepers (watchers to count as keepers), each in charge of two parties of two or three men each — a total of from fifteen to twenty-one burners — it may be possible to get the work done. The burners will have to fire twenty patches of 1 to 5 acres, say a total area of 50 acres, 364 THE GROUSE IN HEALTH AND IN DISEASE Arguments against ex- tensive burning. 300 patches of from one-fourth of an acre to one acre, making, say, 150 acres, two hundred patches of from one-fourth to one- tenth of an acre, say 50 acres, i.e., about 500 bums with a total of between 250 and 300 acres. Taking the average as four parties burning a day, for it must be borne in mind that on Very dry or windy days the keepers will often have to use the whole of their posse as one burning party, it will require about ten days or twenty half days to get through the work, calculating that each party burns an average of fourteen patches a day. This is a fair statement of what ought to be done on a 4,000- acre moor ; it probably exceeds by a very considerable amount what is done on many moors of double that size. If the number of men for the burning parties cannot be got the area of the fires must be bigger ; but the ratio of heather burned to total area of the moor must be maintained at all costs. In considering the general question of heather burning, undue weight must not be attached to arguments such as the following : — (1) That the expense is too great. Apart from the question of sport, this argument can be proved to be erroneous in mere pounds, shillings, and pence, for, as has been shown already, some moors can be raised from a yield of under three hundred brace per annum to over three thousand, or, expressed in terms of existing Values, from £300 a year to not less than £3,000. Even on moors where such great advances cannot be made, the avoidance of a single year of disease would alone save more than three times the expenditure incurred in a decade through the employment of a few extra men for burning. (2) The argument that the old keeper frequently puts forward that " to strip the moor is sufficient." It is not necessary to deal with this point again ; it is sufficient here to point out that keepers have not the least idea of what acreage they burn in a year, HEATHER-BURNING 365 and will often say and believe that they burn one- tenth part of the moor when one-hundredth is nearer the mark. (3) The argument that the existing method of burning has produced good results in the past. This may be admitted, but with the reservation that good results in the past have almost invariably been followed by disease in the following year. It is to avoid disease and heighten the average yield of the moor that the progressive landlord will see that it is worth while to limit the food crop for a few years in the attempt to get the moor into good " heart." (4) The old-heather argument that it is dangerous to burn the old heather as birds will have no food in winter. Three things should be remembered in this connection. 1st. That on some of the most heavily stocked moors no old heather exists, yet there is enough winter food. 2nd. That in time of snow the medium-sized heather can be raked with little labour and thus afford abundant winter food should the moor be buried in snow, especially if the longer heather is destroyed by frost. 3rd. That long heather is valuable only as long as it gives food — Grouse eat heather shoots, not wood. Much of the heather in England and Scotland that has been left for winter food has been steadily going back for twenty years, and it now produces barely one-tenth of its proper food yield. (5) In a good burning year keepers often wish to knock off " work " under the plea that enough burning has been done for a single season. It is very doubtful if too much burning can ever be done in any season provided 366 THE GROUSE IN HEALTH AND IN DISEASE the areas of the fires are reduced in size as the patching and stripping of the moor progresses. By large fires a moor can be easily burned out, but no area of heather is so small that a smaller patch cannot be taken out of it and the moor be thereby improved. Treatment Certain moors or portions of moors have a tendency to go of crrGsii ground. back to grass, and therefore require special treatment. The most common reasons for this reversion from heather to grass is lack of attention during the period from 1850 to 1900, over- stocking by sheep (especially of the black-faced variety), and big fires after the heather has got old. In practice it is found that these causes often work in combination. The attention of gamekeepers should be directed to the burning of " white grass " as well as heather. By doing so they provide directly for the sheep and indirectly also for the Grouse ; for, so long as they are plentifully supplied with grass, sheep will not draw heavily on the heather. " White grass " can be burned in large stretches and consequently more rapidly than heather, and advantage should always be taken of any specially dry season to burn the low, damp hollows where this grass chiefly abounds ; in four seasons out of five such places are too damp to burn. To bring green ground back to heather is always a slow and often a costly business. Control of the sheep stock to prevent an over-cropping of the heather seedlings, fencing of the newly-burned patches, sowing of heather seed in specially prepared ground are all methods that may be found useful. The laisser faire argument — ^that the change from heather to grass or bracken depends on the seasons, and that nothing shoiild be done — is one that the Committee view with suspicion. Putting off burning where old heather exists only means putting off the evil day, and it is probably correct to say that for every year that the old heather is left unburned after maturity, at least one year is added to the time required for the young heather to replace the grass after burning. HEATHER-BURNING 367 There can, unfortunately, be no doubt that bracken Is Bracken, spreading considerably on very many moors in the south and west of Scotland, and that not much effort is being made to combat this pest. Thick bracken will rapidly destroy both grass and heather, but of the two it is probable that the heather will be the more easily destroyed, and if bracken has once taken possession of ground for a period of years it will be found, on clearing the ground by regular cutting, that grass will probably come where heather formerly flourished. It is a common ex- perience, when burning fairly old heather, to find that the few bracken stems which existed among the heather give rise to a much thicker crop on the bare ground, and may entirely choke the fresh growth of young heather. Despite much careful investigation by the Highland and Agricultural Society and other interested bodies, no specific has yet been discovered to cure the bracken trouble.^ It has been noticed that bracken very seldom grows on crofter " souroings " where there are many ponies. While there is not enough evidence on the subject to establish this as a solution, the fact may be worth further inquiry and experiment. In considering the general question of heather-burning, Blaeberry. blaeberry ground has been dealt with as heather ground, and its further treatment need not be gone into in any detail. It is unfortunate that sheep are specially fond of the blaeberry in its younger stages, and on moors carrying a heavy stock of sheep this valuable plant is often grazed down to the root. Grouse eat blaeberries (buds, leaves, and berries) with avidity ; even the caterpillars that infest the plant in early summer are a source of food supply for young birds. It may be noted from an examination of the tables of crop-contents that the con- sumption of blaeberry by the Grouse is irregular, and the percentage seems to depend more on the general supply of food ' Colonel 6. J. Fergu3son-Buchanau of Auchentorlie has recently printed a pamphlet setting forth the success which has attended his efforts to get rid of bracken on heather and grass land. 368 THE GROUSE IN HEALTH AND IN DISEASE than on any tendency of the birds to eat the plant more in one month than another. From statistics collected, blaeberries appear to form 30 per cent, of all the foods taken by the Grouse in Derbyshire ; 22 per cent, in Yorkshire ; and 11 per cent, in some of the counties of Scotland. Undoubtedly a good deal could be done to increase the food-yield of the moor by encouraging the growth of this hardy plant, either by fencing off areas where it is eaten down by sheep or by planting it in suitable places. Draining. Close observers of " Grouse Disease " have always held the idea that the mortality has been in some way connected with the wet, undrained portions of the moor. Scientific investigation shows that there is probably a good deal of truth in this view. The Strongyle larvae have been shown to pass the free-living portions of their lives in damp surroundings. Even in frozen water they appear to live for an indefinite period, whereas complete drought may kill them in a very short time.^ Without putting drainage forward as an absolute specific against disease, it can be urged with confidence that a well- drained moor is less liable to dangerous infection of nematode worms than a moor with stagnant pools and great stretches of flow ground. Draining should be done on a well considered plan. Nothing is more common than to see the water carefully drained from the top of a hill-face descending only to flood a much larger acreage below, owing to there being insufficient drainage arrangements for carrying off the surface water thus collected. It will generally be found advisable to employ a professional sheep-drainer, and allow him to work by contract at a fixed price per chain. The specifications must ensure that the drain is clear cut, at least the breadth of a spade at the bottom, that the sides are at a slope of not more than one in two, and 1 Vide chap. viii. pp. 234, 235. HEATHER-BURNING 369 that the turf dug out is thrown away not less than 6 feet from the drain. Shallow drains made in this way I'educe the danger to the young Grouse, and are also less liable to choke and flood the moor. Drains should be made on the herring-bone pattern, and begin with wide arms high up the hill face to catch the surface water. Special care must be taken that the central drains are sufficiently large to allow the water collected to run off easily into a main burn. The ground that it is desirable to drain is not the flat sodden bog or sour flow land, but the ground on which the fog or moss has only recently begun to choke the heather. Draining, when undertaken, should be thorough. It is better to confine the area of work and watch results, with an occasional clearing of the drains, than to spread the work over a great extent of country where little immediate result is seen, no attention is paid to upkeep, and the lie of the drains is soon lost. On most moors money would be well expended in drain- ing, for not only would the risk of infection be thereby lessened, but the total yield of heather would be increased. The supply of grit which drain-making often exposes is not a trifling con- sideration to the general health of a moor, as will be seen in chapter iii.^ ' Fide, p. 107, 2 A CHAPTER XIII THE HEATHER BEETLE Part I. — On " Frosted " Heather and its Connexion with the Heather Beetle, Lochmaea suturalis. Fob. a long time the attention of many proprietors of Grouse moors and their keepers has been directed to the fact that large patches of heather, varying in size from a few yards square to hundreds, or even thousands, of acres, have turned a rusty red or withered grey colour, and have become useless as food for Grouse. In the districts which suffered most from this condition large numbers of the Grouse have left the affected area and migrated to neighbouring moors where the heather was in a healthy state. Not only does the shooting value of such a moor become thus seriously impaired, but the health of the birds themselves is affected. Although there does not as yet appear to be any direct connexion between the diseased state of the heather and " Grouse Disease," inasmuch as the birds have been proved not to eat the withered shoots, yet the deficiency of food on an affected moor undoubtedly results in a weak state of health, rendering the Grouse less fit to resist the attacks of tape- worms and other parasites, or to combat disease of any kind whatsoever. It is, therefore, of the utmost importance to ascertain, if possible, the exact cause of this blighted condition of the heather, and to devise some practical remedy. During the progress of this Inquiry many letters have been received by the Committee which serve to show the great 370 THE HEATHER BEETLE 371 extent of heather affected in various parts of the country. Diseased heather has been reported from moors in the counties of Nairn, Perth, Inverness, Argyll, Ayr, Lanark, Kirkcudbright, Dumfries, Selkirk, Roxburgh, Fife, Cumberland, Yorkshire, and Montgomery. From this list it will be noted that the blight has been met with principally in the western districts ; but this may be due to lack of information from the east, and it is hardly safe at present to lay much stress upon the distribu- tion of " frosted " heather as indicated by this correspondence alone. Now this peculiar and serious condition of heather was, up to a comparatively recent period, universally attributed to the action of frost, whence the popular name of " frosted heather," and even at the present time this opinion is firmly maintained in some quarters. After a careful investigation of the subject we are now in a position to assert with some degree of confidence that the damage is more often the work of an insect. Attention was first drawn to the question in August 1897, when a correspondent in Ayrshire sent to Mr P. H. Grimshaw, of the Royal Scottish Museum, a patch of heather, the shoots of which were brown •and withered, while among the roots were a number of small grubs and pupae. This correspondent thought that the damage was caused by these insects, and he suggested that the diseased condition of heather which was so widely known as " frosted " was identical with that of his specimens, and due to the attack of the same species of insect. Acting upon this suggestion, Mr Grimshaw examined the soil about the roots of this sample, and of two other samples sent by the same gentleman a few days afterwards, and found therein numerous examples of the insect in all stages between that of fully-grown larva and mature insect. He identified the insect as a phytophagous beetle known as Lochmcea suturalis (Thomson), published and a short account of it, with figures.^ Little more was thought of the matter until it was again brought to notice in connection with the investigations of the > "Annals of Scottish Natmal History," January 1898, pp. 27-29. 372 THE GROUSE IN HEALTH AND IN DISEASE recent Committee. In order to obtain more evidence, either for or against the theory that the beetle was alone responsible for the damage, a circular was issued in January 1909 asking for reports from correspondents regarding the extent to which their moors had suffered from diseased heather, and requesting samples to be sent for examination. Typical examples of " frosted " heather were received from many sources, and it is important to note that in every case where the shoots had changed colour the leaves had undoubtedly been nibbled by some insect, this being easily shown by examination with a hand lens. Not only were the bases and edges of the leaves eaten, but in many cases all the leaf had disappeared except the mid-rib, which remained as a kind of bristle on the shoot. The speci- mens furnished absolute proof that the rusty red withered appearance is associated with, if not entirely due to, the attack of some insect, presumably the beetle referred to above, and which we now call the heather beetle. Method of In order to ascertain if the beetle was actually present in '°^' the samples of heather sent — not by any means an easy matter — the following plan was devised by which the little creature could be made to show itself. As all the samples were sent between the months of October and February it appeared probable that the insects, if present at all, would be in the mature stage. In all likelihood, too, they would be in a hibernating condition somewhere about the roots or surface of the soil. As it was impossible to find them without tearing to fine pieces every cubic inch of soil — a most laborious task — each block of soil, with heather attached, was soaked for several hours in water, gradually increasing the depth of the water until the actual shoots of the heather were submerged. The result was very interesting. In every case a beetle appeared a few minutes after the sod had been placed in water to be followed every few seconds by another, and so on till they had all been driven out. In this way sixteen samples of diseased heather were examined, and only two of them failed to yield specimens of the beetle ; these failures may probably be attributed to the THE HEATHER BEETLE 373 small size of the samples, for they measured only 12| and 30 square inches respectively. The following table indicates the number of beetles obtained from the samples by the above method. No. of Sample. Date. County. Size in sq. inches. No. of Beetles obtained. Remarks. 1 Oct. 13, 1908 Lanark 288 47 2 Oct. 22, 1908 Argyll 288 70 3 Jan. 26, 1909 Selkirk 144 18 4 Jan. 30, 1909 Argyll 144 23 5 Feb. 4, 1909 Ayr 60 52 6 Feb. 5, 1909 Argyll 90 48 7 Feb. 5, 1909 Ayr 64 36 8 Feb. 6, 1909 Argyll 152 3 9 Feb. 6, 1909 Cumberland 16 2 Very little soil sent. 10 Feb. 14, 1909 Argyll 112i 21 Badly diseased. 11 Feb. 14, 1909 ArgyU 72" 7 A few twigs diseased. 12 Feb. 14, 1909 Argyll 148 11 Very little diseased. 13 Feb. 15, 1909 Argyll 35 6 14 Feb. 22, 1909 ArgyU 12J Very small sample. 15 Feb. 22, 1909 Argyll 30 Very small sample. 16 Feb. 22, 1909 Argyll 72 52 Badly diseased. If these figures are worked out they show an average of Number to 1,437,480, or nearly a million and a half beetles per acre. Thus Lochmcea suturalis, if the cause of the diseased condition, is an important pest, and cannot be ignored. It may be of interest to give some further extracts from the correspondence on the subject, to show that the greater part of the evidence either actually supports, or at least is not in con- flict with the idea that the heather beetle and not frost is the agent responsible for the destruction of so many acres of heather. (a) " The enclosed . . . larvae I found yesterday on the ground amongst the grass and moss, where the heather is all dead and diseased. I thought it might be the larva of the heather beetle, so thought I would forward them to you for examination." [Contents of box were nine larvae and twelve pupae of Lochmcea.] (b) " Here we had very little signs of the insect last year, 374 THE GROUSE IN HEALTH AND IN DISEASE but this year it is over-running the moor and doing great damage. The insect made its appearance in beetle form in May, and its grubs about three weeks or a month ago, and is now to be found in hundreds on every bit of ' rusty ' and ' so-called frosted ' heather. The grub appears to appreciate [? prefer] young to old heather." (c) " From what I saw . . . about six weeks ago, I have no doubt you are correct as to ' frosted ' heather. There are great areas and many patches of this brown, withered heather on the moor, and there was a whole colony of the larvae at the roots of every such patch we looked at." (d) " My keeper has had two days on the moor, searching for the larvae or pupae of the heather beetle, and he can find none. ... I am sorry the search was not successful ; but the informa- tion that the larvae disappears between September 5th and November 5th amounts to something." (e) " On the . . . moors there were, in places, many patches of the so-called frosted heather — heather which had grown well up to a certain point, perhaps four to six years, and then without apparent rhyme or reason lost its sap and turned brown and withered before the flowering season. It looked very much like what heather might be expected to appear after a severe and late frost in May, but it was quite evident that atmospheric conditions (wind or temperature) had nothing to do with the result, as the ' frosted ' patch ended quite suddenly and was abruptly framed in perfectly sound healthy heather, which must have been exposed to exactly the same external conditions as the ' frosted ' heather. The keeper and I had many discussions over the cause of the spoilt heather, and we only agreed on one point, namely, that frost had nothing to do with the disease. I suggested a vegetable parasite, and he had views on improper burning, and there we left the matter (both of us being wide of the mark as it turned out). On ... at the time I am speaking of, there was a very considerable quantity of the ' frosted ' heather ; I couldn't, even very roughly, give the acreage, but over the .whole ground it must have mounted up to a big total, probably THE HEATHER BEETLE 375 not much less than 750-1,000 acres. The ' frosted ' heather is entirely useless for food, neither cattle, nor sheep, nor game will touch it so far as I know ; therefore in this particular year the wretched and insignificant little beetle destroyed the agri- cultural and sporting value of (?) 1,000 acres on one moderate- sized estate alone. How far the pest is spread ov^r the whole of Scotland I don't know, but the total acreage of spoilt heather must be something very big indeed, and both the farmer and the game preserver have a very troublesome enemy to cope with in Lochmcea suturalis," (/) "It may interest you to know what we have been doing about the heather beetle — practically they have damaged the whole moor, and we notice what I think was mentioned in your pamphlet, that they steadily work eastwards. We haVe been burning the affected heather as much as possible. At the time we were burning there was a very hard frost, and as regards the ground we turned up to examine we found the beetles not deep down as we expected, but clustered just round the root of the heather practically on the surface, and they didn't seem to be at all affected by the frost." {g) "I am sorry to say the heather beetle is very bad with us this year. It was seen on the wing first on April 5th in very large quantities. Now [August] the grub can be seen in the roots of the heather. The heather which was badly affected last year seems to be quite dead, and has turned white. We found in burning this spring that where the heather was burned in narrow strips the portions of heather left between were specially badly attacked, which looked as if the fire had not killed the grub, but had driven them to the heather close by. In cases where we burned one side of a knoll, we find the side left has not suffered. This may be simply a coincidence, but would appear to show that the grub can move short distances to find fresh heather to attack, but cannot move more than a few yards. With regard to stock of Grouse, we have never had such a poor show although some of the moors in this district have a fair average stock. I think we shall have to face 376 THE GROUSE IN HEALTH AND IN DISEASE burning a very large amount of the dead heather next spring." (h) "All the gamekeepers in this district obstinately main- tain that the mischief is due to frost, but none of them can account for the fact of its only appearing in patches, and not by any meatis in the most exposed places." (i) " I send you a portion of damaged heather with peat. ... My keepers here scout at the idea of beetles, and say the damage came too quickly and over too great a radius, and they consider it caused by sudden thaw on frosted heather and bleak east winds following." (j) " There was a good deal of frosted heather all over this country. In my opinion the heather beetle was not responsible for the damage, at least on my own estate. The burned patches of heather were plainly noticeable within two days of the severe frost which occurred on April 23rd, 24th, and 25th last. The heather was uninjured on dry slopes, most of the damage occurring in wet, cold, and waterlogged ground, and the patches have not extended since they were first seen. On a neighbour- ing estate I understand that the patches have been gradually extending ; but I have not verified this. I could understand the frost affecting places where the heather had already been damaged by the beetle ; but one would expect the injured por- tions to increase afterwards, and the heather to be affected on dry as well as on wet ground." (k) Same correspondent as (j). " It is very difficult for me to believe that the injury to the heather is due to the beetle, though I can well believe the beetle is a contributory cause. It is easy to find any number of beetles about the roots of the injured heather. The injured heather was all apparent immedi- ately after the frost, and has not increased during the summer. It is also in places facing the morning sun as far as we can judge. . i . In looking at the heather all over the hill there seems no place where it is quite perfect, that is to say, there always seem to be a few injured or dead shoots when one looks closely at it." {/) " You will be interested to hear there is very little to THE HEATHER BEETLE 377 be seen of the heather beetle this year, and this bears out our local experience of the pest, that after a wet winter the numbers and damage by them is very considerably checked, and that after dry winters they get bad again. This year we have had a very wet January and February, while these months in 1908 and 1909 were comparatively dry. I am Sending two samples of heather for your inspection. I am sending one of young heather, which has turned quite white and withered- looking, and is growing on the side of a hill facing the south-east. The other sample is off a large stretch of level, wet, mossy land. It seems to grow till a certain height, and then to die away." (m) " My keeper says it [i.e., diseased heather] was confined to the young heather, and the old was not frosted at all. Also the west end of the moor, about 2,000 acres, was bad with it ; and there was none on the remainder of the moor." (n) "The damage done on my own estate was not very serious, but in neighbouring places it was much worse. . . . With regard to the permanency of the damage, I do not think there is much fear. I examined some of the ground as recently as yesterday, and find that even where it has the withered grey look, the twigs are green under the bark ; only in a few cases is the previous season's growth dead, and in no case is the two-year-old growth destroyed. ... I should have stated above that the damage has only occurred where the ground was very cold, wet, and waterlogged — ^the sort of ground on which, even when drained, it is useless to plant forest trees." (o) " We think