Fire and Fragmentation Interactions: Effects on Reptiles and Small Mammals in Modified Semi-Arid Landscapes
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Fire and fragmentation interactions: effects on reptiles and small mammals in modified semi-arid landscapes Moloch horridus – juvenile Thorny Devil Juliana Lazzari Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy of the Australian National University October 2019 Declaration This thesis is my own work, except where otherwise acknowledged (see Preface and Acknowledgements). Juliana Lazzari October 2019 iii PREFACE This thesis consists of four connected papers that present research I undertook for my doctoral program (Papers I-IV). The papers are framed by a brief Context Statement and Synthesis that explain the relationships between the papers and place my thesis in a broader ecological setting. One paper has been published (Paper II) and the remaining papers (Papers I, III and IV) have been prepared for publication, but not yet submitted. The papers were written to stand alone and for this reason there is some unavoidable repetition between them, for example in the background information and the description of study areas. References have been provided at the end of each paper, and a complete reference list is provided in the Consolidated Thesis References section at the end of this document. I designed my research agenda in consultation with my supervisor, Don Driscoll, to ensure my project targeted specific fire and fragmentation interaction research within the framework of a broader project on the fire ecology of plants, birds and reptiles. The overarching study was funded predominantly by an Australian Research Council grant to Don Driscoll. I performed the majority of the work for the papers that form this thesis, including developing research questions and experimental designs, conducting the field work for data collection and organised teams of volunteers to assist me. I also undertook the majority of work on the papers including literature searches, data analysis and writing the manuscripts. However, at each, but different, stage of the design, execution and write up of research, my supervisors (Don Driscoll, Chloe Sato, David Keith and Sam Banks) provided advice on how to conceptualise and interpret the findings, and also assisted with the revision of manuscripts. My statistical advisor (Hwan-Jin Yoon) provided expert advice for data analysis for the fire prediction paper. Where there are co-authors in each papers who are not listed as my supervisor, this reflects contributions from collaborators. All other contributions made to the work in this thesis are presented in the Acknowledgements section of each paper. v Paper I: Lazzari, J., Sato, C. F., Keith, D. A. and Driscoll, D. A. Does fire interact with habitat fragmentation to accelerate biodiversity loss? A systematic review. In Prep. for submission to Journal of Applied Ecology. Paper II: Lazzari, J., Yoon, H. J., Keith, D. A. and Driscoll, D. A. Local environmental covariates are important for predicting fire history from tree stem diameters. International Journal of Wildland Fire, 24(6): 871-882. Available at: https://doi.org/10.1071/WF15069 Paper III: Lazzari, J., Sato, C. F., Driscoll, D. A. Fire and fragmentation interactions affect reptile persistence in an agricultural matrix and conservation reserve. In Prep. for submission to Landscape Ecology. Paper IV: Lazzari, J., Sato, C. F., Banks, S. C., Driscoll, D. A. Does patch isolation affect small mammal occurrence and abundance after experimental fire in a fragmented landscape? In Prep. for submission to Biological Conservation. vi ACKNOWLEDGEMENTS My sincere thanks go to supervisors, project collaborators, to the many fieldwork volunteers and Fenner people who provided valuable program and project level support and contributions. Don Driscoll and Chloe Sato warrant particular mentions. Don didn't give up on me, and Chloe took a genuine interest in my work and brought me out of an isolated state that nearly did not see me complete this awesome project – your involvement cannot be overstated. The effective way that Chloe managed to get Don and me on track for the final stages of this project was nothing other than impressive! I am grateful to David Keith, Hwan-Jin Yoon, Samuel Banks, Martin Westgate, Steve Dovers and Saul Cunningham who provided very welcome intellectual and essential administrative contributions at different stages of my PhD. My close friends, who are in essence my family, both inside and outside of academia deserve a big upfront thank you. Fintán Ó Laighin has always shown unwavering faith in my ability to undertake and complete this project. Without his unconditional support, I would not have been able to 'climb to the top of this mountain'. Kirstie Rea has non-judgingly always