Integrated Analysis of the Movement and Ecology of Wild Dingoes in The
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Integrated analysis of the movement and ecology of wild dingoes in the arid zone Jack Tatler A thesis submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy April 2019 School of Biological Sciences The University of Adelaide, South Australia Table of Contents Abstract ...................................................................................................................................................... i Thesis Declaration .................................................................................................................................... iii Acknowledgements .................................................................................................................................. iv Chapter 1. Introduction ............................................................................................................................. 1 Chapter 2. Phenotypic variation in coat colour and mating strategy in a wild population of pure dingoes Canis dingo................................................................................................................................... 9 Chapter 3. Resource pulses affect prey selection and reduce dietary diversity of dingoes in arid Australia .................................................................................................................................................. 32 Chapter 4. High accuracy at low frequency: detailed behavioural classification from accelerometer data ......................................................................................................................................................... 56 Chapter 5. Extreme individual variation in resource selection of an apex predator .............................. 82 Chapter 6. Accelerometer informed time-energy budgets reveal the importance of temperature to the activity of a wild, arid zone canid .......................................................................................................... 109 Chapter 7. Final Discussion ................................................................................................................... 130 References ............................................................................................................................................. 134 APPENDIX 1. Supplementary material to Chapter 2 ............................................................................. 165 APPENDIX 2. Supplementary material to Chapter 3 ............................................................................. 170 APPENDIX 3. Supplementary material to Chapter 4 ............................................................................. 190 APPENDIX 4. Supplementary material to Chapter 5 ............................................................................. 200 APPENDIX 5. Supplementary material to Chapter 6 ............................................................................. 204 Abstract The behaviour and use of space by mammalian predators influences the structure and function of ecosystems. Mammalian predators are often highly mobile, and in resource limited environments they need to move through spatially distinct habitats in search of prey, water, refuge, and conspecifics. This increases connectivity between ecosystems and can have important ecological implications for food web stability. Underlying a predator’s decision to move is the need to balance requirements for energy acquisition and expenditure. Advances in remote monitoring technology are increasing our ability to gain detailed, quantitative insights into the movement ecology and ecophysiology of wild animals. However, methodological and analytical complexities have impeded the integration of different biologging tools. In this thesis I explored the biology of Australia’s largest terrestrial predator, the dingo Canis dingo, and adopted an integrative approach to studying the ecology of wild individuals. My research focused on the genetics, behaviour, resource selection, and energetics of a population of dingoes in remote central Australia. The population exhibited high genetic purity (mean purity > 90%) and clear phenotypic variation in coat colour. Genetic analysis of 83 individuals revealed high levels of relatedness, and both promiscuous and monogamous mating strategies. Morphological analysis of prey remains in dingo scats collected from our study site showed European rabbits Oryctolagus cuniculus dominated their diet, which was mirrored in a meta-analysis of the diet of dingoes across the 5.4 million km2 arid zone. Whenever food availability boomed during resource pulses, hyperabundant small and medium sized mammals became their primary prey. Dingoes showed considerable dietary similarities throughout the arid zone, despite some sites being separated by a distance equivalent to that between Spain and Russia. Using captive dingoes fitted with accelerometers, we developed a classification model that predicted 14 behaviours from accelerometry data collected at the very low frequency of 1 i Hz. The high accuracy (mean = 87%) of these predictions, even at a low sampling frequency, suggests that reliable, fine-scale behavioural observations of wild animals can be made over a longer period than was previously thought possible. To investigate resource use at both the individual and population level, we obtained > 150,000 GPS locations from 18 dingoes over a two year period. At the population level, dingoes selected strongly for watercourses and avoided salt lakes, which is not surprising considering the survival of canids in desert ecosystems is contingent upon access to free water and refuges. Interestingly, there was extreme individual variation in space use by dingoes, as well as seasonal differences in activity patterns where females shifted their behaviour from crepuscular to diurnal during the pup whelping and rearing seasons. We recorded accelerometry data from seven wild dingoes, and were able to apply our classification model to predict fine time-scale behaviours. We then used these behaviours to create activity-specific time-energy budgets by incorporating energetic data previously reported in the literature. This is one of the first attempts at integrating location, accelerometry, and energetic data, and allowed the comprehensive assessment of the daily costs of living in a wild canid. Our results revealed that ambient temperature (Ta) drives the activity and energetics of dingoes in the arid zone, with substantially lower activity when external temperatures were high, equating to lower daily energy expenditure in summer than in winter. Moreover, the negative relationship between dingo activity and Ta during the day implies that high heat gain from solar radiation is a factor that limits diurnal activity in an arid environment. ii Thesis Declaration I certify that this work contains no material which has been accepted for the award of any other degree or diploma in my name, in any university or other tertiary institution and, to the best of my knowledge and belief, contains no material previously published or written by another person, except where due reference has been made in the text. In addition, I certify that no part of this work will, in the future, be used in a submission in my name, for any other degree or diploma in any university or other tertiary institution without the prior approval of the University of Adelaide and where applicable, any partner institution responsible for the joint-award of this degree. I acknowledge that copyright of published works contained within this thesis resides with the copyright holder(s) of those works. I also give permission for the digital version of my thesis to be made available on the web, via the University’s digital research repository, the Library Search and also through web search engines, unless permission has been granted by the University to restrict access for a period of time. I acknowledge the support I have received for my research through the provision of an Australian Government Research Training Program Scholarship. Sincerely, Jack Tatler iii Acknowledgements Well, what a journey. The very first person who needs acknowledgement is Shannon Currie. Thank you for your unwavering support and encouragement, your brain and your friendship every single day throughout this rollercoaster ride. I would be in a straitjacket if it were not for you. Thanks for my forever motto: ‘The early dingo catches the rabbit’. Phill Cassey and Thomas Prowse, I honestly lucked out with having you both as supervisors. I have learnt so much more than I thought possible thanks to your scientific minds. I hope I can continue to learn from you both in the future. Now let’s go have a beer! David Roshier, simply put, this entire project would not have happened if it were not for you. Who would have thought that helping a friend return duck traps would eventuate in a PhD on dingoes in arid Australia. Thank you for being a consistent support throughout the past four years and for helping me build strong relationships within the AWC. I should probably thank you more for your patience with my stroppiness, I feel you dealt with it more than anyone. Massive thanks to all of my colleagues who helped me trap dingoes and survive Kalamurina: Hannah Bannister, Mannie Fischer, Murray Schofield, Keith Bellchambers, Casey O’Brien, Mark and Tess McLaren. My lab mates Sarah Heinrich and Talia Wittmann, you made daily lab life not only bearable, but enjoyable. Thank you to my