the damage is chiefly, if not entirely, confined to places where the sun strikes during the day, and especially in the morning. . . . My ground faces chiefly north-west and west." (p) " With regard to your inquiries on the subject of rusty red heather, we have noticed several small patches of this all over the moor, and the majority of them are to be seen on the south-west and south faces of the hill, and a fair amount was to be seen on the low ground at . . . This burned appearance 378 THE GROUSE IN HEALTH AND IN DISEASE first showed itself during the hot weather in the month of July, and that is the time that it is noticed each year, according to keepers and shepherds. It is, of course, useless for Grouse- feeding purposes." On referring to the foregoing extracts the reader will gather that the damage is usually noticed between the months of April and August. As will be seen later, when the life history of the beetle is dealt with, these months are exactly those in which the beetle may be presumed to be in the egg and larval stages ; fully fed larvae are to be obtained in September, while the mature beetle hibernates during the winter, and has been noted on the wing in April and May (see extracts b and g). They would presumably pair and lay eggs in one or other of these two spring months, the egg state would only occupy a few days at most, and the larva would feed during the whole of the summer months. In most cases where the diseased heather has been examined in situ the beetles or their larvae (according to the time of year) have been noted as numerous, and these observations form an interesting supplement to the figures actually obtained by experiment. Eelation to The districts from which damage from heather beetle is most commonly reported are those situated on the west coast of Scotland lying to the south of Oban. In Argyll, Ayr, Lanark, and Cumberland the pest is well known, whereas on the exten- sive moors in the northern and central Highlands of Scotland it is practically never heard of. It would appear, therefore, that the insect flourishes best in a mild climate with a high average rainfall ; but it is curious to note that after a very wet winter the beetles are not so numerous as after a dry one. With regard to the position of the ground affected there does not appear to be any rule, for the extracts show the damage to be done on slopes which face all points of the compass from north-west through west to south-east. Again, the age of the heather liable to attack appears to vary, for while some correspondents report that young heather is chiefly affected, others note the damage as done to plants of from four to six THE HEATHER BEETLE 379 years old and upwards. Most of the damaged heather occurs in patches, and there is a certain amount of evidence that low- lying wet, mossy ground is most subject to attack. This may indeed well be the case, for the beetle requires a good deal of moisture during the period of its metamorphosis from larva to mature insect, and during the course of experiments in artificial breeding of the beetle, it was found that pupse which were allowed to become dry failed to develop properly. Taking the whole of the evidence into consideration it would appear that the condition known as " frosted " heather is entirely due to the attacks of the heather beetle. The subject has been further tested by experiment. A patch of heather kept during the winter of 1908-1909 in a warm room was eaten by a number of mature beetles kept in confinement. The condition of the shoots, after being nibbled, was undistinguishable in appearance from some of the samples sent in by correspondents for examination, and in this case frost was, of course, entirely out of the question. This experience is additionally interest- ing as proving that the mature beetle, as well as the grub, feeds upon the leaves. The question of remedy alone remains for consideration ; but Eemedy for. this is a matter which presents some difficulty. It is obviously impossible to use any of the ordinary insecticides, as almost any chemical substance sufficiently poisonous to kill the grub or beetle would be dangerous to the Grouse, to say nothing of sheep. The great extent of the area to be dealt with in most cases of attack is also a serious deterrent to the use of spraying mixtures. Extensive draining of damp, mossy flats might be indirectly beneficial as a preventative of beetles, and would be directly beneficial to the moor in other respects. But draining is an expensive business, and except in districts where the ground can carry a heavy stock of Grouse, or is valuable for pasture, it may be better policy to allow the low-lying flats to remain in a water-logged condition. 380 THE GROUSE IN HEALTH AND IN DISEASE Another remedy that suggests itself as, at any rate, worth trying, is the introduction of some creature which would feed upon the beetle or its grub, and so keep its numbers in check. Unfortunately the Red Grouse itSelf does not appear to devour the insect at all, but a close relative, namely, the Black Grouse {Tetrao tetrix) has been proved to have a partiality for Lochmcea suturalis. In December, 1908, the Keeper of the Natural History Department in the Royal Scottish Museum, received for identification a small box filled with beetles. In the accom- panying letter it was stated that the beetles formed part of the contents of the crop of a Blackcock. The beetles, of which there were a great many, proved to be our old friend, or rather enemy, Lochmcea suturalis. Again, in 1907, Professor E. B. Poulton of Oxford, communicated to the Entomological Society of London an interesting account of the food of Blackgame, based upon observations made by Dr F. Menteith Ogilvie, of Oxford. In this communication Dr Ogilvie' s notes on the contents of the crops of five Blackgame are reproduced, and in four cases out of five the heather beetle had been consumed in large quantities. These notes are of so much interest in the present connexion that we cannot forbear quoting those portions which refer to the beetle. The summarised con- tents of the crops, numbered 1, 2, 4, and 5, include the following : — (1) " An immense number of small dark brown beetles, Lochmcea {Adimonia) suturalis of Thomson." (2) " Many dark brown beetles, as in ? of October 17th, 1907 [No. 1], but less numerous." (4) " Three hundred or more dark brown beetles {Lochmcea suturalis)." (5) " Immense number of the usual small dark brown beetle." " The two outstanding features are the spangle galls and the small beetle. Almost all the birds were crowded with these, and, judging by my specimens, the Blackgame must have been destroying enormous numbers of both. I don't think, as regards THE HEATHER BEETLE 381 the beetles, it is any exaggeration to allow three hundred beetles per day per bird. Ours is not a very good Blackgame ground now, and perhaps we have three hundred head in all ; that would equal ninety thousand beetles per day. I was surprised to find, too, how little heather was eaten in most cases, despite the fact that the birds were in almost every case found on the moor and not in the woods." It is interesting to note that this was written and printed before any one realised the importance of the heather beetle as a destructive insect ! Probably the only practicable method of dealing with the pest is that of burning the affected heather, not at the usual season for so doing, but at the time when the grub is on the shoots feeding. As the beetle hibernates between the months of September or October, and April or May, it would probably be of little use burning within this period, for the beetles would then be lying in a torpid condition below the surface of the soil, with cool and moist surroundings, and the flames would pass over them without doing them serious harm. The burning should, therefore, be done between May and August, when the grubs are above ground feeding on the shoots. There are two principal objections to this plan, namely the legal restrictions on heather burning in Scotland, and the practical difficulty of getting the heather to burn when in a green and sappy con- dition. A special dispensation might be obtained in order to try the effect of burning the diseased areas during the summer months. The difficulty regarding the green condition of the heather might be got over by spraying the portion to be burned with some inflammable fluid such as paraffin or petrol, in small areas at a time, and well before any light is applied. It would not be necessary for the heather itself to be so thoroughly burned as for the purpose of pro- moting young growth for feeding, the fire obtained from the inflammable agent itself might be sufficient to kill the grubs, even if the shoots did not burn so freely as at other seasons. 382 THE GROUSE IN HEALTH AND IN DISEASE Part II. — The Life History of the Heather Beetle (Lochmsea suturalis). The heather beetle {Lochmcea suturalis), whose ravages form the subject of Part I. of this chapter, is a small creature a little less than a quarter of an inch (5| mm.) in length, of an oval shape, and usually of an olive brown colour. It belongs to the family Chrysomelidse, and was first described as a distinct species in the year 1866, by the Swedish entomologist, C. G. Thomson, in his great work on the beetles of Scandinavia.^ It is very closely allied to Lochmcea caprece, Linnaeus, a species which, as its name implies, feeds on sallow {Salix caprea). From this it differs in having the forehead more shining, the little black tubercles immediately behind the bases of the feelers more distinct and polished, while the whole of the thorax is more shining. Since both species have been thoroughly de- scribed in the various works, British and Continental, which deal with Coleoptera, it is quite unnecessary to do more than refer the reader to the figure given on PI. xxii. It is interesting to note that Thomson, in his original description, says the beetle is " not rare on Salix repens and other species of willow," while Julius Weise, in his account of the Chrysomelidse in the " Natur- geschichte der Insecten Deutschlands," says it occurs " on marsh plants, also on birches and willows in marshes." Canon Fowler, on the other hand, in his " Coleoptera of the British Islands," states correctly that it is found " on heather, by no means uncommon, and very widely distributed " ; but also adds : " it also occurs on birches and willows." Our knowledge of the life history of this beetle is yet in- complete. No larvae have been seen earlier in the season than the end of August, and by this date they are practically full- grown. From this stage, however, several specimens of the mature beetle have been reared. The full-grown larva is represented in Figs. 2 and 3 of ^ " Skandinaviens Coleoptera," vol. viii. p. 151, E V/'iLson.Gam'bridge THE HEATHER BEETLE 383 PI. XXII. It measures, when straightened out, about a quarter of Larvae. an inch (6 mm.) in length, but it is usually more or less curved, and if disturbed rolls itself up close. It is of a dirty white colour, studded all over with dark markings and tubercles, which have a definite arrangement on each segment. The seg- ments themselves are transversely wrinkled, while each tubercle is tipped with a fine bristle of a pale brown colour. The dark mark- ings are arranged as follows : — ^Almost the whole upper surface of the segment immediately behind the head (that bearing the first pair of legs) is covered by a dark patch, which extends down each side to a level with the spiracles or breathing openings, and is divided down the middle by a fine line of the pale ground colour. Between this patch and the legs on either side is a small oblong dark patch two or three times as long as broad. On each of the two succeeding segments are two linear trans- verse dark marks, one anterior and the other posterior, and each divided in the middle like the patch on the first thoracic segment. On each side, opposite the extremities of each of these linear dorsal markings, is a more or less circular, but small, patch, the anterior one in each segment being smaller than the posterior ; below these, on each side, is a large dark patch of a kidney shape with the concave side uppermost, and below this again two small marks on each segment. On the dorsal surface of each of the succeeding segments are two transverse linear mark- ings, one longer at the anterior edge and the other shorter and placed at the posterior edge. Between these and the spiracles are three dark spots on each segment, one of which is anterior and in line with the longer of the linear markings, and the other two posterior and opposite the shorter. Below the spiracles a series of large more or less circular spots runs along the side of the body. The head is black and shining, and hemispherical in profile ; the legs black, with the basal joints marked with white. When the larva is about to pupate it crawls down to the Pupal stage. ground and lies amongst the moss and stems of the heather, at the same time curling itself up into a sort of horse-shoe shape. 384 THE GROUSE IN HEALTH AND IN DISEASE The anterior half of the body becomes gradually stouter, and the larva adopts the peculiar and interesting habit of suddenly straightening itself and then reassuming the horse-shoe form. In course of time, by this means, the skin of the dorsal surface of the three segments behind the head splits, and the emergence of the pupa is gradually effected by wriggling. This process, as observed by Mr Grimshaw in favourable circumstances, may be accomplished in twenty minutes, but may also take an hour or even more. The pupa, when newly emerged, is of a creamy white colour throughout, with the exception of the tiny bristles about to be mentioned, which are blackish. The characteristic form of a Chrysomelid beetle is now distinctly traceable, while the legs, wing-cases, antennae, and even mouth-parts can be recognised. Seen from above, the hemispherical thorax (prothorax of the mature beetle) occupies the most anterior portion of the body, and carries about a dozen tiny bristles, four of which form a curved row near the posterior margin, and the rest a row near the anterior margin. In a dorsal view the head is quite invisible. The meso- and meta-thoracic segments, and those of the abdo- men, are each provided with a row of four bristles, which are about equidistant from each other. Laterally, below the level of the spiracles, the abdominal segments are each tipped with a tiny bristle. Seen from beneath {see PI. xxii.. Fig. 4) the pupa shows distinctly the legs folded up close under the body, and the antennae beautifully curled under the two anterior pairs of legs and brought out again so as to show the tip of each close to the four anterior tarsi. Most of the joints of the legs may be distinctly seen, the posterior pair being folded beneath the wing-cases, which are bent round from the dorsal surface of the pupa and do not nearly reach the end of its body. The first change to be noticed in the pupa is that on the fifth day after emergence the eyes begin to change colour, assuming a pale brown tint, while a couple of days later they are of a more distinct brown, and the separate facets may be dis- tinguished. On this day also (the seventh) the extreme tips of THE HEATHER BEETLE 385 the mandibles become darkened. Six days later the eyes have become very dark brown, almost black, while the mandibles are of a rich brown tint. When two more days have elapsed, i.e., on the fifteenth day of pupal life, the tips of the mandibles are quite black, while the maxillse haVe commenced to darken at the tip. On the seventeenth day the wing-cases, legs, and antennae darken in colour, and the markings on the forehead, etc, characteristic of the mature beetle, are plainly seen, while on the eighteenth day the changes are fully accomplished, and the beetle emerges to enjoy a free and active existence. The pupal stage thus lasts, in a typical case, about three weeks. The emergence of the beetle from the pupal skin commences with the liberation of the legs from the body, and occupies, judging from an example which was carefully watched, about four hours ; but the elji;ra (wing-cases) are even at the end of that time quite pale, and only darken and harden quite gradually, assuming their permanent condition several hours later. The anterior legs and the antennae are the first appendages to become capable of free movement, while the whole of the six legs are practically free in the space of an hour. As the struggling movements proceed, it is easy to notice the extreme thinness of the enclosing pupal membrane. It is apparently of consider- able toughness, but is ultimately ruptured by the vigorous movements of the limbs. After observing the above details in the transformation of several examples, all the newly emerged beetles, together with a large number of others received from correspondents, were placed in a breeding-cage on a sod of healthy heather. In a very short time they had all disappeared, and in order to ascertain their whereabouts a small piece of the sod (about 4 inches square), was detached and torn carefully bit by bit into small fragments. It was found that in this small piece five beetles were lying in a torpid condition in little hollows immediately below the surface of the soil. When the moss, etc, was gently torn off, the beetles were betrayed by their shining elytra, as they lay back upwards. They began to move 2b 386 THE GROUSE IN HEALTH AND IN DISEASE when disturbed, and three of them got away and were recaptured. This observation tends to prove that the beetles assume the hibernating condition immediately after completing their development, which in most cases is effected by the third or fourth week of October. This date, of course, may vary slightly according to local conditions. It is a matter for regret that the life history has not been traced any further. Considerably over two hundred specimens were kept alive in cages throughout the winter of 1908, and early in the spring of 1909 (March 2nd and succeeding days), under the influence of the sunshine streaming into the room, they emerged from the soil in numbers, and became very active and excited, a few specimens indulging in short flights. Several were soon pairing ; but even with the most careful searching no eggs were discovered. Further investigation is therefore necessary before the biography of this interesting little beetle can be fully written. CHAPTER XIV KEEPERS AND KEEPERING, WITH SUB-DIVISIONS DEALING WITH POACHERS AND VERMIN It is a very common belief amongst moor-owners — ^tacitly accepted rather than openly confessed — that provided the proprietor is interested in moor management, his keenness in the shooting season, and his intermittent interference at other times of the year, wUl make up for any shortcomings on the part of his paid keeper. This is, unfortunately, very far from being the case. Great help may undoubtedly be given by advice and criti- cism, and the interest of the employer cannot fail to stimulate the keenness of the subordinate. Still the fact remains that however accurate may be the theoretical knowledge of manage- ment of the landlord, and however complete his personal atten- tion to the general principles of moor hygiene, the gamekeeper will always remain the executive officer responsible for the thousand and one details on which the health of the moor ultimately depends. In undertaking the management of shooting, it is, therefore, of primary importance not only that a good keeper should be chosen, but also that the terms of his engagement, the nature of his duties, and the extent of the assistance, both permanent and casual, to be given to him should be of such a kind as to give him the widest scope for efficient service. It is not intended in this chapter to go at length into a description of the methods of selection of a keeper, or the technical details of the duties that he should carry out after appointment. It is only proposed to suggest a few general 387 388 THE GROUSE IN HEALTH AND IN DISEASE principles founded on observations made during the course of the recent Inquiry, and shown by experience to be established on a strong and certain base. Keepers In the first place it may be stated as a universal rule, and the owner's from this there should be no departure, that the keeper should servants. j^^ ^j^^ owner's and not the tenant's servant. The reasons for this are many, and it would be hardly necessary to go into any of them were it not that this somewhat obvious precept is as often honoured in the breach as in the observance. A tenant, from the very definition of the term, is an in- dividual possessing but a temporary interest in the moor he rents. The tenant's keeper also, whose arrival and departure synchronise with the period of his master's lease, naturally looks to his immediate superior's interest rather than to the future welfare of the estate, or of those permanently connected with it. In cases of Grouse moors where the heather is well burned, where there are no troubles connected with rabbits, sheep stock, or rights-of-way, and where, broadly speaking, the interest of both contracting parties are identical, difficulties may not occur ; but this satisfactory state of affairs does not always exist. On a badly burned moor, with large tracts of rank, over- grown heather, it is difficult to see how the immediate interests of a progressive landlord and those of a shooting tenant on a short lease can ever be made to coincide. If the landlord knows his own interests, his first object must be to burn big stretches of stick heather in order to get the moor into a proper rotation of burning. The tenant, on the other hand, should he be equally well informed, knows that though such heavy burning may be beneficial to the moor in future years, the resulting crop of edible heather will not be increased during his occupancy. The keeper, therefore, who burns in the tenant's interest will burn in the smallest patches, not in order to increase the food yield so much as to provide basking ground for the old birds, and drying ground for the young chicks. He will leave severely alone the big blocks of old or dying heather, for on these KEEPERS AND KEEPERING 389 he depends for cover for the stock of birds which happen to be on the ground, their prospective food value not being his concern. This method of heather management, though suicidal, is by no means uncommon, and instances could be given in Scotland and England of magnificent moors on which no long heather is being burned, and which at the end of the current leases will show a decrease of 50 per cent, in value for many years to come. Another reason why the tenant should not directly employ the keeper is that the former is, as a rule, but an autumn visitor. Though his trust in himself be great, and his experience of shoot- ing not small, his knowledge is but too often confined to the months when the heather is in bloom, and the climatic condi- tions are at their best. He may never have visited the ground during the winter and early spring months, when the food is short, and when the results of moor management are put to the test. The tenant's knowledge of keepers and their duties is also apt to be perfunctory. A little keenness at shooting time, and a few excuses on the plea of a wet nesting season or bad weather for heather-burning, are quite enough to satisfy the average tenant that every effort has been made to get the best possible results from the moor. In this way the ineflficients escape dismissal, and the specious are awarded undeserved praise. When the keeper is the landlord's servant a very different state of things exists. In the first place, the supervision is continuous and not intermittent. In a year with a short burn- ing season, the foresters' staff, the shepherds and the labourers employed on the estate can be turned on for a few days' burning ; draining can be done under an expert sheep-drainer, and the estate personnel and organisation utilised without incurring additional expense. Again, in dealing with grazing tenants, the landlord's keeper gets more effective support from the agent, and has the minor difficulties arising from sheep gather- ings, dippings, etc., more satisfactorily settled than if the arrange- ment has to be made through a third party or by a stranger. 390 THE GROUSE IN HEALTH AND IN DISEASE Terms of service. Payment in kind not recom- mended. This question of the relations between the gamekeeper on the one hand, and the agricultural tenants and their employes on the other, is one to which it is impossible to attach too much importance. The ei^orts of the most efficient gamekeeper may be nullified by the spite of a hostile farmer or shepherd, while, should a good understanding exist, it will be found that the interests of the moor are studied by all, and that every shep- herd is a self-appointed watcher, and not infrequently the best informed man about the moor. Without dwelling further on this aspect of the question, it may be said that whether from the point of view of manage- ment, supervision, or outside help, grave risk is incurred, and no advantage gained, by the transfer of the keeper from the landlord's to the tenant's service. As to the exact terms of service, no general rules can be laid down. Wages differ in different parts of the country accord- ing to local customs, cost of living, etc. It may, however, be stated that it is a good policy to pay keepers a fair living wage, not only with a view to securing good men, but also to let them realise that their services are appreciated, and that they have a billet which it is worth their while to keep. Zeal may be further encouraged by periodically increasing the wages of a keeper who by his personal efforts has improved the value of the shooting under his charge. When this policy is adopted the criterion should be the net improvement over a term of years, and not the chance bag of one lucky season. Though the rate of wages may vary with local custom and individual largesse, there can be no doubt on one point, viz., that the emolument should be in " coin of the realm " and not in " kind." The keeper should be a keeper " first and last and all the time." In England a garden or the grazing of a couple of cows may be a desirable addition to wages ; in the Highlands a small croft may be a necessity ; but in either case agricultural enter- prise should be kept down to the margin of personal comfort, and not regarded as a substitute for wages, nor should it be KEEPERS AND KEEPERING 391 allowed to afford a separate means of livelihood. The keeper's place is on his beat, and not at the market-place watching the sale of stock. Above all things a keeper should have no interest in the sheep grazing on his beat. A man cannot serve two masters, nor should a keeper practise his retriever in herding a ewe stock, or keep his nesting ground quiet by pushing up the lately returned winter " hogs " to the high ground. Many employers prefer their keepers to be married men, and there is much to be said for the preference. A married man is less dependent upon his neighbours for society than a bachelor, and so can go about his business without attracting attention ; for the same reason it is often better for a game- keeper's house to be situated some distance away from other habitations. There is no objection to the head-keeper being a man of mature judgment and of riper years. The very fact that he has reached a time of life when he realises that he is unable to do all the work himself, will make him delegate his command, and by increased attention to his subordinates see that the work of all is efficiently carried out. For the under-keeper who has neither the grit nor the brains to climb to the top of his pro- fession a change to some low-ground beat or to the gate-keeper's lodge will often quickly repay the cost of transfer. There is some difference of opinion as to the number of Number of under-keepers required for a given area of Grouse ground, necessary. Speaking generally, many English moors, and most Scottish moors, are under-keepered. This finding may not be readily accepted by the parsimonious, but a little study of the financial aspect may bring conviction. There are many moors of 6,000 to 10,000 acres in extent with one keeper in sole charge. An area of this size cannot possibly be trapped, burned, and watched by a single man. On many such moors even one section of 1,000 acres, properly administered, may easily yield a permanent increase of one hundred brace, which, if translated into money value, would represent considerably more than the yearly wage of an under-keeper. 