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Evolutionary, molecular and comparative zoology
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RESEARCH ARTICLE
Contents Vol 56(6)

Age structure, mortality and breeding in a population of agile wallabies (Macropus agilis)

Simon C. Stirrat
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Faculty of Science, Information Technology and Education, Charles Darwin University, Darwin, NT 0909, Australia. Present address: Environmental Protection Agency, GPO Box 2771, Brisbane, Qld 4001, Australia. Email: simon.stirrat@epa.qld.gov.au

Australian Journal of Zoology 56(6) 431-439 https://doi.org/10.1071/ZO08060
Submitted: 16 July 2008  Accepted: 14 January 2009   Published: 18 March 2009

Abstract

Aspects of the demography of the agile wallaby (Macropus agilis) were investigated in an overabundant population in East Point Reserve, Darwin. The maximum wet-season population size was relatively stable for several years before, and during, this study. Data suggest that the population fluctuated in size seasonally. Life table analysis indicated that mortality of animals up to 18 months old (including pouch young and young-at-foot) was high compared with adult mortality rates. After 18 months of age, mortality rates of males increased throughout life whereas those of females declined slightly and were relatively stable in older age classes. Females reproduced throughout the year, but more large pouch young were observed in the wet season than at other times of the year. The sex ratio of the population was female-biased, probably a result of higher mortality of males in the dry season. Predation by dogs was documented but contributed a relatively small fraction of total annual mortality.


Acknowledgements

I thank Dr Gordon Duff, Dr Keith McGuinness and Dr Peter Whitehead for assistance with data analysis and writing of this work. I thank the Darwin City Council for providing funding for this research. The assistance of numerous Darwin City Council staff, including Bob Morgan, George Rosenkranz, Mark Presswell and Rob Keeley is also greatly appreciated. I also acknowledge the valuable contribution of anonymous referees in preparation of the manuscript.


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