Journal article

Contraception of prepubertal young can increase cost effectiveness of management of overabundant koala populations

Emily F Hynes, Geoff Shaw, Marilyn B Renfree, Kathrine A Handasyde



Context: With limited resources for wildlife management and conservation, it is vital that the effectiveness of management programs is maximised and costs reduced. Koala populations need to be reduced in locations where they are locally overabundant and over-browsing their food trees. Subcutaneous contraceptive implants containing levonorgestrel are currently used to control koala fertility to assist in reducing population densities. Dependent young are caught with their mothers, so are also available for contraception. Aims: The overall aim was to investigate whether the effectiveness of koala contraception programs can be improved by administering levonorgestrel implants to female young al..

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Funding Acknowledgements

We thank the Parks Victoria rangers on French Island (M. Douglas, A. Ledden, T. Easy, S. Coutts, D. Stephenson, D. Jackson, G. Briggs) who provided transport and accommodation and were of great assistance in the field. We thank Parks Victoria personnel at Budj Bim National Park for allowing access to back young during their management program in 2017. We thank Leiras Pharmaceuticals, Finland and Professor R.V Short for the gift of the contraceptive implants. We thank two anonymous reviewers for their helpful comments that improved this manuscript. This study was supported by a grant from the San Diego Zoological Society, who with The University of Melbourne jointly funded a Ph.D. scholarship for EFH.