392 THE GROUSE IN HEALTH AND IN DISEASE Dangers of insufficient keepering. Selection of keepers. The loss arising from bad or insufficient keepering is often not fully appreciated. A very small number of stoats or hooded crows do an amount of damage which would exceed the annual cost of an extra hand. If we realise that cases can be quoted where a single pair of " hoodies " have been responsible for the destruction of a hundred eggs, or where individual foxes and peregrines have killed a score of paired birds (equivalent to the loss of fifty brace in the shooting season), it is no exaggeration to say that on good Grouse ground adequate supervision inust be obtained at any cost. It is difficult to lay down exactly the extent of ground for which an under-keeper can be responsible. This varies with the shape of the beat, the character of the ground, the stock of birds, the quantity of vermin, the amount of night watching required, and the outside duties under the keeper's charge such as rabbit-trapping, low-ground watching, fishing, etc. It may, however, be said that on a hill moor with no low ground one keeper should be able to trap, and with proper assistance to burn, from 2,000 to 4,000 acres. As to the selection of keepers some owners have a preference for dalesmen, some prefer south country Scots ; some, very rightly, have a prejudice against men who have come from a rich man's employ ; others will only take men off a moor on which a big staff of keepers is kept. It is difficult to generalise. Good men, like good horses, run in all shapes and from all countries, but it will probably be found advisable, where possible, to take a man who has been " through the mill," who has acted as a kennel-boy under a head-keeper, who is himself a good trapper and an honest man. Whatever fancies may influence the selection of the keeper the essential qualifications can readily be defined. A keeper must be a good trapper, an observer of natural conditions, and a man with the interests of the moor at heart ; above all things, he must be a worker, not a gentleman who goes to the hill with a gun. It is hardly necessary to point out that when the good man has been secured, he must be kept up to his work by periodical KEEPERS AND KEEPERING 393 inspection. A check should be kept on the amount of heather burned, the vermin hst should be frequently looked over, the number of traps actually at work should be ascertained from time to time, if necessary by surprise visits. To those acquainted with the best type of gamekeeper, it is not difficult to separate the sheep from the goats. The series of disasters which has made all heather burning impossible, the combination of chances which has prevented the traps being set on the day of the inspection, the number of vermin skins that appeared on examination to have weathered more than one winter's storms, the chance which has made the area visited the only badly burned portion of the moor, all afford reasons to show why Napoleon in his wisdom elected to employ excuse-free generals born under a fortunate star. To sum up, a sufficient number of keen young keepers, adequately paid, able to trap, willing to burn, properly supervised by a head- keeper who knows every detail of moor management, should give the required result. On small moors where only one keeper is employed, that keeper must combine the qualities of head-keeper and under- keeper ; he must have the knowledge and sense of responsibility of the former, with the capacity for hard work so important in both. Many men of this stamp are to be found, and even if at first a young keeper may be lacking in experience he will soon acquire the necessary knowledge if he is willing to learn, and if his employer is competent to instruct. Every effort should be made to foster the sense of responsi- bility in a gamekeeper. The importance of this will be admitted when it is considered that during many months of the year the keeper on a Grouse moor is out of immediate touch with his employer, and, if he chose to do so, might leave his beat to look after itself and to become a happy hunting ground for vermin and poachers. Detection of shortcomings is extremely difficult, for no master cares to spy upon his servants, and the sporting department of an estate is seldom if ever efficiently controlled from the Estate Office. Keenness is undoubtedly the basis of 394 THE GROUSE IN HEALTH AND IN DISEASE the sense of responsibility. If a keeper's whole mind is concen- trated upon how best to improve his beat very little training is required to turn him into a conscientious and responsible servant. A young keeper should be encouraged to read the best books on moor management ; he should be made to give frequent reports upon details affecting his beat, both for the employer's information and to help him to realise the many points which require attention. A keeper quickly realises that his opinions are listened to, and is thereby stimulated to experi- ment in new methods, and attempt to prove their value by definite results. The ideal It is a matter of surprise to those acquainted with sport, keeper. many of whom lead an over-busy life in our cities for the greater part of the year, what a number of capable men, intelligent, articulate, shrewd observers, not only of natural history but also of men and matters, are included m the keepers' ranks. There are few owners of moors who have not had the good fortune at one time or another to have men of this stamp in their employ- ment ; men who are friends rather than subordinates, with a frank contempt for, or rather a complete ignorance of, the ordinary conventions which restrict the intercourse between His per- class and class. Men of few words in company but with a ^°Uf power of expansion when the audience is congenial, men who are eager to learn and to accept both new views and new facts on every point connected with their profession. It is a real pleasure for any one interested in animal life to take the hill in company with a man of this sort. The habits of the dwellers of the moor, the history of the locality, old-world traditions, the beauty of the surroundings, the customs, habits and idiosyn- crasies of the visitors, are commented upon with shrewd observa- tion not unmixed with humour, the whole presented from the detached point of view of the man who is a lover of his profession, who is outside the scramble for preferment, who is satisfied with his position, and does not mean to leave it. To the really efficient head-keeper the " big shoot " comes only as the crowning circumstance of a busy year. All details KEEPERS AND KEEPERING 396 have been so carefully prepared beforehand that on the day His power itself every part of the complicated organisation falls into its tion^^^'^'^*" proper place at the proper time.^ To the master of the art the wind is always in the " airt " from which the birds can be most easily manoeuvred. Flankers appear by magic in the gully down which, for the first time in the memory of man, the birds have begun to break away. There is an order and bustle about events which acts like magic on the most dilettante breakfast-eater, which pushes on the most grasping of the guns from the " pick up " to the next row of butts, and which even stimulates the gentleman's gentle- man to take that extra bag of ammunition which is to help to create the record day. While the work is proceeding there is no bellowing of for- gotten instructions, no downward drives in which startled coveys and volleys of objurgations hurtle past alternately on a full autumn gale. Drive succeeds drive in orderly sequence. The flickering of a parti-coloured flag, quickly seen and answered by the flankers, is all that betokens the master mind. The birds rise, swing round to the downwind flankers, a sudden display of colour, and in a moment they are over the centre of the line. Little escapes the observation of such a man ; even the expert in excuses modifies his usual explanations, the most hardened cartridge burier ceases for a while from his miry operations below his butt. It is not necessary to dwell on the companion picture. The head-keeper who on the day of the shoot prepares to visit the moor for the first time, the shouting and noise which is supposed to make up for the laziness of eleven long months, the beating of dogs, the coursing of hares, the loud echoes which perplex the under-men and frighten the game, all proclaim inefiiciency and generally promise bad, certainly imenjoyable, sport. So ' While making due allowance for the high standard of intelligence required for the successful driving of Grouse it is remarkable how many gamekeepers are not naturally gifted with this particular form of genius. In nearly every case where a gamekeeper is a master of Grouse-driving his efficiency may be traced to the careful training he has received at the hands of an employer who has himself thoroughly studied the subject. 396 THE GROUSE IN HEALTH AND IN DISEASE much depends on the keeper, not only with regard to the bag to be obtained, but also with regard to the satisfaction of successful management, the pleasure and interest of well- organised shooting, that no effort should be spared to secure the suitable man. The keeper's duties in regard to vermin, poaching, control of old heather, and stock regulation are dealt with in other parts of this book.i Certain general rules of conduct are however worth noting. Principal The first rule to be laid down is that a good gamekeeper game- should never be idle. It is a fair criticism to make that laziness keepers. jg |-]^g commonest fault in gamekeepers. Also that this laziness in the majority of cases arises from ignorance and not from malice prepense. Many zealous young gamekeepers have been brought up to believe that their whole duties are to burn the heatlier in the spring, to attend upon the guns in the shooting season, and during the remainder of the year to keep their eyes open, but on no account to disturb their ground. This belief is con- venient for the idle, and had its origin no doubt from small shootings, where one man has charge of both Grouse moor and low ground. The sequence of duties on such shootings goes on without a break from heather-burning to Pheasant- rearing, and from Grouse shooting to covert shooting ; a sufficient round of activity to occupy the keeper's time through- out the year. The arrangement was probably considered satisfactory from the point of view of estate economy, even if it did not give a maximum yield of Grouse. Where a keeper has charge of Grouse ground and Grouse ground only, a higher standard should be aimed at. He must discard the old belief in an " off season," for the " off season " should be his busy time. He must overcome his dread of disturbing his ground even at the breeding season, for it is then that there is most to be learned as to the nesting capacity of his beat, and the means by which this nesting capacity ^ Vide pp. 405 et seq., 411 et seq., 343 et seq., 415 et seq. KEEPERS AND KEEPERING 397 might be improved. He will not find that the hen bird will desert merely because he happens to have located her nest, whereas if he remains at home one pair of hoodie crows may do as much harm as if he had spent a day walking over the moor and putting his foot on every clutch.^ While it may be admitted that all needless disturbance is bad it must be remembered that Nature has provided certain safeguards for the protection of the stock at the most critical period of their lives. It is almost impossible to flush Grouse at this season, and one may walk all day over a well-stocked moor without seeing any indication of the presence of birds except by their droppings. Any birds that may be flushed are usually cocks or barren pairs, and the sitting hens remain undisturbed though the intruder may pass within a few yards of them. Certain precautions must, of course, be observed, the keeper must avoid all noise, and must not return again to the spot when he has marked a sitting bird. He must creep about the moor rather than walk openly, and above all he must not be accompanied by a dog. There is a growing feeling among moor-owners that closer supervision during the nesting season is desirable, and is not necessarily followed by disastrous results. In another depart- ment of game preserving the nesting arrangements of wild birds are assisted by such plans as the so-called " Euston " or " Stetch- worth " systems, whereby the period of incubation is shortened ^ Many game preservers will challenge the foregoing remarks as contrary to all accepted theories ; but against theory can be put actual experience. One example only need be given : — On a moor which has come under the Committee's observation, where the annual bag has been known to reach the remarkable total of eighteen hundred brace off 2,000 acres of heather, the gamekeeper in charge, by close and constant attention to his duties, is able to inform his employer whether it is to be an early or late nesting year, whether the stock is large or small, whether the clutches are above or below the average, and how each beat will turn out. This information is obtained by marking any nests that may be found by chance (nests are not deliberately looked for), and by carefully observing the droppings of the "clocking " hens and the young birds. As a rule this gamekeeper and his master form a fairly accurate idea of how the season will turn out even before the dogs are run in July ; after this final test it is possible to prophesy the bag with some confidence. 398 THE GROUSE IN HEALTH AND IN DISEASE Improve- ment of nesting ground. by removing the eggs from Partridges' nests and substituting for them other eggs that have been almost hatched under a barndoor hen. The results in many places have been most successful in spite of the disturbance caused by searching for the nests and transferring the eggs.^ When the keeper has been trained in accordance with conventional doctrines his knowledge of the moor during the nesting season is often very incomplete. He conscientiously marks down some half dozen nests on the edge of the moor, and from these he judges the prospects of the whole ground. If the nests under his observation are flooded out by heavy rain, or destroyed by frost, he reports that the season will be a poor one, whereas if they hatch out successfully his hopes run high, for in his ignorance he does not take into account the distant beat which has been harried by vermin, or the waterless waste in the centre of the moor, where no wise Grouse will select its breeding ground. It must not be thought that the sole object of watching the stock during the nesting season is to form an estimate of the shooting prospects, though, as will be shown later, an early knowledge on this point is of primary importance in regulating the stock. The foregoing remaiks are intended merely to emphasise how closely a keeper may keep in touch with his duties without unduly disturbing his ground. In the per- formance of these duties many practical benefits result. The observant keeper will first of all note which areas are most favoured by nesting birds, and will try to discover what are the particular conditions which may be profitably introduced in the less favoured areas. Some of the favourable conditions may arise from the configuration of the country, a sunny ex- posure, good natural drainage, shelter from the coldest winds, etc. ; but many may be reproduced by artificial means. Natural drainage may be to some extent replaced by carefully con- structed artificial drains, the patent dew-pan may be substituted ' For a discussion of the " Stetoliworth " and other methods of Partridge preserving see Teasdale-Buokell, "The Complete Shot," pp. 246-256. KEEPERS AND KEEPERING 399 for the bum which has run dry, or a drain and conduits may be constructed to bring a copious supply of running water through the driest parts of the moor. Bad feeding may be improved by intelligent heather culture, gravel may be exposed, or heaps of broken quartz deposited, in the soft, peaty parts of the ground where there is a deficiency of grit ; and thus the nesting capacity of the moor may be extended. It may be argued that the Grouse will always prefer to nest in the places which possess the best natural conditions, and this is no doubt true ; still a season will come when a specially heavy stock has been left, and the posses- sion of a reserve of nesting ground may mean the salvation of a moor which otherwise would become overcrowded. On his visits of inspection during the nesting season the improve- keeper's hands should never be empty, and his eyes should drains and never be closed to the work to be done, the drainer's spade ^P"°ss- will be found more useful than the gun, ten minutes' work will convert a choked up spring into a clear drinking pool, the dangerous banks of steep-sided drains may be sloped away at suitable intervals, so as to make safe landing stages for any chicks that may be caught unawares by a thunder shower. The fan-shaped morass which spreads down hill from every spouting spring will be tapped at its source, and thus acres of green moss and rushes wDl be reclaimed again to heather. These will not be the only advantages gained ; every stroke of the spade will turn up the grit so often described as " the life of the moor," There is no room for vermin and an active gamekeeper on Destruo- the same beat. His constant presence drives away what he vermin. cannot destroy, or at least disturbs the raiders in the prosecution of their designs. The methods of trapping or otherwise destroy- ing vermin are dealt with in another part of this chapter, and here it is only necessary to say that whenever the keeper sees a fox or a stoat or a hooded crow upon his ground he should never rest until he has made an end of it. Every addled Grouse's egg should be given a chance of retrieving its failure by becoming the death-meal of some mountain robber. A keeper should be 400 THE GROUSE IN HEALTH AND IN DISEASE Building butts : bush- ing wire. Destruc- tion of bracken. Observa- tion of stock. Duties in the shoot- ing season. judged by the paucity of vermin to be found upon his beat, not by the total number he can kill each year. During the hatching season, and until the young birds begin to fly, the gamekeeper may continue to watch his growing stock. About this time also he may employ himself upon the building up of Grouse butts and the bushing of wire fences with bunches of heather. In June and early July much can be done to increase the heather area by the destruction of bracken, which on many moors has monopolised the sheltered glens, and is rapidly encroaching on the hill ground. Bracken can always be weakened, and sometimes eVen exterminated, if cut over twice a year in the early summer when the tender young fronds are beginning to appear above the ground, and many cases are recorded where Grouse ground has been reclaimed from this noxious weed by the energy of a determined keeper aided by a temporary staff of assistants. When the young birds begin to fly it becomes necessary for the keeper to use greater caution in his visits to the moor. He should still keep an eye upon his vermin traps, but he should not leave the roads and moorland paths more than is necessary, and he should avoid flushing the young coveys. By the end of July he may take stock of his birds with the assistance of his dogs. To ascertain what mortality has occurred since hatching he should count the young birds in every covey, and compare their average number with the average number of eggs which were successfully hatched out. If there appears to be a marked reduction he must try and discover the reason for the loss, whether vermin, climatic conditions, or disease, and if the trouble is avoidable, take measures to prevent a re- currence of the cause in the following season. With the shooting season the nature of the gamekeeper's duties become twofold. His first duty is to assist in the destruc- tion of the stock which he has fostered with such tender care, and at the same time he must keep an ever-watchful eye upon his birds with a view to the continuation of the race into future seasons. With'^^the sporting side of the question we are not KEEPERS AND KEEPERING 401 concerned, and the practice of stock regulation is dealt with elsewhere.^ But from the game-preserving point of view it is important that a note should be made of the proportion of old birds to young, of hen birds to cocks, of barren birds to the parents of broods. By a careful comparison of statistics thus collected the gamekeeper may be able to study such important problems of moor management as the following : — ^The amount of winter stock his ground will carry ; to what extent varying conditions of weather and food affect the proportion of young birds to old ; to what extent the destruction of old cocks and barren pairs influences the number of breeding pairs on his ground. In his investigations into the condition of the birds brought to bag the gamekeeper should remember that the weight of a bird is the best test of health, and he should not scorn the assistance of the spring balance. Everything possible should be done to ensure that all wounded birds are collected and put in the bag; a pricked "piner" becomes a ready victim to disease, and consequently a danger to the moor. After the regtdar shooting is over for the season the keeper Destruc- should, with the permission of the owner, do a little private q'o^°^° shooting on his own account, killing down the old cocks whenever he can, either by shooting them down in the green burns or low ground, or by stalking them round the rocky knolls. If too big a stock is left he must get the birds killed in any way that his master will allow. In September and October in England (and in November in Autumn Scotland) he will get his first chance of heather-burning, and "™"^S' thus discount the possibility of an unfavourable burning season in the spring. Doubtless during the shooting season he has marked down sundry patches of old heather which urgently require to be broken up, and he should not feel that the year has been a success unless he has at least endeavoured to reduce these patches to smaller dimensions. During the winter the keeper's work is less arduous : the Duties in stock by this time is packed and strong on the wing ; it requires ^^^ ^^' ^ Vide chap. xv. pp. 415 et seq. 2c 402 THE GROUSE IN HEALTH AND IN DISEASE little or no protection — but everything possible must be done to keep it on the ground, and if snow should cover the heather for long periods at a time, the keeper must spare no pains with rake and harrow to tide the hungry birds over the time of privation, and, if necessary, provide them with artificial food and grit. But perhaps the most important duty in the winter is that of vermin inspection. Whenever there is a fresh fall of snow the gamekeeper should be early on his beat to search for the tracks of weasels, stoats, and foxes, and thus he will gain the preliminary information necessary for the destruction of these dangerous pests. Heather- The months of February, March, and April put the same- buming. keeper's efficiency to the test, for it is principally during those months that it is his duty to provide his stock with food for future years. The good game-keeper must be a far-seeing man, who, like the forester, lives not merely for the morrow but for the day after, and he must burn his moor with a view to improved results many years ahead.^ It will be said that the various duties enumerated above repre- sent a far greater volume of work than any man can be expected to perform. It may be admitted that the average gamekeeper is not expected to do so much, but this is rather the fault of the system than of the man, for there is nothing in the foregoing list which may not be overtaken in the course of a year of three hundred and sixty-five days, for even Sundays count where game-preserving is concerned. It is true that for heather- burning, bracken-cutting, and moor-draining the keeper will require temporary assistance; but this assistance should be given ungrudgingly, for the results will yield a handsome return upon the outlay incurred. The game- Before leaving the subject it is only fair to say that srame- keeper as , , . „ , „ •> o a type. keepers as a class represent one of the finest types of the com- munity ; the healthy, open-air life they have to live seems to develop in them the primitive virtues of honesty, loyalty, and content, while the responsibility of their position leads them to ^ Vide chap, xii, pp. 343 et seq. KEEPERS AND KEEPERING 403 exercise their intellectual faculties for the furtherance of the interests committed to their charge. If they have a fault, it is an old-fashioned conservatism, tinged with professional pride, which makes them slow to adopt new ideas ; but once they have tested new methods, and found them good, all prejudice is cast to the winds, and they become ardent followers of the cause of reform. Vermin and Veemin-killing. By a misuse of the term " balance of nature " an argument The is upheld in favour of the preservation of birds and beasts that of natiu-e prey upon the Red Grouse. To speak of a restoration of the "balance of nature" as desirable for the improvement of Grouse moors is beside the point so long as the whole object of every proprietor is to upset that balance in favour of one species only. How far the destruction of all animals and birds of prey as " vermin " is reasonable, and which of them is most detrimental to a Grouse moor, are questions which should have been settled long ago, yet the discussion as to the use and abuse of vermin- killing has now continued for more than half a century, and still affords ample opportunity to gentlemen of leisure to air their views in the local press. The controversialists may be divided into two parties. The Arguments one, the more earnest and generally the more articulate, argue |Jl.