An Introduction to the Behaviour of The
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AN INTRODUCTION TO THE BEHAVIOUR OF THE GOLDENEYES : BUCEPHALA ISLANDICA AND B.CLANGULA (CLASS AVES, FAMILY ANATIDAE) by MILES TIMOTHY MYRES B.A., University of Cambridge, 1953 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ARTS in the Department of Zoology We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA April, 1957 i ABSTRACT In the summers of 1955 and 1956 a field study was undertaken on the behaviour (locomotory, comfort, agonistic, courting, coition and brood) of the Barrow's Goldeneye (Bucephala islandica) in the Cariboo District of British Columbia. This is the first stage of a five year study of the behaviour of Sea Ducks of the Tribe Mergini. An attempt has been made to summarise the behaviour of B.islandica and also of the closely-related species B.clangula, that is described in the literature. Generic similarities, and specific differences, in the courtship displays of these two species have been described. An attempt has been made to discover the likely sources of these displays from among the locomotory, comfort ar agonistic behaviour patterns. Illustrations of the postures and movements described in the text have been made from films by the author, and two other sources. An attempt has been made to link items of behaviour to the ecological, biological and systematic aspects of duck biology. Thus both the behaviour itself comes to have a biological setting and raison d'etre, and behavioural aspects of breeding and population biology, and population management and manipulation,may be better understood. Among Comfort Movements Drinking appears to have given rise to a courtship display found chiefly in the pre-coition sequence. Wing- and Leg- Stretching is also a comfort movement found in display (only in the pre- coition behaviour). Preening generally (especially Splash-Bathing) occurs frequently under conditions of stress e.g. after a territorial encounter and after coition. The Upwards-Stretch, Wing-Flap, Tail Wag complex of ii movements is also frequent under conditions of stress, and occurs especially as a "signing-off" (? appeasement) display at the end of an encounter. Agonistic behaviour is interesting, in that the diving ducks tend (goldeneye particularly) to use underwater diving as their major aggressive tactic. Threat may derive from intention diving. The "alarmed" position is hard to derive from other postures. Inter-specific aggression is fre• quent and indicates that the Aythyini are more of an irritant to goldeneye than are the Anatini. Case-histories of inter-specific aggression helped to throw light on the nature of territory in goldeneye, and on fatigue and refractory periods in the attack motivation. Goldeneye have a wide variety of courtship displays. The Head-Up and Head-Raised positions (with the Neck-Withdrawing movement) are rather alike in the two species. The Head-Throw of B.clangula is much more ex- traae in form than the equivalent movement in B.islandica. In B.islandica the Pseudo-Kick and Kick are much less differentiated, than the Head- Throw and Head-Throw-Kick of B. clan aula. An analysis is made of the two forms of pumping motions, to show their basic similarity, but species differentiation. The Coition Sequence is very similar in the two species. There is a marked Post-Coition display. The downies leave the nest by scrambling up the inside of the nest cavity, and tumbling from the nest-hole all together. The female has a special call which is used to force all the downies off at one time. On the lake the same call gathers; the young together around the female. The iii importance of this means of ensuring that the young fledge together is discussed. The actions of the female at fledging are described. Females are poor guardians of broods, but they show considerable hostility towards each other during the brood period. Downies greet each other and the female by a movement which at first resembles the Rotary Pumping of the adult drake, and the female. Rotary Pumping thus is a "greeting" movement. RESERVATIONS ON USE In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I stipulate, however, that owing to the fact that some of the raw data of this thesis was loaned to me by other students of goldeneye behaviour for use in this thesis only, restrictions must be placed on its use hereafter. Publication of the text is reserved to the author. Use of figures, or quotation, from the text^is only permitted if both I, and the other parties concerned, have given leave in writing. Mr. Charles Walcott and Mr. Benjamin Dane may be reached through the Dept. of Zoology, Cornell University, Ithaca, New York, U.S.A. Dr. Frank McKinney may be located at the Delta Waterfowl Research Station, Delta, Manitoba, Canada. The author may be reached through