just been there. Special thanks go to the people who I share a breadth of relationships and who helped me arrive at this pointy end - Annabel Smith, Kevin Mayes, Rosy Lazzari, Ann Holden, Suzi Bond, Shana Nerenberg, Brett Howland, Pia Lentini and Ingrid Stirnemann. Welcome sustenance was provided at critical times by Fintán, Kirstie, Katrina Wotton and Nicole Cosgrove. I thank the generosity of landholders who allowed me to survey their properties and use their homesteads as field bases – Judy and Frank Schaefer, Deb and Trevor Larwood, Jussy and Nick Lienert, Wes Matthews, Henry and Graham McKenna, Phil McKenna, Sandy and Olly Olsen, Jo and John Schaefer, Lisa and Terry Schmucker, Dean Willmott, and Mel and David Woolford. Lyla Francis and the Friends of Kimba District Parks deserve a big thanks for providing both cheerful friendship and local knowledge. vii I am grateful to over 30 people who happily volunteered to help me collect data in very challenging field conditions – Kevin Mayes, Lachlan Baird, Hannah Brugman, Rebecca Clemas, Katina Croft, Mitchell Doughty, Amanda Edworthy, Caren Elliott, Glen Ewers, Hugh Gardner, Patrick Gregson, Tim Groves, Peta Haesler, Carly Humphrys, Angus Kennedy, Tess Kolaric, Rosy Lazzari, Ollanta Lipcer, Amy Macris, Prashanth Magandram, Nicholas Mikhailovich, Matte Montesin, Fintán Ó Laighin, Jenna Olovic, Nikki Payne, Jesse Percival, Kirstie Rea, Annabel Smith, Coralie Tate, Mailyn Thomas, Anni Walsh, Catherine Whitehead and Joel Williams. The South Australian Department of Environment and Natural Resources (DENR) helped me with access to field sites and research permits. Special thanks to Joe Tilley from the Port Lincoln branch for his support and expertise in undertaking the essential project burns. Funding and in-kind support was provided by: an Australian Postgraduate Award; the Australian National University; Deakin University-Burwood; and personal savings. The study was supported by funds from the Australian Research Council and conducted under DENR scientific permit K25737 and animal ethics permits 26/2009-M1 (Government of South Australia) and S.R.E.09.09 (Australian National University). At a personal level, I expected to be challenged by undertaking such a large project, but I had not expected life's continuous curve balls that strongly tested the bounds of my sanity! Combining both academic and life challenges during my PhD certainly helped exceed my expectations of what I could achieve and overcome while under significant duress and living below the poverty line particularly for such a long period. And last but not least, thanks to Thea Lazzari, May Lyons, Des Lyons, Orlando Lazzari and Mark Lazzari – many of you were there at the beginning of my PhD, but all of you are now just strong memories, I thank you for helping me distinguish between the priorities that are truly important in my life. Patting 'tolls' for Cookie, Mickey, Florence, Eddie, Bessie and Shadow provided welcome moments of micro-relaxation relief. Simply put – grazie! viii ABSTRACT Interactions between fire and fragmented landscapes could be a primary factor influencing the distribution and persistence of species. However, historical and recent land use change and land management practices have altered the spread, frequency and intensity of fires globally. This presents a major challenge to biodiversity management because ecosystems are being modified by fire in already fragmented systems. Within fragmented fire-affected landscapes, the use or suppression of fire can provide successional habitats for a range of biota. However, records of fire history that are essential for managing fire-sensitive species, are often limited for many reserves and for remnant patches on private land. In addition, little is known about how reptiles and mammals use fragmented fire-affected landscapes, nor the role of reserves and remnants in mediating the interacting effects of these two major disturbances on co-occurring species. Due to this gap in understanding biodiversity responses to fire in fragmented landscapes, inappropriate fire regimes in such landscapes could lead to species losses. My aim was to understand species responses to interactions between experimental fire and habitat fragmentation in an agricultural matrix. To achieve this, I conducted studies that specifically addressed: 1) the current status of research, 2) how to build on current knowledge to predict fire age, 3) reptile trait responses, and 4) how small mammals are affected. For study 1) I undertook a systematic review of the literature that discusses the fire-fragmentation interaction effects on biodiversity. For study 2) I developed a model to predict fire age using environmental covariates and stem diameters. For studies 3) and 4), I undertook a natural and manipulative experiment using fire in remnants