^^v"in°^ that to kill vermin is to interfere with the order of creation vermin. and to upset the balance of animal life on the moor. They assert that the mortality due to " Grouse Disease " is of man's own making, because by the introduction of protective measures the weak are preserved as well as the strong, and thus the breed is allowed to deteriorate. They contend that if eagles and foxes were allowed to multiply, all the sickly Grouse would be destroyed by them, and only the fittest would survive. In the other camp may be reckoned those who believe in action rather than in argument, the moor-owner, the sportsman, 404 THE GROUSE IN HEALTH AND IN DISEASE and the gamekeeper, and it is to these that the present chapter is more specially addressed. There is no doubt that among game preservers, and more particularly amongst game- keepers, there is a tendency to destroy indiscriminately. The Committee has known a gamekeeper kill cuckoos, and receive so much a head for them from his master because they had barred feathers " like a hawk." Such a master was worthy of such a servant ! Without entering into the polemics of this well-worn con- troversy a few points not always put prominently forward may be mentioned. In the first place, it may be suggested that owing to the artificial conditions which have for years prevailed on Grouse moors the natural laws have little direct bearing on the point at issue. It is clear that if moor management has accomplished anything, we have long ago passed beyond the limit of stock that the moor would maintain if left entirely to natural conditions. It is reasonable, therefore, to argue, that if we have established and wish to preserve an unnatural stock of Grouse, we must not return to the natural state of things. The practical moor manager is not concerned with the laws of natural selection and of the survival of the fittest, but rather with the adaptation of these laws to his own special requirements. Evidence of '^^^ evidence of history affords a second and equally con- history, elusive argument against the theory that the presence of vermin is conducive to the health of the stock. Written records go to show that even in the eighteenth century, long before game preserving was introduced. Grouse were no less subject to disease than they are at the present day, in spite of the fact that their natural enemies were left undisturbed to keep the " undesir- ables " in check. As a matter of fact the whole argument is founded on an error. There is no evidence whatever that Nature's so-called scavengers confine themselves to the destruc- tion of the weaklings — ^their tendency appears to be exactly the reverse. Observation in the field goes to show that the peregrine striking at birds on the wing more often than not picks out the centre bird of the covey, and that the robber of KEEPERS AND KEEPERING 405 the hen-roost does not take the undersized piner, but the fattest bird he can find. It must, however, be admitted that the keeper who thinks Vermin sometimes his only concern is to kill all vermin indiscriminately goes equally benefldal. far towards the opposite extreme. Birds and beasts of prey are not wholly good or wholly bad ; in the destruction of mice, rats, and voles they often play a useful part, and the extermination of the greater vermin entails the duty of keeping in check the lesser pests, which tend to become too numerous owing to the destruction of their natural enemies. With these facts in view we may proceed to examine the credit and debit account of the Various animals that decorate the keepers' " dule " tree to see which should be sacrificed in the interests of sport and which should be spared. Vermin. The leading offender amongst four-footed vermin is un- Fox. doubtedly the fox — difiicult of approach, suspicious of the lure, a ranger of miles of country, one day picking a Grouse from the nest, the next day visiting the farmer's poultry yard, taking his meals sometimes off rabbits, poultry, and Grouse, sometimes off rats, voles, or even frogs, his diet must always be described as promiscuous, his morals noteworthy only by their absence. Even in his methods of destruction the fox is guided by no known law ; he will snap off the heads of a dozen fowls without carrying off a bird ; at other times he will carefully bury his victims, and as often as not fail to return to their fragrant and probably well-" trapped " remains. Stories are told of the relics of a dozen Grouse killed in the nesting season, and foTind in varying stages of decomposition in or near a fox's " earth." i It is easy to see that every effort should be made to rid the 1 In a single day's walk the Committee's field observer found three nests in which the hen Grouse had been snapped up by a fox, leaving the eggs scattered and broken, and a line of hen bird's feathers to tell the mournful tale. 406 THE GROUSE IN HEALTH AND IN DISEASE moor of an offender with such an established reputation for evil. The methods advocated for his destruction are many, including some of doubtful legitimacy in which strychnine plays a not unimportant part. Of the methods more generally recognised, " trapping " a recent kill, spooring in the snow, watching the den at cubbing time, may be enumerated. In Scotland the " fox-hunter," a gentleman clad not in scarlet but in fustian, is sometimes requisitioned with his mixed pack of lurchers, beagles, and terriers, to aid in the pursuit of his quarry ; some- times he runs the fox to earth, more often he drives him to where a confederate lies in wait to slay him with a shot gun. Foxes usually travel to a new hunting ground along certain well-defined routes, which from instinct they know to be their appointed path. Keepers are not slow to take advantage of these " trade routes." The mixed pack is laid on to the stale line of a travelling fox at dawn, and the hunters take their posts in well-known coigns of vantage, often with deadly results. Tom Speedy,! writing in "The Keeper's Book," makes many interesting remarks upon the destructiveness of foxes, and the best methods of reducing their numbers ; amongst other devices he quotes that of placing a bait on an island in a pool of water. A road or causeway is formed between the island and the mainland, and on this road a trap is carefully concealed ; he specially recommends for bait the carcass of a fox or cat. Speedy, with other authorities, draws attention to the importance of never going near the trap after it has been set lest the fox should scent the presence of man. Stoat. The stoat, next to the fox, is the most determined destroyer of game. Living in old stone dykes, disused quarries or cairns, he steals on the unsuspecting Grouse at jugging time — a short worry ensues, and a possible covey is abolished off the face of the moor. It is the habit of stoats to hunt in small packs, and when acting together, and in search of food, they are quite fearless, and will let men approach close to them before abandon- 1 F. J. Mackie, " The Keeper's Book," 7th ed., 1910: T. N. Foulis : London and Edinhurgh, pp. 107-109. KEEPERS AND KEEPERING 407 ing the chase. On one occasion the Committee's field observer saw a family of seven or eight stoats systematically hunting out a brood of young Grouse while the mother bird hovered about in a state of great anxiety, running round just out of reach, and trying to draw the marauders away from her brood. The stoat is a great traveller, and on occasions has been tracked for mDes in the snow. Like foxes, stoats seem to follow well-defined lines of migration, and cases are known where keepers have by chance struck upon these lines of march, and have been able to trap many more stoats than were ever bred on their own ground. The stoat is not, as a rule, difficult to trap. The edge of a dyke, or an opening in a wall, a narrow gully or path between rocks usually give the best results. His curiosity is often his undoing, and he is, so to speak, his own best bait. When placed in an open run the trap should be covered by a flat stone over- lying two uprights. The habit of the animal makes him wish to investigate all objects of interest without attracting attention, and often merely the satisfaction of exploring a partly concealed passage between two stones is a sufficient draw ; when the corpse of a dead brother is placed on the flat stone above, the prob- ability of a kill is greatly increased. Stoats are rarely killed down in sufficient numbers. Like every other kind of vermin they seem to congregate wherever the stock of game has begun to increase ; hardly any moor is without them, and a good keeper will kill his thirty to sixty stoats a year, and keep on doing so year in year out without apparently making any impression on the source of supply. The lazy man has one of two standard excuses which many moor-owners will recognise : on the rabbit-ridden moor — that the stoats confine their attention to ground game ; on the moor where there are no rabbits — ^that there are no stoats. No credence should be given to either statement. Every keeper should have several dozen of the best steel traps (it is useless i^ to employ any other kind) always set and left out on, the stoa,t, runs as long as they will spring. i \ r ( \ 408 THE GROUSE IN HEALTH AND IN DISEASE Weasel. Peregrine. Hooded orow. The weasel is very similar in his habits to the stoat. He also hunts in packs, but he is not quite so destructive to game, and feeds more readily on mice, moles, voles, etc. Amongst other four-footed vermin the wild cat, pole cat, hedgehog, may be mentioned ; the two first named are particu- larly destructive, but are now so rare that they may be dis- regarded by the moor-owner. The hedgehog is by no means uncommon on many moors, and is without doubt an occasional egg-stealer. The domestic cat run wild is, of course, a danger, but he is not met so frequently on the open moor as in the hedge- rows and coverts near the habitations of man. The peregrine must be bracketted equal to the fox and the hooded crow in the list of noxious vermin. He is the shyest of all the hawks, and builds in the most inaccessible places ; the quickest to kill as well as the readiest to escape with his prey. No British bird has an easier power of flight or more enjoyment in his strength ; he seems to revel in his accuracy of eye, and will strike off the head of a Grouse, pass over it, swoop again, and catch the carcass before it has reached the ground. The peregrine often kills for sport or for revenge, and will strike down an unoffending crow or jackdaw that has built too near his nest, and not even descend to see where his victim has fallen ; at other times he will hunt his terrified victim round and round a glade or corrie, striking over and under until the amusement palls. The peregrine is difficult to trap, no bait will attract him, for he scorns to touch any dead bird or beast which he has not killed himself. It cannot be argued on strictly utilitarian grounds that the peregrine has much to go down on the credit side ; when feeding his young he probably averages his brace of nesting Grouse a day, as the heaps of neatly plucked feathers left on the moor plainly testify. It is hoped, however, that owners of Grouse moors wUl always leave a few of these beautiful slate-coloured pillagers on some of the wilder and less accessible spots. For the hooded crow no plea can be made. He is not only the worst but the most widely distributed of vermin. Annually KEEPERS AND KEEPERING 409 he comes up in his hundreds from his recruiting ground by the sea, and if not watched and destroyed wUl do incalculable harm both to young birds and eggs. His reputation dates from pre- sporting days. The Celtic name of the bird is " flannag," which means " kill " or " slay." A Morayshire proverb says : " The GuUe, the Gordon and the hooded crow are the three worst things Moray ever saw." This is a high testimonial of rascality from a place known to old-time raiders as " The laich of Moray, where all men have their prey." To see the hooded crow with small beady eye hunt a hillside, drop down beside a pair of Grouse whom he suspects of having a nest, to watch his casual walk round as if merely on a tour of inspection, the fierceness with which he darts at and drives away the pair from their eggs or young, returning again and again until the last of these has been taken, leaves no thought of pity even in the most tender heart. The hooded crow usually nests in the birch woods or plantations at the edge of a moor. It is fortunately easy to kill the pair in the nesting season, and they can be trapped with bait at all times of the year. In the nesting season there is no bait like an egg, and even if the " hoodie " does not fall a victim to this bait, it may prove the death of a stoat, a rook, or some other equally objectionable scourge. Rooks are nearly as destructive as hoodies or carrion crows Rooks. on some moors, for the supply is inexhaustible, and the nests being at a distance from the moor cannot as a rule be destroyed. Jackdaws are often a serious pest upon a moor, and should Jackdaws. be kept in check with a firm hand. Their numbers can best be reduced by harrying them in the breeding season. If the old birds are kept oft their nests in frosty weather the eggs will become addled. An interesting example of the damage caused by jackdaws is furnished by a correspondent of the Committee who rents a moor in Scotland. Before he took the moor the average bag was about sixty brace, and the ground was overrun with vermin, more especially with jackdaws, which nested in the rabbit holes 410 THE GROUSE IN HEALTH AND IN DISEASE on the hillside. The tenant at once commenced to wage war against the jackdaws, and offered a sum of one half -penny an egg to any boys who robbed the nests ; in each of the last three seasons he has taken over one thousand jackdaw's eggs — one boy alone collecting upwards of five hundred ; at the end of the third season the bag had increased to over two hundred brace of Grouse, while a large breeding stock was left. The jackdaw's eggs were found very useful for feeding young pheasants. Ravens. Ravcns are already so persecuted by the shepherds that they hardly count, though there are still a fair number to be found in the remote fastnesses of the Scottish deer forests. Golden The golden eagle is too noble a bird to rank in the list of eagle. , , . . -^ vermin. He occasionally kills his Grouse on the wing, but feeds for choice on hares, with an occasional deer-calf or lamb for a change of diet. In former days, when eagles existed in large numbers in the Highlands, their depredations were so serious as materially to interfere with sheep farming. The eagle cannot be said to be a desirable recruit to the ranks of the flankers in a Grouse drive ; although he not seldom takes on himself this duty, to the rage of the keeper and bewilderment of the birds. Hawks. Of the hawk tribe all are occasionally destructive ; but it must not for a moment be supposed that all should therefore be destroyed. The kestrel or wind-hover probably does more good by killing mice and rats than he does harm by the destruction of a few young Grouse. The buzzard confines himself almost entirely to small birds, carrion, and ground game. Gulls. The greater blackback gull is destructive both to eggs and young birds, and should not be allowed to infest any moor on which it is intended to preserve a stock of Grouse. The black-headed and common gulls are destructive to eggs in certain localities ; this, however, must be regarded as the exception rather than as the rule, for Grouse frequently nest and hatch out their broods unmolested in the centre of breed- ing colonies of these birds. KEEPERS AND KEEPERING 411 Poachers. It has always been customary to divide poachers into two Two kinds classes, the professional poacher, who makes poaching a means ^°^^ ^^^' of livelihood, and the occasional poacher, who only takes game for his own consumption, or to satisfy what is called his sporting instinct — for the property of others. The professional poacher is a dangerous and undesirable The pro- member of the community, and should receive no mercy. He poacher, is generally devoid of all the finer feelings, and his sole object is to enrich himself by appropriating, in the largest possible quantities, goods that are not, his. He usually belongs to the submerged class which is recruited from the ranks of those who have gone under on account of their own shortcomings — dis- honesty, drink, or congenital laziness. In certain country towns and villages, especially those occupied by a mining or manufacturing population, poaching is not looked upon as a crime, but as a perfectly respectable and often remunerative means of occupying leisure time. Where this spirit exists the task of game preserving is a serious matter, and the preventative measures employed resemble the levee en masse rather than what might be called the keeper's " level of every day's most quiet need." Fortunately for the owners of Grouse moors it is the exception to find the professional class of poacher a very serious menace owing to the remoteness of moors from the centres of population. Nevertheless, the armed gangs do occasionally turn their atten- tion to Grouse, as may be proved by the supply of freshly killed birds that appear in the windows of the poulterers' shops on the morning of August 12th, earlier than could have been possible had they been killed in the ordinary course of sport. Systematic poaching of Grouse for the market is less common now than it was in former years. The increase in value of Grouse moors has led to more careful watching and to more severe prosecution, the proprietors in the principal game- 412 THE GROUSE IN HEALTH AND IN DISEASE preserving counties have in many cases combined together to form associations for the protection of their sporting rights, and the duty of bringing the wrongdoers to justice has been entrusted to competent men. The habits of the Grouse, too, have changed in recent years ; whether owing to the introduction of driving or because of the destruction of birds of prey, Grouse are much wilder at the beginning of the season than was formerly the case, and on many moors will not sit to dogs at all. Twenty years ago it was not uncommon for the poacher's gang to spend the nights of August 10th and 11th hunting the moors with a steady close-ranging pointer. Sometimes it is related that a lantern was suspended from the neck of the dog in order that his movements might be followed in the dark. On obtaining a point the poachers would make a detour, and would gently draw a net down wind towards the dog and drop it over the covey. These nets were sometimes captured, and may still be seen hanging as trophies on the walls of some of the shooting lodges in the North : they are beautiful pieces of workmanship, usually made of silk, very light and very strong. Snaring The Only time when Grouse still can be poached with ease is stocks, towards the end of the season, when they pack and flock to the low ground to feed on the corn stocks. On these occasions they may be snared by horsehair nooses, and there is no doubt that in certain districts this form of poaching is carried on. As the majority of " corn-feeders " are young birds, this form of poach- ing is specially harmful to a moor. There is no excuse for the gamekeeper who permits it. The cornfields to which the Grouse resort, and the hours at which they feed, are perfectly well known, and it is the duty of the gamekeeper to be constantly on the spot. The subject of poaching cannot be considered complete without some reference to the pastime of " Grouse-becking " as practised in the north of England. Becking has already been mentioned in another part of the Report,^ and the manner in which this habit of the bird has been utilised by poachers ^ Chap. i. p. 24. KEEPERS AND KEEPERING 413 is graphically described by the Rev. H. A. Macpherson in the Fur and Feather Series.^ Occasionally the professional poacher goes alone and boldly carries a gun. This method is common in the extreme north of Scotland, where the daylight is of such long duration that it is almost impossible for the gamekeepers to be always on the watch. It is a well-known fact that in flat, featureless country it is very difficult to detect a man upon the moor, or to hear the sound of a shot. All professional poaching might be prevented if the sale of Facilities game by unauthorised persons were discouraged. Game-deal- poached rouse. ing licences are granted far too often to small country trades- men, who are prepared to act as the receivers of stolen goods. This might be avoided by granting only a limited number of licences in every town, and only granting them to responsible persons. The licensed game-dealer is supposed to ascertain that the vendor had come by his game honestly, but the law in this respect is seldom enforced. The occasional poacher is a nuisance, and requires careful The watching, but it is doubtful if his depredations ever materially poacher. affect the stock upon a moor — one pair of hoodies, or the mildest attack of disease, will do more to damage the season's prospects than a score of crofters who take an odd Grouse to give a flavour to the broth. Though the occasional poacher may not do much harm he must not be encouraged — ^he disturbs the ground, and wounds more than he kills ; too often he is tempted by success to join the ranks of his professional brethren. No one can deny some measure of sympathy for the small tenant trying to earn a scanty living on a poor hill farm or croft who finds his stooks of corn in October or November black with Grouse. The crop indeed may be well-nigh worthless, but that makes the temptation all the greater to try and get some benefit out of a disastrous harvest. The landlord should deal with such cases in a broad-minded spirit, his gamekeeper 1 Pur and Feather Series, "The Grouse," pp. 65-72. 414 THE GROUSE IN HEALTH AND IN DISEASE Netting live Grouse and egg- stealing. should be instructed to assist in keeping the birds off the corn, and any old cocks that he may shoot should be given to the tenant as a solatium for damage done. One form of poaching remains to be mentioned, namely, the catching of live birds and the stealing of eggs with a view to selling them for the restocking of other ground. Catching Grouse alive is perfectly legitimate where a man nets only the birds bred upon his own moor, or on a moor which he has rented for the purpose, but in some districts in the north of England, notably in Cumberland, the practice has developed into an abuse. It is a well-known fact that certain small free- holders on the edge of the hill land who have no Grouse of their own take a heavy toll of the birds which visit their ground from neighbouring moors. ^ An example of the damage done is furnished by one of the Committee's correspondents, who writes as follows : — " Owing to the present system of netting on small holdings, Grouse preserving in Cumberland is a snare and a delusion. To give an instance— my moor in the neighbourhood of , of about 3,000 acres, used to give a yearly bag of about eight or nine hundred brace, and was worth about £500 a year to let, now two or three hundred brace, all shot in the first fortnight to save them from being caught in nets, with a rent of about £100 a year, represents the present return." The only method of checking this evil would be for purchasers to agree to boycott all sources of supply that are open to suspicion. Egg-stealing is not a very common form of poaching ; Grouse eggs travel badly, and the advantage of introducing, fresh blood by the importation of eggs has yet to be proved.^ The practical difficulties also are considerable. 1 The following passage is worth quoting : " The cause of offence may be only a tiny strip of sour pasture, heatberless, Grouseless, perhaps not worth sixpence an acre for any purpose but one. Its want of food and shelter may be so evident that birds seldom light on it, but they have to fly over it, and nets judiciously arranged and managed will, in the course of a season, capture a very large number of them, and do very great harm to the adjoining beats." G. W. Hartley, in "Victoria History of the Counties of England, Cumberland," edited by James Wilson, M.A., vol. ii. p. 439. London : Archibald Constable & Co., Ltd., 1905. Vide also Fur and Feather Series, "The Grouse," pp. 76-77. '^ Vide chap. xv. p. 446. CHAPTER XV STOCK The subject of Grouse stock management is a difficult one on The man- which to generalise, owing to the varying conditions which affect stock.^'^ the Grouse in different parts of the country. The question is, however, of so much importance that it is necessary to attempt to lay down certain rules that are generally applicable, and at the same time to note the exceptional cases to which these rules do not apply. The first question which naturally presents itself is, What The ideal is the ideal stock which good Grouse ground should be capable ® °° ' of carrying ? — in other words, how many birds can be supported upon a given area of good heather ? Simple though this problem appears, a little consideration will show that no solution can be put forward applicable to all moors. It must be remembered that the number of birds varies with the locality, the heather, the climatic conditions, and migration. Also, that even on any given moor the number is not constant, but alternates in succession with the autumn, winter, and spring seasons. Before entering into the conditions which govern and limit the number of birds, and before describing the measures which are recommended to keep the stock on a moor inside the margin of safety, it will be necessary to define the position more accurately by stating — (1) Exactly what we mean by the word " stock." (2) Certain statistics, from which broad general laws can be deduced, applicable to specific areas of moorland. 