the Dept. of Zoology at the University of British Columbia, Vancouver, Canada. The Librarian in making this thesis available for study shall obtain written assurance from the loanee that these conditions are understood, and that the loanee will abide by them. Copying or publication of this thesis for financial gain will, likewise,not be allowed, without the written permission of the persons mentioned above. Department of Zoology The University of British Columbia, Vancouver 8, Canada April, 1957. ix AC KNOIvLEDGEffi NTS Dr. I. McT. Cowan, Head of the Department of Zoology, University of B. C, invited me to Canada and suggested subjects for study. I am grate• ful for all that he has done to encourage and facilitate this work. With• out his interest and enthusiasm it would never have been a success. I am indebted to my mother, Mrs. J.M.L.Myres, for financial aid that enabled me to travel to British Columbia, and to live through the first year. During the years 1955-57, I was supported by a Wildlife Conservation Fellowship under the auspices of Canadian Industries Limited. I was also an Overseas Travelling Scholar of the Worshipful Company of Goldsmiths' of London. To the interest in pure learning, and in education, exhibited by these bodies I am especially grateful. In the summers of 1955 and 1956 equipment and supplies were made available under a Grant for Research from the National Research Council of Canada. I am glad to acknowledge the loan of a movie-camera in 1955 from Mr. R.J.Pop, of Vancouver. This thesis would be considerably the poorer, were it not for the pictorial material, the greater proportion of which has been made avail• able to me by other ethologists. I am especially grateful to Mr. Charles Walcott and Mr. Benjamin Dane, formerly of Harvard College, for allowing me to work over their film, while their own paper was yet unpublished. This was an immense privilege. I cannot express my gratitude strongly enough. Dr. Frank McKinney of the Delta Waterfowl Research Station, Mani• toba, also lent me some film, and has been a constant source of moral support. X Mr. Theed Pearse of Comox, B.C., kindly allowed me to look through his diaries for information on goldeneye displays. Mr. G. F. van Tets and Miss Mary F. Jackson made available translations of foreign papers. Messrs. George Tucker, Clark Tucker and Ward Herrick of Williams Lake, B. C., allowed me to camp on their property, and were kind at all times. Mrs. Nancy MacAllister often helped me in the field. I am grateful to my friends Mary F. Jackson, Dr. B. Baggerman, and R.B.Weeden for reading parts of the manuscript (often more than once). Mary Jackson was a constant source of reference for biological facts about Barrow's Goldeneye. Dr. Baggerman helped me erradicate some of the worst errors in regard to ethological theory. Dr. M.D.F.Udvardy supervised the study, and was a continual source of ideas. I am grateful to Dr. W.Drury of Harvard for putting me in contact with Charles Walcott and Benjamin Dane. iv . TABLE OF CONTENTS INTRODUCTION 1 Ethological Studies and Phylogenetic Relationships 2 The Derivation of Sexual Displays 5 Current Studies and the Literature 11 The Pacific Coast 13 Equipment 14 Organisation 16 THE GOLDENEYES (BUCEPHALA ISLANDICA and B.CLANGULA) 17 THE DISTRIBUTION AND ANNUAL CYCLE OF BARROW'S GOLDENEYE 18 Geographical Distribution 18 Moult Migration as an Outbreeding Mechanism within the species 19 Matrilocality (with Coastal Pairing) as an Isolating Mechanism within the species 20 Hybrids 21 Winter Distribution and Winter Behaviour 24 Spring Migration 27 Territory (Mating and Brood) and Nesting 28 Deficiences in Brood Guardianship 30 Age at first breeding 31 Post-breeding Dispersal 31 Summary 32 NON-SOCIAL BEHAVIOUR 34 Locomotory Movements 35 Flight 35 Diving 39 Swimming 42 Walking 44 Comfort Movements 47 Feeding 49 Drinking 51 Tail-Wag 52 Head-Shake Complex 53 Water-Dip Complex 55 Upwards-Stretch 56 Wing-Flap 57 Wing- and Leg-Stretch 58 Yawning 59 Ear-Scratch 59 V Forward-Preening 60 Sideways-Preening 60 Back-Preening and.HeadrEolliBg 60 Splash-Bathing 6l Thigflotaxis 62 SOCIAL BEHAVIOUR , • 73 Agonistic Behaviour 74 Intra-specific Agonistic Behaviour between males -74 Crouched Posture • 79 Laying Neck on Water (Threat Posture) 81 The Attack 84 Surreptitious Encroachment 39 Expectancy Look ("Alarmed" position) 91 Inter-specific Aggressive Behaviour (inc. Table I) 96 Courting Displays 108 General Account •• 108 Female 117 Jiving 120 Deep Jiving 124 Male 128 Head-Up Neck-Withdrawn 128 Head-Raised Neck-Withdrawn 132 Pseudo-Kick and Kick 141 Head-Throw 148 Head-Throw-Kick 158 Rotary Pumping 179 Bowsprit Pumping and Bowsprit Position 187 Masthead • -201 Backwards Swimming Display 204 The Coition Sequence 209 General Account • .• -209 Invitation to Coitus • 211 vi Water-Flip 212 Wing- and Leg-Stretch *..