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The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgementTown of the source. The thesis is to be used for private study or non- commercial research purposes only. Cape Published by the University ofof Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University ENVIRONMENTAL INFLUENCES ON MOULT AND MOVEMENT STRATEGIES IN SOUTHERN AFRICAN WATERFOWL by Town Mduduzi Ndlovu Cape of Thesis submitted in fulfilment for the degree of Doctor of Philosophy in the Percy FitzPatrickUniversity Institute, Department of Zoology, University of Cape Town, South Africa Supervisor: Prof Graeme S. Cumming Co-supervisor: Prof Phil A.R. Hockey December 2012 DECLARATION This thesis reports original research conducted under the auspices of the Percy FitzPatrick Institute, University of Cape Town. All assistance received has been fully acknowledged. This work has not been submitted in any form for a degree at another university. …………………. Mduduzi Ndlovu Town Cape of Copyright © 2012University Mduduzi Ndlovu Recommended citation: Ndlovu, M. 2012. Environmental influences on moult and movement strategies in southern African waterfowl. PhD thesis, Percy FitzPatrick Institute, Zoology Department, University of Cape Town. 1 To Sibusisiwe Ndlovu my mother and my daughter (named after her) Town Cape of University 2 TABLE OF CONTENTS ACKNOWLEDGEMENTS ...................................................................................................... 5 GENERAL ABSTRACT .......................................................................................................... 6 CHAPTER 1 General Introduction ............................................................................................................ 8 CHAPTER 2 Phenotypic flexibility of a southern African duck during moult: do northern hemisphere paradigms apply?................................................................................................................ 21 Town CHAPTER 3 Body mass and pectoral muscle size fluctuations in African ducks during moult ............ 44 Cape CHAPTER 4 Interactions of environmental conditionsof and the timing of breeding and moult in waterfowl ........................................................................................................................... 64 CHAPTER 5 Moult-site fidelity of Egyptian Geese in South Africa ..................................................... 85 CHAPTER 6 University Life history and location dominate the daily movement patterns of Egyptian Geese in South Africa .................................................................................................................... 109 CHAPTER 7 Synthesis .......................................................................................................................... 134 3 APPENDIX ............................................................................................................................ 146 Phenotypic flexibility of a southern African duck during moult: do northern hemisphere paradigms apply?.............................................................................................................. 147 Satellite telemetry of Afrotropical ducks: methodology details and assessment of success rates ................................................................................................................................. 154 Responses of an African wading bird community to resource pulse are related to foraging guild and food-web position ............................................................................................ 164 Towards a unification of movement ecology and biogeography: conceptual framework and a case study on Afrotropical ducks ........................................................................... 172 Town Linking avian communities and avian influenza ecology in southern Africa using epidemiological functional groups .................................................................................. 183 Cape Host association, biogeography and phylogenetics of avian malaria in southern African waterfowl .........................................................................................................................of 194 The ecology of Influenza A viruses in Wild birds in southern Africa ............................ 204 Understanding the ecology drivers of avian influenza virus infection in wildfowl: a continental-scale Universitystudy across Africa .............................................................................. 213 4 ACKNOWLEDGEMENTS I thank first and foremost my supervisors Prof Graeme Cumming and Prof Phil Hockey with whom all of this work was done. Without their guidance and patience, none of this would have been possible. Secondly I thank Dr Leo Bruinzeel, Gregory Mutumi, David Nkosi, Hassan Babiker, Dominic Henry, Sharon Okanga and many other volunteers for their help with field work. Leo Bruinzeel also made useful suggestions for Chapters 2 and 3. Margaret Koopman and Dr Rob Little proof-read my thesis and made helpful comments and suggestions. Thank you very much. The following people read some parts of the thesis and gave useful suggestions: Gregory Mutumi, Dr Rowan Martin and Dr Susan Cunningham. Dr Tim Reid assisted me with GAMM statistics for Chapter 6. Town I‟m grateful to the Percy FitzPatrick Institute staff, particularly Hilary Buchanan, Tania Jansen, Chris Tobler, Dr Rob Little, Anthea Links and Lionel Mansfield for all the logistical support rendered me during this study. Cape I would like to thank Joel Avni, Sampie van der Merwe and Barberspan Bird Sanctuary staff (particularly Amos Koloti, Sydwell Setuki,of Mmapula Kakgodi and Andrew Mvundle) for supporting this project at Barberspan. For assistance in working at Strandfontein I‟m grateful to Morné Carstens, Eben Olderwagen, Dalton Gibbs and the Strandfontein Wastewater Treatment works management staff. Permits for this research were issued by Cape Nature and the Northwest Parks Board. The project was funded through a USAID grant awarded to GSC under the Wildlife Conservation Society‟s Global AvianUniversity Influenza Network for Surveillance (GAINS) program. Further funding came from the DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, KW Johnstone Doctoral Package Scholarship and the NRF Africa Scholarship. Finally I would like to expresses my sincere appreciation to Noni and the rest of my family whose understanding, encouragement, patience and moral support was critical throughout. 5 GENERAL ABSTRACT Waterfowl annual life history events in north-temperate regions are driven primarily by predictable seasonal variations in temperature. In contrast, the spatio-temporal availability of adequate resources to waterfowl in the semi-arid regions of southern Africa is determined by rainfall which is extremely variable in timing and intensity. I studied the environmental influences on flight-feather moult and movement strategies of southern African waterfowl. Six duck species that are fairly common in most parts of South Africa were selected for the study, namely; Egyptian Geese Alopochen aegyptiaca, Spur-winged Geese Plectropterus gambensis, South African Shelducks Tadorna cana, Yellow-billed Ducks Anas undulata, Red-billed Teals A. erythrorhyncha and Southern Pochards NettaTown erythrophthalma. I chose two study sites to represent the extremes of environmental conditions in southern African, namely Barberspan (summer-rainfall region) and Strandfontein (temperate winter-rainfall Cape region). I investigated the underlying responses of Afrotropical waterfowl to stochastic varying environmental conditions in southernof Africa and the life-history strategies they have evolved to cope with this variability. The study also compares and contrasts the life-history strategies of southern hemisphere waterfowl with those of the northern hemisphere. Egyptian Geese undergo substantial phenotypic changes during moult, including asynchronous changesUniversity and these appear to have evolved to allow moult to be completed as rapidly as possible in a stochastic environment. Spur-winged Geese, South African Shelducks, Yellow-billed Ducks, Red-billed Teals and Southern Pochards also exhibit strategic fluctuations in body mass and pectoral muscle size that are geared towards reducing wing-loading, enabling birds to fly before moult is completed. Waterfowl in southern Africa (with the exception of South Africa Shelduck), south-west Australia, Europe and North America time their breeding period to coincide with peaks in the 6 availability of both food and breeding sites. Northern hemisphere species moult when temperatures are warm and before food and aquatic habitats approach their winter minima. By contrast, southern-hemisphere waterfowl delay the onset of moult until the dry season, when food and aquatic habitats are few, opting to moult when both food and aquatic moulting habitats are few. Egyptian Geese movement patterns were found to be significantly influenced by their geographic location within southern Africa. Telemetry and colour-rings indicated moderately high moult-site fidelity, despite the anthropogenic modification of South Africa‟s landscape, particularly the increased number of permanent artificial water bodies which would be expected to lower moult-site fidelity. Moulting birds displayed crepuscular patterns of activity and nocturnal retreats to safety. Barberspan birds undertakeTown