415 416 THE GROUSE IN HEALTH AND IN DISEASE Meaning of term "stock." Food con- ditions. Stock to acreage. (3) Certain facts and figures gleaned from the records of individual moors. The term " stock " is used indiscriminately to mean both the number of birds on a moor in summer when the coveys are unbroken, and the number of breeding birds which eke out a precarious living in the winter and early spring months. For the purposes of this chapter the term " stock " will be used in the latter sense only. It has been shown in previous chapters that it is in the early spring that disease invariably appears, it is therefore at that period, and the period immediately preceding it, that the question of numbers is of real significance. The reason for this is not far to seek. During the months of May, June, and Jtily the fresh young shoots of heather are probably more nourishing than at any other time of the year — even the oldest and most useless heather is not without some food value. In July, August, and September berries are added to the Grouse's diet, and in the late autumn and early winter the seed or fruit of the heather is largely eaten. In fact, it may be said that from the beginning of May to the middle of the following January the food supply, even on the worst moors, is almost inexhaustible, and during this period the ground is capable of supporting a stock far larger than it could possibly carry during the subsequent three months. If, therefore, a limit of stock is fixed for March and April, it is sufficiently plain that that limit can be carried with safety all through the year. While it is impossible to give any exact number of pairs of birds that 1,000 acres will carry in any specified district, it will probably be interesting to many of our readers to learn that, broadly speaking, the number of birds to the acre is curiously constant over wide tracts of similarly situated ground. In Yorkshire and Lancashire there are exceptional moors which carry a pair of Grouse to 2 acres ; but in the north of England, generally, one pair to 4 or 6 acres is considered a safe winter stock on fully-developed moors. In Scotland the STOCK 417 proportion is about one pair to 8 or 10 acres, except on the west coast, where the normal winter stock is often only one pair to 20, 30, or 40 acres. This generalisation can only be regarded as true of the aggregate, and not of individual moors, and it must be borne in mind that the bags obtained will show a much higher ratio. In a normal season the bag will usually be about double the numbers of the winter stock, and in a very good year it may be possible to kill as many as five birds for every nesting pair. The similarity of results obtained by a comparison of bags on great stretches of moorland enables several important deductions to be made. (1st) That there are certain natural limitations, directly connected with the growth and density of the heather crop, which local conditions of climate, soil, etc., enforce in each district. (2nd) That while close attention may modify these natural limitations, even the greatest care cannot wholly eliminate them. (3rd) That given efficient keepering and supervision, and the control both of sheep stock and shooting, the majority of what are considered third-rate moors might in time be raised to the average of the best of the simi- larly situated moors in the same district. (4th) That in any locality, owing to the slow rate at which old rank heather can be converted into good feeding, the progress of a moor from bad to good is necessarily slow. From the consideration of these generalisations we may now individual turn to the study of the following records of bags from individual ™°°''^- moors which have been selected as typical of each main tract or district. [Table P 418 THE GROUSE IN HEALTH AND IN DISEASE No. 1 No. 2 No. 3 No. 4 No. 5a No. 56 No. 6 No. 7 No. 8 No. 9 Moor. Moor. Moor. Moor. Moor. Moor. Moor. Moor. Moor. Moor. Brace 370 576 350 414 1,701 1,319 1,205 250 2,781| 316 )j 425 423 472 420 i 758i 67 784 606 444 636 183 560 4.30 2 716 474 801 913 683 J) 91 315 1,348 611 n 1,011 1,158J 1,306 1,829 1,578 )j 320 447 80 1,238 265 704^ 1,315 692 2,481 1,674 )) 660 704 259 126 810i 465 2,350J 71 4,922| 1,428 )} 880 892 411 480 1,774 382 >* * 72 4,365 885 ]) 1,214 420 728 1,247 44i 45| 973i 255 250 696 )j ... 450 1,643 480 l,26lj 886i 1,063 1,361 )) 205 780 455 1,267 232 6 476| 2,487 1,540 >j 248 1,155 60 160 600 175| 38 5,010 )) 408 1,737 175 572 154 jj 789 529 157 1,268| it 1,625 305 236 1,330 J) J) 80 180 370 617 1,309 1,567 422 476i 410 232 303 146 416 785| 1,010| 1,184 395 315j 1581 429| 528| No figures relating to the breeding stocks on these moors are available, but judging from the bags the following deduc- tions may be made : — No, 1 Moor. — Three hundred to four hundred pair of birds appears to be the limit of stock the ground would carry in March. It will be noted that every time the bag exceeds one thousand brace disaster follows. No. 2 Moor. — ^An improving moor apparently able to carry three hundred to five hundred pairs of March stock in a normal year. No. 3 Moor. — A very typical dogging moor with four hundred pairs of breeding stock a safe limit. No. 4 Moor. — A small well-burned moor — ^note the rapid recovery from disease ; also that it is dangerous to approach five hundred pairs of breeding stock. No. 5a and 5b Moors. — The records begin with the year 1866, and the disastrous character of the outbreaks in 1867 and 1873 are reflected in the bags.^ The figures in column 5a ' Fide also p. 443. STOCK 419 fluctuate so greatly from year to year that it is diificult to esti- mate a safe limit for the winter stock — probably about four hundred pairs. Column 56 represents the bags on the same moor from 1894 ; in this year driving was adopted as the only method of shooting the ground. The results of better stock regulation under the new conditions are shown by the figures. While there are no individual bags as large as in 1866 and 1872, the average bag has increased from four hundred and fifty-eight brace to seven hundred and six brace, in spite of two very bad seasons. No. 6 Moor. — A breeding stock of about six hundred brace would probably be a safe limit. No. 7 Moor. — This is a large moor extending to about 25,000 acres, and probably capable of carrying a larger stock than might be supposed from the bags ; probably one thousand five hundred pairs would not be too large a winter stock. No. 8 Moor. — Another large moor, or, strictly speaking, a collection of moors on one estate extending altogether to 34,000 acres ; about one thousand five hundred to one thousand seven hundred pairs would probably be a sufficient breeding stock, according to the condition of the heather in the early spring months. No. 9 Moor. — About five hundred to six hundred pairs. We find that on each moor so examined there is a very clearly defined limit of winter stock which it is dangerous to approach, and almost certain disaster to exceed, and that while in occasional years, owing to unusually favourable conditions, an exceptional stock of birds may be reared, there is a constant tendency for the stock to revert to the normal ratio for the district. The whole art of moor management depends upon a proper appreciation of this tendency, for if the stock be not reduced to the safety limit by artificial means, nature will inevitably intervene, and will regulate the super- abundance with such severity that it may be years before the moor recovers, 420 THE GROUSE IN HEALTH AND IN DISEASE With these considerations in view we may proceed to lay down the one great law of stock management, viz., determine the number of birds that the moor will carry safely in March, and irrespective of all other consideration kill the birds down to that limit. It is a very curious thing that while all are agreed that stock must be " hammered " in a good year, no real pre- cautions are taken either to find out when a good year is coming, or when a good year has arrived. Nothing is more common than the case of the moor - owner who, after various rumours and counter rumours, at last makes a casual inquiry about Ascot week from his agent or factor as to whether there will be any birds that shooting season. By early July he has settled his Grouse-driving parties, and has selected his shots from his regular autumn visitors, with the sole change of perhaps adding a couple of speci- ally good shots if the report is favourable, or eliminating the names of certain guests in the case of the report not being satisfactory. Towards early August he finds his way on to the moor, and the keeper, who has probably often been found fault with for undue optimism, hints vaguely that there is a " grand appearance," or perhaps, if cautious, " more than the usual stock on the ground." It is not till the first week of shooting that the host at last realises that he has got an abnormal stock of birds. His visitors rejoice, but he himself knows that his prospects of sport for future years are seriously threatened. If he realises the full significance of the position he may attempt to fit in one or two additional shooting weeks late in the season ; those who have tried to get together an October Grouse-drive will readily appreciate the difficulties of the task. Added to this he may not be favoured by fortune. The earlier shoots may be spoilt by wind or weather, the later shoots may be rendered abortive by the high gales of the equinoctial period, and by the indifferent marksmanship of a hastily collected team of guns. The result is a foregone conclusion. The moor remains insufficiently STOCK 421 shot, and by the end of the shooting season no stroke of fortune can avert the risk of disease. In the ease of the let moor in a big year the situation is even more serious. In the first place, the lessee has less favourable opportunities than the owner for obtaining information as to the prospects of the season ; in the second place, he has even less chance of killing down his stock if they are too numerous. He himself is often a fine shot ; but the same cannot always be said of his friends. The close-sitting bird of August 12th, or the reluctant " up-winder " in an evening drive, may be killed even by the novice ; but once the birds get strong on the wing, or fly with any degree of rapidity, twisting towards the spaces between the guns, rather than following an owl-like course over the centre of the butt, a very different standard of marksmanship is called for. Such birds appear to be immune from all pellets except those in the very centre of the charge. If the lessee does not succeed in thoroughly reducing his stock by early September there is little hope of much being done in the later weeks of the season ; he has probably no great acquaintance amongst the " hardy locals," and he will fail to decoy his club friends from London to drive Grouse once the Partridge season has set in. To avoid this state of things, of frequent, one might almost Early in- 1 ... i 1 i formation say regular, occurrence on many moors, it is necessary to adopt necessary. certain practical expedients. The keeper should be instructed to get about the moor in the earlier part of the nesting season, to ascertain what stock of birds is actually on the ground, and whether they are healthy ; he should mark down nests on each of the beats, and report by the middle of June how many of these nests have hatched off, and with what results. The Grouse is a particularly hardy bird, and provided that the stock is on the ground, and the eggs have hatched out, it is possible to estimate with some certainty the probable stock which will be available for sport in the shooting season. Modern methods of Partridge management require that the keeper should know not only the number of pairs on each 422 THE GROUSE IN HEALTH AND IN DISEASE beat, but even the number of eggs laid in every nest. Such accuracy is not necessary for the Grouse-keeper. He should have a rough knowledge of the number of breeding pairs on his ground, and from these, by observation of the average yield of marked nests, he should be able to give a shrewd guess as to the number of birds that should come to the gun. The result from hatchings varies much less than most people suppose. It takes a very bad year to reduce the average yield of a pair of birds below 3'5 of young brought to the gun, and only in very exceptional years does the average covey exceed 5 "2 of young birds.i Many keepers will not readily undertake the responsible duty of estimating the probable stock ; but it is not really necessary that they should do so, for, provided they can supply the facts, the proprietor may make his own deductions, and in any case it is advisable that the keeper's estimates should be checked by his master before they are acted on. While on English driving moors there is some excuse for lack of knowledge of shooting prospects, such ignorance is unpardon- able in Scotland, where the keeper can run his dogs over the moor in July. When it is certain that a good season is at hand it is probable that not only one moor will be good, but that all the neigh- bouring shootings will share in the prosperity. It is therefore advisable to pay no attention to the wise men who contend that frequent shooting will tend to drive the birds off the ground, but rather to let shooting party succeed shooting party until the stock of birds has been killed down to less than the number which is generally left on the moor. How this is to be done so as to give the best sport, and at the same time the most satisfactory results, now falls to be considered. Methods of ^o enter fully into the respective merits of shooting over Grouse.^ dogs and driving from the point of view of sport, is outside the province of this work. 1 See Table, p. 302. STOCK 423 There will always be those to whom the working of dogs, Dogging. the study of nature, the finer arts of venery, and the quiet beauties of the moor will provide two-thirds of a day's enjoy- ment. It is impossible to deny the satisfaction gained from a pair of wide-ranging dogs perfectly trained under a keeper who is thoroughly conversant with his moor, and able to take advantage of every chance of wind or change of circumstance that the day may bring forth. Although the shooting may not be difficult, the surroundings, the assistance which each sports- man is able to give in manoeuvring the Grouse, the chance shots which fall only to the alert, the feeling of satisfaction afforded by each old cock that has been outwitted, the short rests, the cool springs, and the cunning cuts from one point to another, all help to make the day's sport difficult to equal, and impossible to beat. To those who are in the first flight of shots, who love organisa- Driving. tion for its own sake, and have the latter-day mania for big bags and pleasures condensed into the shortest possible space of time, driving, on the other hand, will always claim the first place. It will be readily admitted that there are few more exhilarat- ing moments than the beginning of the down-wind drive, the first half-dozen birds neatly killed, the nearest of them lying stone dead 50 yards behind the butts, the conscious feeling of being able to deal with the situation, and the excitement of watching the big pack neatly turned by the flankers and sailing in serried mass towards the very centre of the line. While opinions differ as to the pleasure to be derived from either method of shooting, the benefits conferred by each are not hard to detail. The great advantage of shooting over dogs is that the worst shot should be able to kill without wounding. Dogging where it is possible is an excellent method of regulating the stock in a bad year. It gives an opportunity to kill all the old birds and spare the young. It is possible also to " dog " carefully the outskirts of a Grouse moor without doing any 424 THE GROUSE IN HEALTH AND IN DISEASE harm to the central beats, and thus provide a means of killing the birds on those parts of a moor which are least effectively driven. In a good year, dogging is but a very imperfect method for getting on terms with the stock. The mere fact that the coveys are large means that May, June, and July have been dry and fine, that all the birds are from first hatchings, and therefore strong on the wing, and proportionately wild. By the end of the third week of the shooting season, if the weather is fine, or earlier if August has been wet and stormy, the Grouse are nearly unapproachable, and long shots and wounded birds are the chief results of a day's outing. A further disadvantage of shooting over dogs is that single old cocks almost invariably escape. The walking powers of the parent birds of a covey are limited by the pedestrian ability of their brood, whereas the solitary old bird is subject to no such limitations. Without going into details as to how the dogging moor should be worked, certain points may be mentioned which do not always receive enough attention. In the first place it may be laid down as a rule— probably an unpalatable one — that in a bad year, when it is desirable to shoot old birds, one gun, and one gun only, should go out with each dogging party. If two guns go together the object of each shooter will be to kill outside birds so as not to interfere with his companion's sport ; if the shooter goes out alone his object is to kill the first bird on the wing, in nine cases out of ten the father of the brood. Where dogging is the usual method of shooting, the owner should work round the lower fringes of the moors towards the end of the season in order to secure as many as possible of the pricked or badly-feathered birds which have worked their way down to the grassier and wetter ground. In settled weather the high tops should also be well hunted or even stalked for the old cocks which have resorted to these supposed sanctuaries. STOCK 425 The main advantages of driving are : (1) That it affords a means by which the stock can be killed down to a proper limit ; (2) That it tends to mix the coveys, and so prevents inbreeding ; ^ (3) That as the old birds are the stronger fliers, and usually lead the packs, it is certain that in the early drives a large proportion of these elderly undesirables will be killed ; (4) That provided the host has selected his guns well the death is assured of all solitary old cocks who risk their fortune over the centre of the line. While these advantages are to be credited to driving, certain Disadvan- items have to be put down on the debit side. Unless the butts drfvfng. are occasionally changed, or the configuration of the ground makes it possible to get all the birds forward to the guns, it is certain that the birds rising nearest to the butts will be more severely shot down than those on the more distant parts of the beat. All experienced sportsmen have observed that in certain long drives, unless the wind is favourable, a large percentage of the birds first flushed escape to one flank or another, and that only a few come over the guns, while in other drives the birds are flushed from high ground, and, even if they do come forward, are secure from harm, owing to the height at which they fly. The circumstances repeat themselves each time the ground is driven, and become intensified year after year as the birds profit by experience, with the result that on every beat there are certain tracts of ground which form a sanctuary, while other tracts are overshot. It may be said that the over-shooting of certain tracts is, relatively speaking, not important, for if one portion is overshot it will quickly be restocked from the other more heavily stocked areas. It is, however, very important that no portion of a moor should be allowed to become a sanctuary, for this will lead to the survival of a race of old and useless birds, and thus reduce the annual yield of the moor. While driving is advantageous in a good year, it is a very ^ Vide note by Mr Riiiiingtou Wilson, pp. 446 et seq. 426 THE GROUSE IN HEALTH AND IN DISEASE Effect of driving on total yield. History of Grouse driving. difficult method by which to treat the stock in the years of recovery from disease. In a bad year the host and a few friends may shoot over dogs and agree only to kill old cocks ; they will be satisfied with a third of the usual bag if thereby they can bring the moor more rapidly into good order. To ask a party of guns, however, to drive Grouse, and either to refrain from shooting at the coveys, or only to pick out the old birds, is obviously impracticable. A great deal has been written, even by those in authority, to the effect that driving per se does not add to the yield of a moor. The results of observation do not support this view, and in this connexion it would not be out of place to trace the history of Grouse driving, and to study the results which have attended its introduction in different parts of the country. Grouse driving was first introduced in Yorkshire, where, owing to the wildness of the Grouse in that country, it was found difficult to obtain a satisfactory bag by any other means. Naturally the innovation resulted at first in an increased yield, and this gave rise to an exaggerated belief in the merits of driving Grouse as a means for increasing the productiveness of all moors. As a result driving was introduced on many moors where similar conditions did not exist ; in other words, when the birds were not so wild as to necessitate this method of killing them. On these moors it was found that driving did not have the same satisfactory results as in Yorkshire, and that in some districts the bags obtained by driving were actually smaller than they had been in the old dogging days. Hence there arose a school of sportsmen who condemned driving as an undesirable institution, and never ceased to lament the fact that moors which were once good dogging moors had been converted into inferior driving moors, for it is well known that once a moor has been systematically driven its value for dogging is greatly impaired. The solution of the problem is perfectly simple. On all the moors, both in England and Scotland, when Grouse were natur- ally wild, the introduction of driving was followed by an increase STOCK 427 both in the bags and in the stock, for the bags were increased owing to the increased facilities for bringing the birds to the gun, and the stock was improved owing to the possibility of killing oft the old and undesirable birds, and leaving the younger and more vigorous to form a breeding stock. But once the system of Grouse driving had been fully established the improvement came to an end. Moors whose annual yield had been improved by several hundred per cent, ceased to improve when they reached the higher level, for the beneficial results of driving had been exhausted. The question is very fully discussed by Mr Teasdale-Buckell in " The Complete Shot." This writer draws attention to a condition which he describes as one of " stagnation," which followed the establishment of Grouse driving. The stocks on many moors had been very much increased, it is true, but were no longer increasing. He quotes the figures from various moors in England in support of his argument, and gives examples of moors in Scotland which have not been improved by the introduction of driving.^ Mr Teasdale-Buckell seems inclined to think that on the whole the records do not point to any great increase of stock as a result of Grouse driving. He probably does not give sufficient weight to the cases where it v/as followed by a very marked improvement, for these cases occurred chiefly in England as long ago as 1872 and 1873. He also does not notice that while the introduction of driving in Scotland in more recent years has not had such a marked effect, it has proved an effective method of regulating the stock in " big " years, and has tended to equalise, and, in the main, to raise the average yield on those moors on which it has been given a fair trial. There can be no doubt that driving has greatly increased the stock of Grouse on practically every moor in England, as may be seen by comparison of the records before and after its introduction. On many moors in Yorkshire, where before ' "The Complete Shot," pp. 232-233. 428 THE GROUSE IN HEALTH AND IN DISEASE the days of driving Grouse had become almost extinct, they are now numerous. The beneficial effects of driving at Broomhead are fully discussed in a note by Mr Rimington Wilson, which will be found at the end of this chapter.^ Driving to be satisfactory must be efficiently carried out. It is a sine qua non that good shots must be chosen. Owing to the improvement in guns, and the amount of practice that can be obtained, few sportsmen are so inefficient as actually to miss their bird ; but there is a vast difference between the first-class shot who steadily kills four birds out of six and the indifferent performer who only wounds a similar proportion. Difficult drives — that is to say, drives in which the birds either come at a great height or dip or curve ov^er the line of butts, should be avoided unless masters of the craft are to form the firing line. Butts should not be too far apart — 40 yards is a good average distance, and if this be taken as the maximum it will obviate the necessity of firing long shots, and at the same time allow a good performer to finish off the " tailored " birds of his next-door neighbour. The butts should also, where possible, be sunk so that the birds do not see the guns, and in consequence do not alter the pace and direction of their flight. The expediency of short sky-lines, the disadvantage of having settling ground immediately in front of the butts, the proper use of " hill heads " for cornering the birds, and the general precepts for drivers, flankers, markers, pickers-up, etc., are all important, but do not fall within the immediate scope of this chapter. Though moors should be disturbed as little as possible, it is a question whether the number of driving days on some of the fashionable moors are not being unduly reduced. The rage for big shoots, and the fact that it is difficult to get good shots unless big bags can be offered, probably prevents the full development of the minor driving days whose main object is the improvement of the moor. On most moors great advantages 1 Vide p. 446. STOCK 429 would be gained by increasing the number of these minor driving days, and this might be done without disturbing the centre of the ground, for the off days might be devoted to the driving of outlying beats and high ground which at other times are never touched. If then it be admitted that, by means of driving, Grouse may be killed down to the required limit, the question arises as to the exact stock which should be left on each moor. There are certain general axioms which may be laid down Stock must with absolute confidence. The first and most important is ^^nter °" that on a badly-burned moor, where the supply of good winter deeding, feeding is small, the stock to be left on the ground for the winter must be a light one. By good winter feeding is, of course, meant the close grown six-to-ten years old heather which has already been described in an earlier chapter.