Release protocols and release environment: what influences reintroduction success for the brushtail possum? Hannah Lee Bannister The University of Adelaide School of Biological Sciences Department of Ecology and Environmental Science Thesis submitted for the degree Doctor of Philosophy January 2019 i 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 and Faculty of Sciences Divisional Scholarship. Signed: ________ ii CONTENTS Thesis declaration ....................................................................................................ii Contents ................................................................................................................. iii Publications .............................................................................................................. 1 Abstract .................................................................................................................... 2 Thesis objective ....................................................................................................... 3 Thesis aims .............................................................................................................. 3 1. Introduction .......................................................................................................... 4 1.1 Declines and extinctions ................................................................................ 4 1.2 Reintroductions .............................................................................................. 5 1.2.1 Problems with fences .............................................................................. 6 1.3 Study species .................................................................................................. 7 1.3.1 Conservation status ................................................................................. 9 1.3.2 Previous brushtail possum translocations ............................................. 10 1.4 Study area .................................................................................................... 13 1.5 Reintroduction of possums to IFRNP .......................................................... 15 2. Release methods ................................................................................................ 17 2.1 Contextual statement .................................................................................... 17 2.2 Statement of authorship ............................................................................... 18 2.3 Abstract ........................................................................................................ 19 2.4 Introduction .................................................................................................. 19 2.5 Methods ....................................................................................................... 20 2.6 Results .......................................................................................................... 24 2.7 Discussion .................................................................................................... 28 2.8 Acknowledgements ...................................................................................... 30 3. Previous exposure to predators .......................................................................... 31 3.1 Contextual statement .................................................................................... 31 3.2 Statement of authorship ............................................................................... 32 3.3 Abstract ........................................................................................................ 33 3.2 Introduction .................................................................................................. 33 3.3 Methods ....................................................................................................... 35 3.4 Results .......................................................................................................... 40 3.5 Discussion .................................................................................................... 44 3.6 Acknowledgements ...................................................................................... 47 4. Habitat ................................................................................................................ 48 4.1 Contextual statement .................................................................................... 48 4.2 Statement of authorship ............................................................................... 49 iii 4.3 Abstract ........................................................................................................ 50 4.4 Introduction .................................................................................................. 50 4.5 Methods ....................................................................................................... 52 4.6 Results .......................................................................................................... 57 4.7 Discussion .................................................................................................... 64 4.8 Acknowledgements ...................................................................................... 66 5. Diet ..................................................................................................................... 68 5.1 Contextual statement .................................................................................... 68 5.2 Statement of authorship ............................................................................... 69 5.3 Abstract ........................................................................................................ 70 5.4 Introduction .................................................................................................. 70 5.5 Study site ...................................................................................................... 71 5.6 Methods ....................................................................................................... 72 5.7 Results .......................................................................................................... 75 5.8 Discussion .................................................................................................... 79 5.9 Acknowledgements ...................................................................................... 82 6. Juveniles ............................................................................................................. 84 6.1 Contextual statement .................................................................................... 84 6.2 Statement of authorship ............................................................................... 85 6.3 Abstract ........................................................................................................ 86 6.4 Introduction .................................................................................................. 86 6.5 Materials and methods ................................................................................. 88 6.6 Results .......................................................................................................... 91 6.7 Discussion .................................................................................................... 99 6.8 Acknowledgments ..................................................................................... 102 7. General discussion ........................................................................................... 103 7.1 Contributions to knowledge ....................................................................... 105 7.2 Limitations ................................................................................................. 106 7.3 Future directions ........................................................................................ 107 7.4 Management implications .......................................................................... 109 7.5 Conclusions ................................................................................................ 110 8. Acknowledgements .........................................................................................