^ Conversely on a moor where the heather has, by dint of severe burning, been brought into such a rotation as gives the largest possible pro- portion of winter feeding a much heavier breeding stock may be safely left. On Broomhead Moor, which may be taken as a typical Proportion example of a moor where the heather has been systematically stookto^ burned for many years past, the ground is now capable of carrying summer a large winter stock without risk. On this moor of 4,000 acres from one thousand to one thousand five hundred brace is regarded as a fair breeding stock from which to obtain a bag of three thousand brace in the following season. In estimating the number of Grouse that should be shot, the bags of previous years should be disregarded ; a moor which in the past has yielded an average bag of five hundred brace may in a big year produce one thousand five hundred brace and still be dangerously overstocked. It is the number left alive, not the number killed, that should be considered. It will be urged by many moor-owners that it is impossible Difficulties to regulate the Grouse stocks with any precision, owing to the migration, migratory habits of the birds. The objection is a pertinent ' Vide chap. iii. pp. 83 d seq. 430 THE GROUSE IN HEALTH AND IN DISEASE one, and it is this migratory habit of the Grouse which has so often defeated individual efforts at stock management. It has been pointed out in another part of the work that in many districts Grouse annually move about in large packs, often leaving the high ground for weeks, or eVen months, at a time, and congregating on the lower moors. ^ When this occurs it is obviously impossible for a moor-owner to gauge the numbers of birds belonging to his ground which still survive the shooting season, for he may either find that every bird has left the moor, or alternatively that his own home stock is largely augmented by foreign visitors. In the former case it will be impossible to reduce his stock, for the birds are no longer there to be shot ; in the latter case the packs are usually so large that any shooting that may be possible can make but little impression on the stock. The difficulty is further increased by the fact that it is usually late in the autumn before the seasonal migrations of Grouse occur, often after the close of the shooting season, when no legitimate means are available for the destruction of the birds. Owners have always been ready to admit the principle that there is danger in leaving too large a stock, and some even go so far as to put the principle into practice by instructing their gamekeepers to kill down the Grouse by systematic driving or " stooking " after the regular shooting has come to an end. This practice may result in the reduction of the stocks by a few hundred birds ; but is of little practical value unless it be carried out on a large scale throughout a wide district. Other moor-owners adopt a neutral attitude. An owner of a high-lying moor will contend that he has nothing to fear from leaving a large stock upon his ground since the birds will migrate in the autumn to lower ground, when their numbers will be reduced either by shooting or by disease, and thus the stock will be brought to reasonable dimensions before they return to breed in the spring. The answer to this argument is that if they are to be reduced by shooting it would be more ' Vide chap. i. pp. 29 et sej. STOCK 431 profitable that they should be shot by himself than that they should go to swell the bag of his neighbour ; whereas if they are destined to become the victims of disease they may never come back at all, or if they do they may return as a decimated pest-ridden stock, quite unfit for the task of reproducing their species. In the same way the owner of a low-ground moor, where the Grouse have come to winter in their thousands, sometimes argues that it matters little what number of birds may be upon his ground in the winter, since they will return to their own higher moors for the nesting season, and will leave behind them a moderate breeding stock. These owners seem to overlook the fact that the presence of an excessive stock during the winter will most probably result in wholesale mortality amongst those that are left behind, however reduced this remnant may be. The true explanation of the apathy of many moor-owners Temptation is that they have not the courage of their opinions. While large breed- admitting that in theory it is a dangerous thing to leave a big '"^ stock. stock, they know that a big stock may, under favourable conditions, result in a record bag the following year, so they take their chance, unmindful of the risk they run, with the result that a good season, which might be followed by another just as good, often becomes the starting-point of a series of disastrous years. It may be laid down as a general rule that it is better policy to aim at a high average of bags than to attempt to beat all previous records by leaving a large breeding stock. Stock regulation in a poor season is a comparatively simple Stock matter, and requires but little judgment ; no great risk is [frai! ^ incurred by leaving the stock untouched, and there is not much temptation to overshoot owing to the indifferent sport to be obtained upon an understocked moor. Sometimes, it is true, a moor may be overshot by an undesirable class of yearly tenant who is more intent upon getting value for his money than upon shooting the ground in a sportsmanlike way ; but this danger can be guarded against by a strictly-worded 432 THE GROUSE IN HEALTH AND IN DISEASE clause in the agreement. It is only in a " bumper " year that the question of stock management becomes an urgent one. In places where the migration of Grouse is the rule, efficient regulation is impossible without co-operation among proprietors. It matters little that one moor-owner should kill down his birds to the limit of safety if there are too many Grouse in the district, for other birds will crowd into his ground from adjoining moors, or his own stock may migrate for the winter to some other district where there is already an overstock. If, however, moor-owners would combine to reduce the stocks upon their individual moors the whole district would benefit. Main Each owner should make it his object to kill down his Grouse aimed at. ^ Until only an average winter stock remains. The task will not be an easy one, for in an exceptionally good season it is almost impossible to make any real impression on the stock. There is little risk of over-shooting, for eVen if a proprietor succeeds in killing every Grouse upon his ground, it is quite certain that his neighbours will not be equally successful, and by the nesting season his moor will be more than sufficiently stocked by birds which had been crowded out from elsewhere. Co-opera- The Committee suggest that where a series of moors adjoin, and where the birds by migration are common in a sense to the whole range, the proprietors, with those of the shooting tenants who grasp the stock problem, should come to an under- standing as to the best procedure for their common interests. It is suggested — Firstly. That all should agree to get full information as to the prospects of the season at the earliest possible date, either on the lines already suggested in this chapter, or by any other means that may seem best to the individual proprietors or tenants. Secondly. That at some date early in July the interested parties should meet and agree whether the year is one in which the birds should be (i.) shot in the ordinary way; (ii.) shot heavily; or (iii.) really " harried," STOCK 433 Thirdly. That arrangements should be made not only to kill down the birds on those moors where they are most plentiful, but to make a point of shooting- hard on the boundaries of moors which from slackness or bad shooting are likely to be lightly shot. Fourthly. That the local circumstances and knowledge gained from past experiences should be made known between moor and moor ; that arrangements should be made for shooting all high ground specially hard ; that " cheepers " should be universally extermin- ated ; and that the birds should be killed in October and November when they are massed on the low ground. While it is improbable that lessees could be got to combine together to shoot lightly in bad seasons, there seems no reason why they should not agree to kill the birds hard in a really good year. The majority would welcome the opportunity for making a record bag, while an increase in the number of birds killed would improve the value of the moor to the landlord. In addition to regulating the numbers of his stock the Malnten- 1 -11 T 1 • 1 1 • ance of moor-owner must also consider how the birds may be mam- health of tained in health. The practice of shooting down the stock ^ °° ^' severely whenever the birds show si^ns of disease has long been regarded as an established rule of moor management ; but it may be doubted whether the practice is justified. As a rule when birds are weak and thin at the beginning of the shooting season this is a sign that there has been an outbreak of disease in the spring ; but the birds that have survived ^jfeased the epidemic have reached the convalescent stage by August, and should be spared rather than destroyed, for they will probably be completely restored to health by November, and will be valuable as a breeding stock. This subject is fully discussed in other chapters.^ 1 l^ide chap. viii. p. 240. 2 E 434 THE GROUSE IN HEALTH AND IN DISEASE "Cheep- The case is different when the bird is weak and undersized fate Wrds. as a result of being hatched late. The common custom of sparing " cheepers " in order to give them time to develop as the season advances is one which cannot be too strongly con- demned, for it is now believed that late hatched birds are a serious menace to the health of the moor. This real menace has never been sufficiently considered, but would appear to be one of the worst consequences of the loss of first broods, the full result of which is felt far more seriously in the succeeding year than in the season when it occurs. " Cheepers " of August are seriously handicapped for the remainder of their lives. They often apparently come on quickly during the shooting season, but are lacking in bodily vigour and hardness, and compared with the birds that were hatched in May and early June they feel the pinch of winter badly. The hens, exhausted by the double moult and the trials of nesting, succumb in the succeeding spring with untold loss to the moor ; the cocks, undersized and badly nourished by the end of winter, die in still larger numbers owing to the exhaustion consequent upon their efforts to procure and to protect their mates. Late broods eventually become the most fertile soil for Strongylosis, which is always potentially dangerous even in healthy birds. This being so, it would obviously be desirable to encourage early nesting, and to save early clutches of eggs from destruction. There is, unfortunately, no possibility of encouraging birds to nest early unless by artificial feeding on a considerable scale ; but at least it is possible to avoid the loss of early nests, which is so often the result of burning too late into April. Gamekeepers sometimes speak as though no harm is done if a few early nests are burned over, and as though the second clutches of eggs were every bit as good for the moor as the first hatchings. They may be so far as the shooting of that same season is concerned — with good luck as many birds may be brought to the bag ; but for the succeeding season it STOCK 435 is likely to be the worst thing that could happen, since it breeds weakly birds that will perhaps manage to survive an open winter, only to disseminate disease in the following year, if they do not actually succumb to it themselves. There are, moreover, reasons based on actual experience Second why second clutches must always produce a smaller proportion ^°° *' of fertile eggs than first clutches. The following account comes directly from a well-known moor proprietor as to the result of hatching three clutches of eggs, each clutch consisting of the first eggs laid by three different hen Grouse. All were consecutively " fertilised " by one and the same Grouse cock. The eggs had thus every possible chance, on the mother's side, of producing the full number of healthy chicks in every sitting. The first hen having paired off with this healthy two-year-old cock Grouse, sat and hatched ten chickens out of ten eggs. A second hen then paired off with the same cock ; not immedi- ately, but some time after the first hen had begun to sit. This second hen laid eight eggs, but only four were fertile, and four chicks only appeared. The same cock again, after a similar interval, paired off with a third hen, which then laid eight eggs, but not one of them was fertile. Could there be stronger evidence for the superior value of a first clutch of eggs ? Under natural conditions the first clutch receives the full value of the cock bird with the best the hen can produce when in her best condition. Suppose that this nest is burned, or still worse, suppose that the hen has been sitting for some weeks, and is then forced to desert by stress of weather or disturbance by vermin. We have now, instead of a half-spent cock with a hen at her best, a half -spent cock with a hen already exhausted and short of her stock of subcutaneous nesting fat to the extent of several ounces. She has produced seven or eight eggs weighing an ounce apiece, and she now produces half a dozen more. Not only are these six eggs fewer in number than the first clutch, but they are almost certain to be not all fertile. And what is even worse, there is the male 436 THE GROUSE IN HEALTH AND IN DISEASE element to be considered, and if, with the best possible materials in an unspent hen, his second effort at fertilisation is 60 per cent. less efficient than his first, what will it be when he has to deal with the resources of a hen already half exhausted ? The most certain way to avoid disease is to encourage the production of strong, early, robust, well-grown, and well-fed birds that can meet and survive the privations of a hard winter, that can, if necessary, fly far afield for food, fight successfully, breed early, moult quickly, and put on new feathers without a check and without exhaustion. Such birds, if they are cocks, should weigh from 26 to 30 ounces, should have large red combs, full voices, and thick white-stockinged feet and legs ; if they are hens they should weigh up to 27 ounces, should moult rapidly and efficiently almost in mid-winter, and after hatching out their broods should be fit to moult again without still showing bare legs and weathered plumage in the shooting season. "Cheep. ^^^ *^^ other side of the question : " cheepers " too small ers." to rise twice on August 12th, hardly three parts grown when the winter is upon them, barelegged, and with a scanty growth of feathers replacing the chicken down, permanently undersized by the following spring, forced to mate with equally undersized fellows on the lower and less healthy beats where the food is soft and the water laden with the unwholesome washings of the hills around ; beaten and often killed in their fights for the more desirable mates, they are forced later on to be content with the undesirable. One can imagine such a pair losing its first nest of eggs, and attempting a second. The hen is already a confirmed " piner " exhausted by the production of half a dozen eggs. If she attempts a second brood she is likely to succumb to the intestinal parasites that infest her. At the best she appears in the August bag as a dull-feathered, shabby, undersized bird weighing 12 or 15 ounces instead of 22 or 24, or she is picked up dead with hundreds of others in April and May as a " piner " which has never bred. This is no exaggerated picture of the life of more than STOCK 437 half the birds that are sent up for examination as " found dead " or " dying " in the spring, or as having been picked out of the bag in the autumn as unfit for food, or suspected of disease. They are all alike — ^undersized, poorly feathered, desperately thin, bare-legged, and badly infested with every form of parasite within and without, and they are in consequence a very fruitful source of parasitic infection to the healthier birds around them, and a fertile soil for the cultivation and dissemination of disease. The birds referred to are definitely undersized, their bones are small and thin, their measurements are permanently below the average, they have ceased to grow as chickens when their autumn diet became a winter one, and by the end of October, instead of having enjoyed the full and varied supply of the five fattest food months of the year, they have had that of but three or four. Early hatched birds, on the other hand, are barely distin- guishable from their parents by October, or even by September, and when winter comes they are prepared to meet it. They may grow temporarily thinner with starvation, but they can never be undersized. Another question of importance in the interests of the stock is that of dealing with the old birds. The following remarks show how poor is the general opinion held concerning the value both of old cocks and of old hens. Stuart- Wortley in Fur and Feather Series writes : "It The useless- is my firm belief that the presence of these useless, and birds. it is no exaggeration to say destructive, birds (i.e., old cocks) has a great deal to do with the scarcity of broods, and the low average of stock to be found on elevated Scotch shootings. " The older birds interfere with the matrimonial arrange- ments of the younger to the prejudice of the offspring. '^ The old barren hens are bad enough, but the old cocks are the worst, and both must by some means or other be destroyed. ... I would rather poison them than have them on my own ground. 438 THE GROUSE IN HEALTH AND IN DISEASE " In the pairing season the old warriors come down from the heights, fight with and vanquish the younger ones, and absorb the young hens ; the latter lay nests full of eggs, but they are sterile, while the more youthful and capable cock bird, who would become the parent of a healthy brood, is either driven off the ground altogether or obliged to remain in a state of combative celibacy. " The old hen also, who is beyond the age of laying, attacks any young hen who may nest near her, driving her off her nest, thus causing the eggs to get cold, and the incubation to be abortive. "It is well known that in deer forests, where the great object is to get rid of Grouse, the best means to arrive at this end is to leave them alone altogether. The result is that in a great measure they die out ; or at any rate their numbers dwindle to the lowest possible point." ^ " Another trouble results from the presence of these useless old cocks, namely, over-sitting. Probably if one chicken hatches the mother leaves the rest of the eggs, and so though the brood is lost it cannot often end in the bird's death. But when a whole nestful of unfertile eggs has been laid the hen may continue to sit long after the time when a brood of chickens should have appeared, and may even be found on her eggs dead from exhaustion and disease." All the views expressed above are fully endorsed by the Committee. There is no doubt that old birds are a danger to a moor, and tend to the degeneration of the stock, for not only are they more pugnacious than the younger birds, but they do not produce such large coveys nor such robust offspring. All moor-owners who take an interest in the improvement of their stock make it a rule to ascertain as nearly as possible the proportion of young birds to old upon their ground, and whenever they succeed in reducing the proportion of old birds the stock is found to improve. One of the Committee's correspondents has made a series ' Fur and Feather Scries, "The Grouse," p. 148. STOCK 439 of observations upon a moor in Inverness-shire extending over a period of thirteen years. His analysis of the Grouse stocks and relative bags is so interesting that the Committee have obtained his permission to publish it in this wOrk as an example of how stock may be recorded for purposes of comparison. The analysis will be found on p. 440, and in the letter which accompanied it the following passages occur : — " I now enclose table showing nearly all the information I have as to old and young birds for a series of thirteen years, " As nearly as possible the moor has been shot in much the same way, and the same keeper has been in charge the whole time. " An effort has always been made to bag as many old birds as possible, both by selection and by driving all the high ground, even above the heather line. Taking the last six years, it is curious to note that whereas the state of the moor as shown by dogs prior to August 12th showed on the average 4'68 young birds in each covey, or a ratio of old to young of 100 to 234 ; the actual recorded bag during the same years showed 100 to 148. The very high proportion of old birds in the bag is, I believe, due to the following causes : — " (1) That every effort is made to select old birds in shooting. " (2) That the inspection by dogs prior to August 12th does not include all the barren pairs. " (3) That before the driving takes place the young birds particularly pack, and so escape destruction. I have often proved that many packs consist of young hens." The analysis is interesting as showing that on the moor in question a larger percentage of old birds is killed by driving than by shooting over dogs ; but as the proportion of young birds throughout the season is invariably much smaller than would be expected from the observations prior to August 12th, it is possible that the cause of this circumstance is that there has been a general migration of the young birds to lower 440 THE GROUSE IN HEALTH AND IN DISEASE Analysis op Grouse Bag fob Old and Young Birds for Thirteen Consecutive Years. Year. How Killed. n 1 ■a O Is Ratio of Old to Young. General Ratio. Total Bag. Ileinarks. Dogging Results Prior to August 12th. Coveys. Young Birds. Ratio. 1897 ( Over dogs ( Driving 1166 696 458 341 708 365 100 : 154 1 100: 105 ;■ 100 : 133 1862 No results kept 1898 ( Over dogs ( Driving 1098 764 364 310 734 454 100 : 202 1 100 : 147 1 100 : 175 1862 No results kept 1899 ( Over dogs \ Driving 966 805 417 325 649 480 100 : 132 ) 100 : 148 (■ 100 : 140 1771 No results kept 1900 ( Over dogs ( Driving 782 763 311 413 358 377 471 350 ,612 420 100 : 161 ) 100 : 85 f 100 : 114 1545 No results kept 19)1 ( Over dogs I Driving 870 807 100 : 143 ) 100 : 112 . 100 : 127 1677 128 499 2 old to 3-9 young 1902 I Over dogs ( Driving 798 412 378 275 420 137 100 : 111 ) 100: 50/ 100 : 86 1210 No results kept 1903 ( Over dogs I Driving 244 158 86 100 : 55 1 100: 65 244 "Moor covered"! with ice from 1 June 16th- f I 19th. J Nearly all barre n pairs. 1904 ; Over dogs ': Driving 651 311 272 143 379 168 100 : 139 ) 100 : 117 ) 100 : 132 962 108 455 2 old to 4-21 young 1905 1906 ( Over dogs \ Driving 758 573 277 216 481 357 100 : 174 ) 100 : 165 1 100 : 170 1331 145 793 2 old to 5-47 young ( Over dogs \ Driving 1067 896 389 319 678 477 100 : 174 1 100 : 150 ) 100 : 163 1963 244 1163 2 old to 4-77 young 1907 f Over dogs I Driving 1387 967 479 412 908 565 100 : 190 ) 100 : 135 / 100 : 164 2364 (■Very wefl < spring and V (. summer. J 299 1362 2 old to 4-65 young 1908 Over dogs ' Driving 1368 967 538 412 830 474 100 : 154 ) 100 : 115 ( 100 : 164 ) 100: 90 [ 100 : 137 2054 rSnow lay in'l { masses up till V I May. J 235 1050 2 old to 4-47 young 1909 ( Over dogi5 ( Driving 810 560 307 296 503 264 100 : 127 1370 rSnow very"! ■j late on high V 1. ground. J 142 661 2 old to 4-65 young Sinc6l904 inclusive, an attempt has been made to run the dogs over every part of the moor priOT to August 12th, and the results are registered in the last three columns of above table The exact number of barren pairs is not recorded in the figures, but all coveys areincluded' 1 oPi® ?^:?l^ ?* ^'^ '"°°'' '^ "''^""^ ^'^°° *^®* '^'""' =^^ 1«^«'. a° "A Vertebrate Fauna of Argyll and the Inner Hebrides," Edinburgh: David Douglas, 1892, pp. 155 ei seq. STOCK 445 their abode. The desire therefore to migrate, or the necessity to seek new pastures, does not exist." The same authors, in their later work on the Fauna of the Moray Basin,i refer to the danger that attends the indis- criminating introduction of new stock to a moor from a district where widely different conditions may chance to prevail. In Yorkshire, where the Grouse is not so migratory as in Scotland, a sufficient change of blood is obtained by means of driving, for the packs of young birds are constantly being moved about from one beat to another, and get no chance of staying at home on the patch of heather where they were hatched. Thus it would be almost a miracle if they were to seek out and pair with the survivors of their respective coveys, as well as being contrary to the mating instinct of all living creatures. Probably this constant mixing of the stock is one of the most beneficial results that has followed the introduction of Grouse driving, and it is principally to this that Mr Rimington WUson ascribes the large numbers and health of the birds on his Broomhead Moor, for there the Grouse do not migrate nor is fresh blood ever introduced by artificial means.^ Another method of introducing fresh blood is by changing Egg shift- the eggs in the nests. On some moors this has been successfully accomplished, and it is said that the result has been an improve- ment in the stock ; but the operation is a delicate one and entails a great deal of trouble and much disturbance of the ground. Many failures have been recorded, and the practice is not to be recommended. One great objection to the purchase of eggs or live Grouse for the purpose of improving the stock is that it encourages poaching, and it is feared that moor-owners do not always make sufficient inquiry as to whether the fresh blood purchased by them has been honestly obtained,^ ^ "A Vertebrate Fauna of the Moray Basin," Edinburgh : David Douglas, 1895, vol. ii. p. 154. 2 Vide p. '446. " ^'^A^ P- *!*• 446 THE GROUSE IN HEALTH AND IN DISEASE Hand-rear- ing. Summary. It is somewhat surprising that so little has been done in the way of stocking moors with hand-reared Grouse, for Grouse can be reared in captivity almost as easily as pheasants, and it might materially assist the restocking of a moor which had been hard hit by disease if the gamekeeper had a few coops of captive chicks, Avhich he could release as soon as they were old enough to find food for themselves. These minor expedients may on occasion prove helpful, but they are of little real importance when compared with the main rules of moor and stock management. These rules may be summarised as follows : — Ascertain the number of birds on the ground as early as possible. Determine what stock of birds can be carried with safety over the winter. Shoot early and often in a good season ; shoot old birds only in a bad season. Regulate the stock by the number to be left on the ground, and not by the bags obtained. Some Notes on Broomhead Moor by Mr R. H. Rimington Wilson. Having fortunately but little experience of epidemics on this moor, the writer can only approach the question of disease in a negative way, and try to suggest some of the conditions which may tend to make a moor comparatively free from its visits. In the first place it may be stated that there has been no serious outbreak here since 1874, but that, before this date, disease in virulent form attacked the moor on an average once every seven years. Shooting over dogs was given up about 1870, and the moor was cleared of sheep in 1877. It may here be remarked that on the first occasion on which a total of over thirteen hundred brace in a day was made on STOCK 447 this moor, the ground was carrying, roughly, a sheep to 4 acres, and this had been the case for many years. It is hardly necessary to state that the heather has been burned, and the vermin kept down in the most careful manner, and that the moor in all details has had every attention from a most keen and competent head-keeper. The condition of the moor, however, in all essentials remains the same as it has been for the last fifty years and more. The same head-keeper has had charge of it ; no fresh blood has been introduced. No drainage has been done, and practically no alterations of importance have been made. There has been only one radical innovation. Why then the comparative freedom from disease and great increase of stock on this moor ? It can hardly be attributed solely to good fortune. The writer can only conclude that the answer is to be found in the above-mentioned radical innovation — namely, the peculiar system of driving that has been in vogue here for the last thirty-five years. The driving of Grouse was of course first adopted as being the only means of making the birds accessible. It was only experience that demonstrated the vast and unexpected benefit to the health of the birds that followed its adoption. In the same way the Broomhead system of driving the birds backwards and forwards over the same set of butts was initiated as a matter of convenience and facility of transport, and with no intelligent anticipation of the results which the writer feels sure have followed, and to which reference will be made. The killing-off of the old cocks is usually put forward as the chief reason why a moor benefits from driving. No doubt their destruction is desirable, and equally so in the opinion of many is the destruction of the old hens. But this is not the main factor of improvement. The habit of the Grouse left to themselves is to remain close to their early surroundings, and to marry in their own 448 THE GROUSE IN HEALTH AND IN DISEASE families, with the natural result of decadence and a falling birth-rate. Driving upsets the family arrangements, mixes all the birds together, and produces a healthier and more prolific stock. It is often noticed that a good Grouse crop succeeds a severe winter — Nature's method of producing the same result. The severity of the winter causes the birds to shift their quarters, and the all-important crossing of the blood follows ; the possible weeding-out of the weakly birds helping the general situation. The system of driving as carried out at Broomhead — ^namely, over one set of butts — obtains to the fullest extent possible, and intensifies all the benefits to be derived from driving. The coveys pack, the packs are shuffled and reshuffled till the crossing of the blood is thoroughly ensured — ^far more thoroughly than under the usual system of driving. Nor is this the only advantage ; apart from gastronomic considerations, it will be conceded that it is of the first import- ance that the older birds should be killed and the younger left for stock. It is only the older birds that possess the necessary stamina to be so frequently on the wing and to cross the butts — as they are asked to do — six times in the day. Many of the younger birds soon tire, and finding cover and safety, live to form the nucleus of a young breeding stock. Another advantage under the above system of driving is that the pick-up of both dead and wounded is almost necessarily a very clean one To sum up, the writer believes the freedom from disease at Broomhead for the last thirty years is mainly to be attributed to the fact that the above system of driving, continued for a series of years, has produced a young stock so healthy and vigorous as to be to a great extent immune to disease. The system, in fact, automatically produces the conditions essential to a well-managed poultry farm — namely, young healthy stock and a constant change of blood. STOCK 449 This moor is divided in its lower half by a deep and wide valley, which thirty years ago the birds rarely attempted to cross. That they now require no provocation to make the passage is evidence of their higher physical condition. There is no possible doubt that their power of flight has much in- creased in the last twenty years. The system of driving over one set of butts is suitable, of course, to a very limited number of moors, and even when possible might not be adopted for reasons unnecessary to mention here. The system is mentioned solely as a possible explanation of the remarkable change that came over this moor at a time which coincided with its adoption. 2 F CHAPTER XVI GROUSE IN CAPTIVITY Observation 1n the Spring of 1906 the Committee acquired an Observation area. Area in Surrey on which experiments as to the origin of " Grouse Disease " could be carried out on healthy Grouse. The site chosen consisted of undulating hilly ground with a sandy subsoil covered with luxuriant heather, and dotted over with self-sown pine trees, very like the fringe of many Scottish moors. The special feature which made it suitable for the purposes of the Committee was the free growth of heather of the type most suitable for the food of Grouse. In order to minimise the danger arising from heather fires, the owner of the ground had wide rides cut through his heather — ^these rides are cut every spring — ^with the result that there is a luxuriant growth Of young heather every summer. This young heather provided excellent food, while the old heather at the edges of the rides made good cover for the birds during the day. Coops. In 1906 six movable coops of wire netting were made, each measuring 8 feet long by 4 feet wide, and 4 feet 6 inches in height — ^this height was essential to allow of the observers getting into the coops when it was necessary to handle the birds ; but for those who wish to try the experiment of rearing Grouse for themselves, 2 feet 6 inches or 3 feet would be an ample height. The coops were furnished with padlocked doors, and strong iron staples were driven into the ground holding the outer bar of the coop close to the ground ; this precaution is most important, for unless it is observed small vermin such as weasels and rats would get into the coops and disturb the 450 GROUSE IN CAPTIVITY 451 Grouse. Even with these precautions the Grouse on the experimental area were much disturbed by vermin, especially foxes, which abound in that part of Surrey ; these foxes came prowling round the coops when the birds were sitting, frightening them off their nests. In one case the death of a hen was attributed to a fox frightening her when on the nest, and in her frantic efforts to escape she injured herself against "the sides of the coop. Dogs also were a great trouble, disturbing the birds at all hours by day as well as by night. Each coop was furnished with a piece of tarpaulin, which could be used as a shelter from heavy rain or hot sun as required. At first the coops containing the Grouse were moved on to fresh ground every two days, being placed on the edges of the rides so as to cover about 5 or 6 feet of young heather, and 2 or 3 feet of sheltering heather ; but later, when the Grouse increased in numbers, it became impossible, on account of the labour involved, to move the coops so frequently, and it was found that moving them once a week was quite often enough. In that case, however, the birds had to be supplied with faggots or bunches of fresh heather for food at least every two days ; or, better still, every day. Later experience has shown that if these bunches of heather are tied in the coops with the tops of the heather hanging downwards the birds eat it just as well, and even better, than when thrown into the coops loose, and the heather does not become soiled by the birds standing on it. Another important point is the water supply. All drinking water must be absolutely clean, and this has been ensured as far as possible by using Hearson chicken water-fountains, which prevent the birds from soiling the water. The question of rearing Grouse on this area did not at first arise, and it was only after experience showed that such a thing was possible that the experiment was tried, and a history of the methods adopted, and the experience gained, may be of interest to our readers. 452 THE GROUSE IN HEALTH AND IN DISEASE In 1906 very few Grouse were received, and at the end of that season only four birds were left ; of these two were unfortunately killed by a fox, leaving two, a cock and a hen, which were in different coops, the hen having been used for a simple experiment. In 1907 the hen began to lay, and laid ten eggs. Then the keeper put the cock into her coop, and she laid nine more eggs, but at longer intervals between each egg ; out of these nine eggs she hatched four chickens. The remaining eggs were fertile, but after the first four were hatched she became restless and left the other eggs. Of the four chickens hatched two escaped, and the other two grew up to be about three months old, when they died. During the year 1907, thanks to the exertions of those correspondents who kindly supplied the Committee with hand- reared Grouse, far more birds were sent to the Observation Area, and owing to the fact that there was no outbreak of " Grouse Disease " that year, and that no birds were required for experimental purposes by the scientific staff, the Committee had in February 1908 twenty-seven healthy birds ; of these two were the old birds received in 1906. The remaining twenty-five birds consisted of eleven hens and fourteen cocks. Owing to the cock birds fighting, three were killed during the spring, but precautions were afterwards taken to prevent deaths from this cause. The stock had now increased to twelve pairs of birds, so it became necessary to increase the number of coops. Six more large ones were added, and six smaller ones, which have proved very useful for the segregation of the birds during the mating season, and also when the hens began to sit, for it has been noticed that when Grouse are confined in coops the cocks will not leave the hens alone on the nests, but are always driving them about ; as soon, therefore, as the hens commence to sit, it is necessary to take the cocks away and keep them in coops by themselves. This year then the Committee had twelve pairs of birds. The hens laid very well, and the experiment was tried of taking the early eggs and GROUSE IN CAPTIVITY 453 putting them under foster-mothers, but with fatal results. Two common hens of the ordinary yellow Orpington breed were set on twenty eggs each, and one on seventeen ; one hen hatched seventeen chicks and killed them all, the second hen hatched eleven and killed them all, and the third hen ate all the eggs. Ten young Grouse from late laid eggs were hatched under Grouse mothers, and successfully reared. In the spring of 1909 a healthy lot of birds were left, and after the sad experience of 1908 with foster-mothers it was decided to let the Grouse hatch their own eggs. They nested well and sat well ; but again the experiment was marred by two misfortunes. One hen was frightened by a fox, and injured herself so seriously in her efforts to escape that she was found dead in the morning, and many of the nests being on low ground were washed out and spoilt by heavy thunder- storms just as the eggs were about to hatch ; still eleven birds were hatched and successfully reared. Thus in all, up to 1909, in spite of misfortunes, twenty - three birds had been successfully hatched and reared on the experimental area. In 1908 and 1909 a number of Grouse were received from correspondents, and during both these years, and especially in 1909, a considerable number of birds were used for experimental purposes. At the end of 1909 it was found that there were more birds left on the Observation Area than the keeper could attend to. Six cocks and six hens were moved to another place where the conditions were far more artificial, yet they did fairly well. With these birds the experiment was again tried of hatching under foster-mothers, but again it was not a success ; not one chicken being reared. If foster-mothers are to be used experiment seems to show that the ordinary hen is too clumsy ; bantams might be more successful.. The Grouse remaining on the Observation Area in 1910 numbered six complete pairs and a few odd birds ; these were 454 THE GROUSE IN HEALTH AND IN DISEASE left to hatch out their own eggs, and did remarkably well. The results are shown in the following table: — Grouse Hens. No. 1 » 2 ,, 3 » 4 „ 5 No. of JEggs. No. of Chickens, 7 7 11 9 9 7 7 6 12 11 Put under a foster-mother who ate all the eggs. 14 One chicken ; other eggs not 7 . good. j Would not sit ; eggs put 4 >- under No. 5 all fertile. Hens No. 7 and 8 had one cock bird between them. No. 8 would not sit, so her eggs were put under No. 5, and all proved to be fertile, and hatched. Mating The experiment was also tried of mating one cock with exper . ^^^ hens ; this was not altogether a success. At first two hens (Nos. 7 and 8) were placed in one coop with a cock ; but it was found that this was a failure on account of the jealousy of the hens, the stronger and more pugnacious hen would never allow the other to receive any attention from the cock bird, and eventually one of the hens had to be removed. .J Another method adopted was that of placing two hens side by side in two coops, and a cock was kept with them and placed in each coop alternately for forty-eight hours. One hen laid seven eggs ; the other laid four eggs, but would not sit. The hen with seven eggs hatched one chicken ; the four eggs from the other hen were placed under another bird, and all produced chickens. Cocoidiosis, Out of the forty chickens hatched out seventeen died ; all the rest of the birds were healthy and strong. Those that died were all between four and six weeks old ; these birds were examined, and were all found to be suffering from Coccidiosis. Coccidia were chiefly found in the duodenum and blind cseca, but many of these young birds also presented symptoms of pneumonia ; in these birds coccidian oocysts were found in the trachea, the bronchi, and the bronchioles. It is quite GROUSE IN CAPTIVITY 455 possible that these coccidian cysts in the bronchioles would be capable of setting up sufficient irritation to account for the pneumonic symptoms observed in the lungs of such young birds. It would seem that Coccidiosis is the greatest danger to be found in the hand-rearing of Grouse, and the precautionary methods recommended in chapter ix. should be carefully borne in mind by those who contemplate hand-rearing on a large scale. It may be interesting to know how the Grouse were fed. Food. At first, of course, the feeding was largely experimental ; as has already been mentioned the coops were placed where the Grouse could obtain fresh heather for themselves, and it was extraordinary to see the way in which the birds ate the heather. Two birds in forty-eight hours would make the patch of heather contained within their coop appear as if it had been browsed by sheep. Later on the birds were supplied with faggots or bunches of fresh heather, and this was found to answer admirably, for at the place to which the surplus Grouse were sent in 1909 there was hardly any growing heather, and the birds were for the most part kept on bilberry patches, with a few scraps of heather. In addition to heather the birds received a mixture of grain ; at first this consisted of dharri, chicken rice, buck- wheat, and feed millet, but it was found they did not eat the two last, so latterly only dharri and chicken rice were given. Experience also shows that Grouse are very partial to fresh vegetables, especially lettuce. Attention has already been called to the necessity of a pure water supply. Another important point is grit. Grouse must have plenty of suitable grit ; the best and most natural is white quartz. The Grouse on the experimental area were always supplied with plenty of this grit, and without it they could not have been kept in health. Grit must be supplied from the earliest stage of the bird's existence ; it has been found in the gizzard of a Grouse chick not forty-eight hours old. When quite young Grouse will thrive on hard-boiled eggs and young heather, but the best food for them is fresh ants' 456 THE GROUSE IN HEALTH AND IN DISEASE " eggs " ; care must be taken not to give the ants as well as the " eggs." The method pursued on the experimental area to get rid of the ants is to put the nest in the oven for a very few minutes ; this kills the ants, but does not seem to hurt the "eggs."i The full-grown birds on the experimental area remained in splendid condition and plumage. During the four years deaths have been rare among them, and have generally been due to accident or misadventure ; the old birds of 1906 were still there in 1911, when the stock was dispersed. Some birds became wonderfully tame, while others seemed always to retain their natural wildness ; the cocks, as a rule, were bolder and became tame sooner than the hens. Most of the male birds resent any interference in their matrimonial arrangements, and their resentment is shown in many interesting ways. On approaching the coops the cocks at once begin to crow, or rather talk ; some will mount on the little faggots of heather supplied for food, and strut and talk and crow, swelling out their throats, elevating their supra-orbital combs, drooping their wings and fanning out their tails, as if defending their wives— the whole attitude denoting readiness to fight. In fact, one of the birds has been known at the mating time to follow the keeper's wife (to whom he was usually very attached), out of his pen, pecking at her as hard as he could ; while the oldest cock of all, usually quite tame, always attacked the keeper if he entered the coop when the hen was on her nest. As the birds can be observed at a very close distance the plumage can be studied, and the way in which the wings are carried, and the peculiar fan-shaped form of the tail during the courting process is well worthy of observation. Mention has been made of the necessity of constantly changing the ground on which the coops are placed ; the more often this can be done of course the better for the birds. But it is only fair to say that for the purpose of certain experiments some of the birds were kept on the same ground for months, ^ Keally the pupee of ants, popularly known as "ants' eggs." GROUSE IN CAPTIVITY 457 and it did not seem to do them the least harm ; they remained all the time in excellent health and plumage. Attention may be drawn to one very important point. It would naturally be thought that, because the climate of Surrey is warmer than that of the northern parts of the British Isles, where Grouse live in a state of Nature, the Grouse on the experimental area would nest earlier than the wild birds. The exact opposite is the rule. Every year it has been noticed that the Surrey birds lay and hatch later than Grouse in their natural state. There are several reasons to account for this. In the first place, under the conditions existing on the experi- mental area the birds are artificially and not naturally mated, and this alone may account for late nesting. It is possible, and very probable, that more extended experiments on mating hand-reared Grouse, in the same manner that Partridges are mated in captivity, might lead to earlier nesting ; but it was not possible to make this experiment on the Observation Area. Again the necessity of the constant appearance of the keeper at different times may have made the hen more shy of nesting, and the small dimensions of the coops, keeping the two birds always together, certainly is not conducive to privacy for the hen. So that those who try to keep Grouse and rear them on the lines adopted at the experimental area must not be disappointed at getting late eggs. On the other hand, the results obtained on the Surrey area show that it is within the bounds of possibility to keep Grouse in captivity, and to rear from them in such a manner as to enable owners of Grouse moors to replenish by reared birds any loss their moors may have sustained from excessive mortality in a very bad season. Since the Committee's stock of captive Grouse was dispersed, the hand-rearing experiments begun by them have been con- tinued by others with a large measure of success, and there is little doubt that it might be successfiUly developed on commercial lines. INDEX {Note : " f," " ff " = " followiug " page or pages.) AccuMATiSATioN of Grouse^ 1-2 Age of GrousBj 41 methods of ascertaining, 77 f Aleurobius farincE (flour - mite) on Grouse, 190 Alimentary tract, parasites in, l73*f Amoeba lagopodis, 203 in faeces of Grouse, 203 pathogenicity, 203 AnsBHiia, 214 Anatomy, normal, 164 BACILLUS COLI, 158, 217 ff, 221 occurring post-mortem, 158 in liver, 217 f; table, 218 not associated with mortality, 219 relation to Strongylosis, 158, 217 f „ to Coccidiosis, 266 J, to tapeworms, 200, 219 Bacteria, carried by coccidia, 256 Bantams as foster-mothers, 453 " Becking," 24, 412 Berries as food, 86 f as grit, 112 seeds as vermifuge, 112 Bill, accidental injury to, 134 Bird -lice (see Goniodes tetraonUs and Nirmus Gameratus) Blackgame, grit of. 111 accidental death, 121 remarkable series of deaths, 121 ff antagonism to Grouse, 144 heather beetle, eaten by, 380 " Blackhead," in turkeys, 267 Blaeberry, as food, 81, 86, 88, 97, 98, 367 value of, 88 f Sroportions eaten, 89 ton Abbey Moors, 333 Bones, fractured and reunited, 120 ff Bracken, 367 crofter ponies and, 367 cutting, 400 Breeding, 147 ff by last season's " cheepers," 436 loss of condition, due to, 434 Broods, early, value of, 434 danger of late, 434 diminishing value of late, 434 second, of small value, 435 experiments, 435 Broomhead Moors, 335, 446 f effects of " driving" at, 446 f breeding stock at, 429 notes on, by R. H. Rimingtou Wilson, 446 f " Bumblefoot " in Grouse, 137 "Bushing" offences, 400 Butts, distance apart, 428 Buzzard, not destructive to Grouse, 410 Cjecum, 168, 169, 175, 190 importance of, 171 Trichostrongylus in, 173, 175 normal, described, 169 diseased, described, 214 ff csecal excreta, 171, 188 Capercailzie, antagonism to Grouse, 145 Carron Moor, 337 Cat, wild, 408 domestic, 408 Catechu, a specific in Coccidiosis, 268 Cawdor Moor, 341 Oeratophyllus gallinulcB, 185 „ garei, 186 Cestodes, 192 ff chemical reaction of media necessary to, 168 not a cause of " Disease," 167 459 460 INDEX Cestodes — continued. intermediate hosts unknown, 193 development of, 192 S " Cheepers " and late hirds, 434 if should be killed out, 434 liable to "Disease," 436 f fate of, 436 f Claws, as guide to age, 77 Claw-shedding, 77 Cloudberry as food, 98 Cobbold's theory of " Grouse Disease," 163 ff Coccidiosis, 246 if may occur in man, 248 in rabbits, 247, 255 aiFects all birds, 248, 271 f in turkeys — ■" blackhead," 269 in Grouse, 246 ff rarely fatal to adults, 246, 257, 268 fatal to chicks, 18 f, 204, 257, 262, 299 affecting liver, 266 duodenal, 255 typhlitic, 255 confined to digestive tract, 204, 265 accompanied by anaemia, 253, 254 symptoms, 263 effect on weight, 256 „ on appearance, 264 f in hand-reared Grouse, 464 infection, artificial, 268 „ natural (by water), 258 associated with bacterial infection, 266 leucocytosis in, 256 dissemination by insects, 204, 258 „ by birds, 270 „ in dry weather, 268, 297 ff preventive measures, 265, 267 burning dead bodies, 268 heather-burning, 265 sanitary precautions, 268 ff treatment, 270 catechu, 270 Coccidium (Eimeria) avium, 204, 247 ff habitat, 204 life history, 248 morphology, 248 ff sporozoite stage, 248, 262 trophozoite stage, 248 schizogony, 248 merozoites, 249 gametogony, 249 encystment, 249 sexual differentiation, 249 Ooccidium — continued. fertilisation, 262 periodicity, 252 sporogony, 252 onset means recovery or death of host, 257 oocysts, vitality of, 269, 260 effect of moisture on, 269 „ of drying on, 261 reagents destructive to, 266 effect on host, 262 f „ on weight of Grouse, 263, 264 as inseminating bacteria, 266 insect carriers of, 204 Cocks, old, killing, dovni, 401 uselessness of, 437 f Collision with wire, 119 Conditions, local, affecting Grouse, 273 course of investigation, 322 Corn feeding, 29, 95, 145, 332 relation to disease, 146, 178 ff, 332 injury from, 96 f unusual effect on blackgame, 121 ff poaching and, 412 Cranberry as food, 98 Crop, 165 never contains water, 106, 166 accidental injury to, 127, 134 f shot pellets in 135 Crop contents, 79 ft' weight of, 79 table of weights, 80 table of monthly averages, 82, 89 chart of percentages of foods, 93 of Willow Grouse, 144 of Blackgame, 380 Crossing of blood, 441 ff Crow, as vermin, 408 f Crowberry as food, 99 DAVAINEA CESTICILLUS, 199 rare in Grouse, 199 intermediate host, 199 Davainea urogaUi (Large Tapeworm), 197 effect on host, 176 habitat, small intestine, 168, 176, 198 and bacterial infection, 219 morphology, 198 intermediate host not discovered, 194 ff Dew, 107 Dew-pans, 339 Diarrhoea, " white," 271 Digestion, process of, 81, 166 f chemical reactions in, 168 f Diptera, parasitic, 186 ff INDEX 461 "Disease/' 113 flf {see also Strongy- losis) history of, 151 fF early records, 151 f former writers on, 152 distribution of (maps), 305 ff no district free from, 319 no periodicity of recurrence, 829 "years," 152, 305 ff summary of problems, 160 of conclusions, 161 relation to corn-feeding, 145 William Colquhouu's pamphlet, 146 John Colquhoun (" Moor and loch"), 139 " Klein's Disease," 153 ff, 330 not met with in Inquiry, 156, 161, 184 Cobbold's theory, 153 ff other views, 154 ff 328 Tom Speedy, 156 Committee's provisional view, 154 ff „ final view, 161 not due to tapeworms, 157 not due to Bacillus coli, 158, 217 ff, 221 not due to " preservation," 152, 403 not connected with geological forma- tion, 318 due to Strongyle worms in caeca, 201, 209, 220 pathology, 206 ff effects of on sexes, 179, 242 power of resistance to, 241, 326 always causes wasting, 157, 217 relation to weight, 157, 162, 217, 244, 327 undersized and late birds, 241 no autumn outbreaks, 180, 238 relation to wet moors, 368 relation to rainfall, 319 rapid recovery from, 442 ff sickly birds in autumn convalescent, 46, 180 Diseases, minor, of Grouse, 116 ff of skin, 150 Distribution of Grouse, 1, 3 Draining, 368 advantages of, 369 methods recommended, 369 by gamekeepers, 339 to discourage heather beetle, 379 Driving, see Grouse-driving Droppings, hard, 171, 326 soft, 171, 190, 325 " docker," 14, 172, 190 Drought, 299 ff favours Coccidiosis, 266, 299 unfavourable to Trichostrongylus , 225, 237 Dung-fly, 188 as carrier of coccidian spores, 258 not intermediate host of cestodes, 188 in Grouse droppings, 190 Duodenum, 166-7 habitat of small tapeworm, 167, 173, 199 effect of parasites on, 174 Eagle, 22, 410 Ectoparasites, 182, 184 relation to endoparasites, 184 Eggs, number of, 7 depends on healthiness of stock, 285 colour of, 8 intervals in laying, 7 size and colour, 8 f effect of weather on, 9 of snow, 9 f of frost, 10 ff • of wet, 9 f of disease on, 286 hatching of, 148 Egg stealing, 414 Egg changing, 445 Eimeria avium, see Coccidium avium Endoparasites, 192 relation to ectoparasites, 182 Euston, or " Stetchworth " system, 397 Feeding, hours of, 22, 81, 171 during incubation, 172 Feet, accidental injury to, 134 Fences, danger from wire, 23, 119 "bushing^' of, 23 Fencing of burnt areas from sheep, 355 Fighting, mortality from, 147 Filaria smithi, 202 Fires, accidental, 353 Flagellata, 207 Fleas on Grouse. See Geratophyllus Flies on Grouse, 188 Flight, powers of, 30 f Flooding, 17 f Food, 79 ff heather nearly all-important, 81 f but not indispensable, 81 various, 97 ff heather seed, 87 ff berries, 81 ff insects, 20, 90, 101-104, 194 corn, 29 462 INDEX Food — continued. percentages in summeij table, 82 winter, nature of, 88 greater quantity required in winter, 34, 81, 92, 94 percentages in winter, table, 89 proportion of animal and vegetable, 101 ff chemical constituents, 164 monthly dietary, 82-90, 96 f Food areas, overcrowding on, 90 Food plants, list and description of, 97- 101 Food supply heather-burning and, 349 relation of to migration, 95 Foreign species, introduction of, 69 Foster mothers, unsuccessful, 463 Fox, methods of destruction, 405 Fresh blood, introduction of, 32, 441 f unnecessary where birds migratory, 441 fl birds apt to wander, 443 risks of introducing, 445 Frost, effect of on eggs, 10 ff, 140 on pheasants' eggs, 11 on nematode larvse, 236, 325 interrupting breeding, 281 result of observations, 12 Gamedbalers' licences, 413 Gamekeepers, 387 f should be owner's servants, 388 relations with agricultural tenants, 390 terms of service, 390 should not be paid in " kind," 390 married and unmarried, 391 number required, 391 Head, 391 Under, Single, 393 ai-ea under one man's control, 391 f selection of, 392 essential qualifications, 392 personal qualities, 394, 402 f the " ideal," and the inefficient, 394 training of young, 394 importance of keenness in, 393 duties, 396 flP in ''off" season, 396 in nesting season, 396 f " Stetchworth " system, 397 improving nesting ground, 398 drains and springs, 399 grit supply, 399 vermin killing, 399 Gamekeepers — continued. butt building, 400 " bushing " fences, 400 bracken, destruction of, 400 estimating stock, 400 observing nests and broods, 396 f in shooting season, 400 ff Grouse driving, 395 cocks, killing down, 401 Autumn heather-burning, 401 in Winter, 401 vermin tracking in snow, 402 in Spring, heather-burning, 402 Game-laws Commission, 346 " Gapes " in Grouse, 201 Gastro-uterine gestation, 149 Geological formations in Scotland, 318 no relation to " Disease," 318 Gizzard, 81, 166-6 Goniodes tetraonisQaivA louse) on Grouse, 184 habits, 186 morphology, 185 eggs, 185 and skin disease, 150 Grazing rents and sheep rents, 347 f Gregarines in Grouse, 203 spores in alimentary canal, 203 Grit, 22, 107-112, 166 in Grouse chicks, 20, 108 size of, 107 f weight of, 108 quantity of, 107 geological constituents of, 108 quartz, always preferred, 108 f, 166 in partridge and pheasant, 107, 109 artificial introduction of, 110 during snowstorms, 112, 144 effect of grit-starvation, 110 control over loss of, 110 f berries as substitute for, 112 in blackgame. 111 functions of, 166 shot pellets as, 109 Grouse, history of name, 1 distribution, 1, 3 confined to Britain, 1, 3 acclimatisation, 1, 2 systematisation, 2-3 plumage, 3, 42 food, feeding habits, 22 pairing, 4 pugnacity, 5, 147 nesting habits, 6 if INDEX 463 Grouse — continued. eggs, 7 f care of brood, 16 dangers to chicks, 15 f habits of chicks, 15 migration, 16 wildnesSj 22 hardiness, 24 longevity, 41 minor diseases, 116 S resistance to disease, 243, 326 recuperative powers, 118 ff effect of weather on, 276 S numbers vary with rainfall, 320 methods of shooting, 422 ff netting, 412, 414 (See under separate headings) Grouse chicks, 15 ff dangers to, 15 disappearance of, 16 ff drowning, 17 f food, 20, 101 ff insect, 101-104, 194 f vegetable, 104 flight of, 21 liable to Coccidiosis, 248 ff ''Grouse Disease," see "Disease" Grouse driving, 26 f, 423 advantages of, 426 disadvantages, 426 effect on yield, 426 history of, 426 results in England, 426 f in Scotland^ 426 f rules for, 428 gamekeepers' duties, 396 management of, 395 heather-burning for, 357 minor days, 428 young and old killed by, table, 440 crossing of blood by, 425, 446 on Broomhead Moor, 446 f Grouse fly {Omithomyia lagopodis), 182, 188 morphology, 189 habits, 189 blood-sucking by, 182, 189 of ectoparasites, 187 Grouse in capacity, 450 ff coops, 450 food, 455 water, 451 grit, 455 mating experiments, 454 change of ground, 456 late nesting of, 457 Coccidiosis in, 454 Grouse shooting ; in foi-mer years, 347 to regulate stock, 422 ff methods of, 422 ff over dogs, 423 advantages, 423 disadvantages, 424 rules for, 424 young and old killed by (table), 440 driving, .9ee Grouse driving Gulls, as vermin, 410 EjElSOPROTBnS MANSONI, 202 Hand-rearing, 446 ff, 460 ff coops, 460 food, 465 water, 451 result of experiments, 464 Hatching, date of, 14 period of incubation, 14 early, value of, 434 late, result of, on stock, 435 on weight, 37 Hawks, not aU are vermin, 410 Heath, cross - leaved (Erica tetraliix), 90,99 Heather, bell {Erica cinerea), 99 Heather, common {Galluna vulgaris), 97 importance of as food, 81 f not indispensable, 81 old, as food, 83 f uselessness of, 84, 351 f various types, 82 ff winter, 82, 361 dwarf, 71, 83 short and long, 83, 361 young, most nutritious, 85 growth from seed, 85 „ from root, 85 seedlings eaten by sheep, 85 and by young Grouse, 85 not by adults, 86 blossom, 87, 97 seed, 87, 88 ff, 97 not eaten after January, 88 "frosted," 141,328 term defined, 142 good grain year, good year for, 87 effect on of weather, 275 ff burning, see Heather-burning raking, in time of snow, 143, 402 Heather beetle (Lochmcea suturalis), 370 as causing " frosted " heather, 371 former observations of, 371 distribution, 371 correspondence regarding, 373 f 464 INDEX Heather beetle — continued. types of heather attacked by, 378 f action on plant, 372 quantity to acreage, 373 records of damage by, 373-378 date of injury, 378 methods of search for, 372 analysis of heather samples, 373 life history, 382 incomplete, 386 influence of climate on, 378 „ of rainfall on, 378 moisture favourable to, 378 experiments with, 386 eaten by blackgame, 380 methods of destroying, 379 morphology, 383 f characters, 383 allied forms, 382 hibernation, 381 pairing, 386 Heather-burning, 20, 343 history of, 343 ff, 347 " keeper's delight," 345 beneficial to both Grouse and sheep, 346 f sheep-farmers' views, 346, 359 co-operation by shepherds, 359 in interests of landlord, 388 f „ of shooting tenant, 388 f to destroy " disease," 238 ff, 265 to discourage heather beetle, 356, 381 to provide food supply, 349 in interests of spoi't, 357 in strips, 353 ff „ large patches, 353 ff, 362 „ small patches, 347, 353 ff, 362 rules, 348 ff labour required, 349 areas, apportionment of, 349 ff rotation of, 351 estimating, 349 example of scheme, 363 choice of rotation, 361 methods of burning, 364, 360 back-firing, 355 second burning, 355 treatment of steep faces, 366 of flow ground, 366 of north slopes, 366 of knolls, 366 of peat hags, 367 of "grey '^heather, 356 of burns and streams, 357 of " white grass," 366 of " green ground," 366 statutory seasons for, 357 Heather-burning — continued. " Spring " and " Autumn," 358, 401- 402 not after nesting begun, 434 Autumn burning, 358 ff periods of re-growth after, 361 f objections to, answered, 364 Hedgehog, as vermin, 408 Helminthiasis, see Tapeworms, etc. Hens old, uselessness of, 437 f Heteralds papulosa, in Grouse, 202 common worm in poultry and pheasants, 202 Hymenolepis microps (Small Tape - worm), 199 habitat duodenum, 167, 173, 199 numbers present, 199 difficult to detect, 199 associated with bacterial infection, 200, 219 seasonal prevalence, 199 intermediate host not discovered, 193, 200 Immigration of fresh stock, 441 f Incubation, effect of on weight, 36 period of, 14 Insects, as food, 101-104 parasitic, 184 ff as carriers of coccidian spores, 204 Intestine, small, 168 upper and lower portions, 168 habitat of large tapeworm (Davainea), 168 convolutions in, 169 Isolated moors, 444 loeodes ricinus (Dog-tick), on Grouse, 191 as nymphs and larvae, 191 causing acute skin disease, ISO Jackdaws, as vermin, 409 beneficial effect of reducing, 409 "Jugging," 24 Kestrel, beneficial, 410 Kidneys, 177 " Klein's Disease," see " Disease " Late shoots, 421 Leg-feathering, 44, 60, 62, 53 Leucocytoeoon lovati, 204 life history, 204 Lice on Gi-ouse, see Goniodes, Nirmus Liver, 167, 176 functions of, 169 post-mortem changes in, 176 INDEX 465 Liver — continued. effect of Coccidiosis on, 258 not affected by Strongylosis, 176, 213 Bacillus coli in, 220 Lochmcea suturalis, see Heather beetle Longevity of Grouse, 41 Lungs, 175 post-mortem appearance, 175 KALLOPHAGA (Bird-lice), on Grouse, 184 Maps, showing incidence of disease, 304 ff deductions from, 319 Mating, experiments in, 454 Meteorological districts, 276 Migration, 28 ff seasonal, 5 wholesale, 30 relation to food supply, 95 affecting stock regulation, 32, 95, 441 f not universal, 441 f as affecting crossing of blood, 442 as re-stocking vacant ground, 442 f Mites (Aleurobius farina:) on Grouse, 190 Monocercomonas, 205 Monocystis (sp), 203 spores in alimentary canal of Grouse, 203 Moor management, 321 f defined, 327 examples of, 333 ff deductions from, 341 Mortality in April and May, 210 seasonal, in cock and hen, 236 ff, 326 ff causes of, 113 ff accidental, 119 ff in blacli^ame, 121 f from fighting, 147 Moult, 37 normal, 37 deferred, 44, 148, 179 of cock and hen different, 36 f, 148 effect of disease on, 46 effect of, on weight, 36 f risks attending, 148 Nematodes, non-parasitic, 221, 324 Nesting, 6 ff sites, 6 date of, 6 early, advantageous, 434 second, 435 Nesting — continued. strain of, 435 " Nesting-patch " on hen, 59, 68 letting Grouse, 412, 414 Mirmus cameratus (Biting louse), on Grouse, 186 habits, 187 morphology, 187 eggs, 187 Observation area, 450 (Esophagus, 165 Old and young birds, 439 f proportions in "dogging" and "driving" (table) 440 Old birds undesirable, 437 f Ornithomyia lagopodis, see Grouse-fly Ovaries, 75 effect of " disease " on, 177 Over-crowding on food areas, 90 Over-sitting, 243 Over-stocking, relation to disease, 420 Oviduct, 178 Packing, 4, 26 reasons for, 27 f in relation to age and sex, 26 Pairing, 4 effect of weather on, 4 effect of snow on, 4 sometimes postponed, 13 of barren birds, 177 Pancreas, 167 Parasites, 182, 241 Partridges methods of stock management, 421 f Peregrine falcon, 22, 408 Pharynx, 165 Physiology, 160 ff Pigmentation, physiology of, 61 of feathers, 51 " Piners," how produced, 436 in autumn, 437 description of, 437 Plumage, 3, 42 ff local variations of, 69 f in cocks, classification of types, 71 in hens, classification of types, 72 uniformity the general rule, 47, 56, 70 seasonal changes, 42 ff in cock, 48-54, 66-67 "Winter" and "Summer," 42 f,47 " Spring " and " Autumn," 45, 47 2 G 466 INDEX Plumage — continued. Ogilvie-Graut's theory, 43 f, 55 Millais's theoryj 45 in hen, 64-65, 67-68 re-pigmentation, 51 as guide to sex, 74, 76 as guide to age, 77 Pneumonia, 175 never observed, 161 Poached game, facilities for sale of, 413 Poachers, 411 fF professional, 411 occasional, 413 prevention of, 411 f in former days, 412 snaring ou stocks, 412, "becking," 412 netting, 412, 414 egg-stealing, 414 Poisoning, 136 septic, in Grouse, 137 Polecat, 408 " Preservation - theory " of "Grouse Disease," 152, 403 Primary feathers, 77 Protoaoa, 202 Proventriculus, 165 Ptarmigan, moults of, 52 Rainfall, effect on heather beetle, 378 relation to yield of Grouse, 139, 319 fF Raven, as vermin, 410 Rectum, 168, 172, 175 inflammation of, 175 Re-pigmentation of plumage, 51 Rook, as vermin, 409 Rotation, in heather-burning, 361 SCATOFBAGA STEROORARIA, see DuUg-fly Scent, loss of while sitting, 14 Sex, methods of ascertaining, 177 f in relation to plumage, 42 flf „ to weight, 33 fF „ to packing, 27 Sheep, destructive to seedling heather, 355 fencing burnt areas from, 355 Sheep-drains, 17, 135 Shot, wounds from, 128 ff, 131 alleged poisoning by, 136 Skin disease, 160 Snaring on corn stocks, 412 Snow, effect on pairing, 4 on nesting, 6 on health of stock, 25, 143, 331 on migration, 6, 143 Snow — continued. "jugging" in, 25 breaking of surface, 143, 402 vermin tracking in, 402 " Soft-shell," 149 Spirochceta lagopodis, 203 SpirochcEtOf lovati, 203 Spirochmtacea, 203 Sporozoa (blood parasites) of Grouse, 203 Spleen, 150, 176 " Stetchworth " or " Euston " system, 397 Strongylosis, 204 ff the "^ Grouse Disease" of adults, 201, 209 in normal birds, 214 almost universal in Grouse, 208, 323 f Cobbold's discovery of, 153 ff a progressive ailment, 214 a spring disease, 180, 238, 265 due to Strongyli, 201, 209, 220, 323 occurs in cseca, 173, 175, 201, 208 pathology, 206 ff effect on ceeca, 212 f, 221 post-mortem appearance, 212 S effect on moult, 46 on reproductive organs, 179, 283 no effect on liver, 213 affecting weight, 157, 217 affecting temperature, 217 seasonal mortality from, 49, 211, 238 ff, 326 recovery from, 216, 240 toxcemia in, 219 f helminthic toxins in, 221 relation to Bacillus coli in tissues, 158, 217 f infection, artificial, 233 ff „ natural, 236 remedial measures, 235 Strongylus pergracilis, see Tricho- strongylus pergracilis Stoat, methods of destruction, 406 Stock management, 416 meaning of term, 416 statistics, 416 f generalisations, 417 examples of typical moors (table), 418 f The " ideal," stock, 415 in relation to acreage, 416 "Winter" and "Summer," 416 dependent on winter food supply, 416 large " Winter," undesirable, 430 ascertainment of, 400 f, 422 regulation by shooting, 401, 420 on let moors, 421 INDEX 467 Stock management — continued. in good season, 424 in bad season, 424, 431 methods, 422 healthiness to be considered, 433 and results of nesting, 422 migration as affecting, 442 f necessity for co-operation, 432 rules for, 432 objects to be aimed at, 432 sickly birds in autumn may be spared, 433 f " cheepers " should be killed out, 434 old birds undesirable, 437 f ratio of young and old, 439 artificial improvement, 441 by fresh blood, 441 f migration and re-stocking, 441 f where Grouse non-migratory, 444 egg-shifting, 445 importing birds and eggs, 441, 445 hand-reared birds, 446 summary of conclusions, 44(5 Stomach, 166 n Syngamus trachealis ("Gapes-worm"), in Grouse, 199 TAENIA CALVA, see Davainea urogalli Teenia cesticillus, see Davainea cesticillus Tcenia microps, see HymenoUpis microps Tapeworm, see Cestoda Tapeworm, large, see Davainea urogalli small, see Hymenolepis microps Temperature (body), of Grouse, 216 Tentsmuir, 106, 316 Testes, 76, 177 effect of disease on, 177 Threadworm, see Trichostrongylus and Trichosoma Ticks, on Grouse, 191 (see Ixodes) Toxcemia, 219 f Toxins, helminthic, 221 Trichomonas eberthi, 205 in caecal contents, 206 Trichosoma longicolle, 201 less common than Trichostrongylus, 174, 201 habitat duodenum, 167, 173, 202 structure, 202 pathological effect small, 174, 202 but allied to dangerous parasite in man, 201 Trichostrongylus pergracilis, 200 f, 206 cause of " Grouse disease " in adults, 201, 209, 220 habitat cseca, 173, 176, 201, 208 Trichostrongylus pergracilis — continued. numbers present, 208, 323 methods of counting, 208 almost always present, 208 characters, 206 life history, 221 ff, 324 development, 222 within host (morula), 222 outside host, 223 artificial cultivation, 223 ovum, development of, 224 moisture necessary to, 107, 223, 237 effect of drought on, 223, 236 f embryo, structure of, 226 first ecdysis, 227 quiescence during cold weather, 239 metamorphosis, 227 larvse, 228 encystment, 230 migrations, 231 on heather, 107 synopsis of, 232 larvae, experimental administra- tion of, 233 effect of frost on, 236, 326 „ of drought on, 236, 325 „ of sea spray on, 326 maturity and reproduction, 224, 234 methods of destruction, 237 Trypanosoma eberthi, see Trichomonas eberthi Undersized birds, 241, 437 Vermin, 18, 403 ff list of, 406 ff keepers' duties, 402 " balance of Nature," 403 sometimes beneficial, 405 vermin-killing and "disease," 403, 404 tracking in snow, 402 methods of destruction, 405 ff golden eagle, 22, 410 fox, 406 stoat, 406 weasel, 408 polecat, 408 hedgehog, 408 cat, wild, 408 cat, domestic, 408 peregrine, falcon, 408 crow, 408 f rook, 409 468 INDEX Vermin — continued. jackdaw, 409 raven, 410 hawks, 410 gulls, 410 Water-drinking by Grouse, discussed, 20 f, 104-107 by adults, 105 f, 133 by chicks, 20, 105, 138, 261 in hand-reared birds, 21, 105, 461 in sickness, 265 artificial supply, 339, 398 Weasel, as vermin, 408 Weather, 9 ff, 273 ff effect of, on eggs, 13 on nesting, 9 on breeding, 13, 283 on chicks, 16 on health of stock, 24, 276 ff on heather, 276 ff Analysis of, during years of Inquiry, 273 ff Weight of Grouse, 32 Weight of Grouse — continued. as testof disease, 167, 162, 217,240,326 as sign of health, 33 seasonal changes in, 33 ff, 38, 40 effect of courtehip on, 33 if, 38 of moult on, 36 f of late hatching on, 37 of incubation on, 36, 38 relation to disease, 167, 162, 217 effect of Coccidiosis on, 256 of Strongylosis on, 157, 217 of Helminthiasis on, 219 in relation to sex, 33 ff local variations in, table, 39 records, 40 " White diarrhoea," 269 Willow Grouse, 69 crop contents, 144 Wing feathers as guide to age, 77 Wire collision with, 119 ff Woods as shelter, 25 Young and old birds, proportions of, table, 440 Finis PRINTED AT THE EDINBURGH PRESS, g AND II YOUNG STREET, EDINBURGH. SOME NOTICES OF THE FIRST EDITION OF THE GROUSE IN HEALTH AND IN DISEASE Published August 1911 The Times, August loth, 1911. The primary object of the Committee was to investigate the so-called "Grouse Disease," and they have evidently felt it their duty to take the widest possible view of the problem before them. With the sometimes questioned exception of the St Kilda's wren, a bird of no economic importance, the Grouse is the only bird "peculiar" to Great Britain and Ireland. The present monograph gives the fullest possible account of the bird, both in health and in disease. In fact, apart from man and maybe the frog, it is doubtful if any vertebrate has been so thoroughly investigated. Its life-history, its habits, its home life, its anatomy, its physiology, even its psychology, its weaknesses, its ailments are in these volumes remorselessly revealed. The book is most beautifully illustrated and owes much to the artistic brush of Dr E. A. Wilson, the Field Observer, and the whole appearance of the work is a credit to the publishers. It is also an example of what a few energetic men can produce when unhampered by oflScial restrictions and red tape. The present report is the antithesis of the ordinary Blue Book, yet it has been produced at an amazingly small cost. During the whole of the inquiry the average income expended on the work was but £727 a year, and the whole of the inquiry has not cost more than £4,366, every penny of which has come out of private purses. That this has been done is due in the main to the energy and self-sacrificing devotion to the work of the inquiry shown by the chairman. Lord Lovat, and the secretary, Mr A. S. Leslie. The Morning Post, August loth, 191 1. The "Grouse Disease" Inquiry, which had been undertaken some six or seven years ago by a Departmental Committee of the Board of Agriculture and Fisheries, has issued its report in two volumes, entitled " The Grouse in Health and in Disease." These volumes have been dedicated by gracious permission to the King. The two volumes are lavishly illustrated and beautifully printed, and they reflect great credit on the Field Observer, Dr E. A. Wilson, on the secretary, 469 470 PRESS OPINIONS Mr A. S. Leslie, and, above all, to the chairmai). Lord Lovat, whose knowledge and experience and unbounded energy have succeeded in setting a new standard in the books dealing with the health and disease of game birds. The Field, August loth, 1911. The final report of the " Grouse Disease " Inquiry Committee, which has just been issued, is most interesting, and by far the most complete account of the life-history of the Grouse in health and disease that has yet been published. It is issued in two volumes. The report is full of valuable information both to the sportsman and to the scientist ; it is handsomely bound, well illustrated, and will be a welcome addition to all libraries, whether sporting or otherwise. The Scotsman, August loth, 1911. Taking the two volumes together they form a most remarkable contribution to our knowledge of the natural history of the Grouse, a contribution which is the more remarkable in view of the fact that the whole of the funds available for the purpose have not exceeded £4t,36Q. While at this season of the year there is a temptation to linger over the more practical portions of the report, to do so unduly would give a false impression of the scope and aim of the material which has been gathered together in it, and which makes it perhaps the completest monograph on any bird that has ever been published. Complete as it is, it has opened up many lines of inquiry, many of them of distinct practical importance which still await investigation. The Glasgow Herald, August loih, 1911. That the inquiry has been thorough in every sense of the term must be apparent to any one who takes up any one chapter — we say any one advisedly — of the twenty-three that make up vol. i., not to mention the maps and the appendices that are reserved for vol. ii., with the fifty-nine full-page plates, mostly in colour, and the copious illustrations in the text. If any further indication of the thoroughness with which the work of inquiry has been carried through should be necessary, we have it in the roll-call of the specialists who have formed the scientific staff, of whom there were fourteen, every one of them eminent in his particular sphere. The Dundee Advertiser, August loth, 1911. At last the mystery of " Grouse Disease " is solved, and the whole details of the great work which has been carried out by the Committee of Investigation can be found in the two fine volumes published to-day under the title, " The Grouse in Health and in Disease." The book forms a complete monograph on the Red Grouse — no fuller and finer work has ever been bestowed on an individual bird. To the vast class of sportsmen, with no strong scientific bent, the chapters on practical management of Grouse moors by Lord Lovat will appeal most PRESS OPINIONS 471 strongly. Never before lias the subject been treated in the same exhaustive way, and there can be no doubt whatever that the Grouse has found in Lord Lovat its champion, and from his very apparent love of his subject he will be perfectly satisfied to find his reward in popularising modern and sensible treatment of Grouse ground. The Spectator, August 12th, 1911. The Committee of Inquiry on " Grouse Disease," appropriately enough with the opening of the shooting season, have issued their final report, and they are to be congratulated, not only upon the success to which their labours have led them, but on the admirable form in which they present their conclusions to the public. The Committee have succeeded in their object. They have discovered the origin and the meaning of what has come to be generally known as " Grouse Disease," and incidentally they have made clear a number of points on which there existed doubt and confusion. Country Life, August 12th, 191 1. The final report of the Committee of Inquiry on " Grouse Disease," forms a vastly interesting and exhaustive monograph on the life-history of the Red Grouse both in health and disease, and is undoubtedly one of the most complete and valuable works that have ever been placed before the public. The Pelican, August 2yfd, 1911. If all official Blue Books were as interesting, as ably compiled, and as excellently illustrated as Lord Lovat's Grouse Commission Report there would be a greater demand for those particular volumes than at present exists. The Illustrated London News, September gth, 191 1. It is a source of gratification alike to scientists and to sportsmen that the " Report of the Committee of Inquiry on ' Grouse Disease ' " is now at hand in the shape of two large handsome volumes, thoroughly illustrated, and printed in artistic style. The real title of the work is " The Grouse in Health and in Disease," so that apart from the main feature of the volumes dealing with the tjrpical bird-ailment, we find in this work a very complete monograph of all that concerns the bird and its welfare. The Irish Field, September 16th, 1911. After very lengthy deliberation the report of the Commission on " Grouse Disease" has appeared in the shape of two weighty volumes, and the delay is to be forgiven in the face of the supreme interest of the work. The Lancet, September 30th, 1911. The report is a model of what such work should be, and is a good example of the way in which scientific medicine is now bound up with every phase of social life. 472 PRESS OPINIONS Nature, October 26th, 191 1. Although^ as its name implies, -the " Grouse Disease " Inquiry Committee was formed to investigate the nature and causes of the mortality which has been so prevaletit of late years in the one species of game bird peculiar to the British Isles, it has accomplished a great deal more than this. For in the handsome volumes before us we have the life-history and organisation of the Grouse, coupled with those of the various parasites by which it is infested, described in a manner never before attempted in the case of any other wild bird. This magnificent piece of work, it should be added, has been carried out from start to finish by private effort and enterprise ; for although the Committee was officially appointed by the Board of Agriculture and Fisheries in the spring of 1906, its funds have been entirely furnished by private subscriptions. The whole investigation is, indeed, a striking, and we believe, a unique example of what can be done by the combined efforts of sportsmen, gamekeepers, field-observers, and biological experts ; and to Lord Lovat, the chairman, and all those who have worked with him are due the gratitude of naturalists and sportsmen, not only in the British Islands, but throughout the world. a o —I CO 5i LU LU CO C3 >- Or -^~ ^^ O ^ ^ v_ "^ oo