Using conservation translocations to assess the impact of anthropogenic climate change on a cold-adapted reptile, the tuatara (Sphenodon punctatus) Stephanie J. Price A thesis submitted to Victoria University of Wellington in fulfilment of the requirement for the degree of Doctor of Philosophy Victoria University of Wellington Te Whare Wānanga o te Ūpoko o te Ika a Māui 2016 Abstract Anthropogenic climate change is progressing at a rate unprecedented in the past 65 million years and is a significant conservation concern. The associated biotic and abiotic impacts are expected to have substantial effects on global biodiversity, with some species potentially more vulnerable than others. The tuatara (Sphenodon punctatus) is a New Zealand endemic reptile and of particular interest as it is a slowly reproducing, range- restricted, cold-adapted ectotherm with temperature-dependent sex determination. Consequently, tuatara could be particularly vulnerable to rising air temperatures and conservation translocations have been key components of tuatara conservation efforts. Knowledge of how the tuatara might be affected by warmer climates will help inform where future conservation efforts are best directed, practices to avoid and which sites might be most suitable for the establishment of populations. The translocation of 176 adult tuatara in October 2012 from Stephens Island in New Zealand’s Cook Strait to four latitudinally distant North Island sites offered the opportunity to study the responses of tuatara in a range of environments. The comparatively warmer, drier climates of several sites provided surrogates for temporal climate change, enabling an assessment of how a warming climate might impact tuatara, and how they might respond. Using field observations, laboratory analysis and controlled experiments I investigated the short- term success of the translocations, the influence of translocation and climate on tuatara enteric bacterial communities and parasites, as well as how warmer climates might influence nocturnal activity, thermoregulatory opportunities and learning ability. I found several translocated populations to be progressing favourably, and found evidence that tuatara may exhibit enhanced growth at warmer, less densely-populated sites, suggesting that further translocations to lower latitude sites might be a viable conservation strategy. However, high population density at one translocation site was a concern and management recommendations were made to enable the dispersal of individuals. I detected Salmonella Saintpaul for the first time in a live tuatara, Campylobacter spp. was identified as a likely common commensal organism, and no measurable impact of translocation or climate on bacterial prevalence was observed, suggesting no substantial risk of climate warming to the susceptibility of tuatara to these bacteria. Tick populations were negatively impacted by translocation-associated factors following release but i subsequently recovered at most sites and mites were not found on any translocated tuatara. Diurnal and nocturnal activities were positively influenced by air temperature, up to an upper threshold, and assessment of the site-specific thermal climates suggested that tuatara at warmer sites may benefit from increased opportunities for emergence and the attainment of preferred body temperatures throughout the year, though a higher frequency of restrictive air temperatures over summer may also reduce emergence opportunities. Experimental work showed that warmer air temperatures may enhance learning in tuatara, which could improve their ability to cope with challenging environments under climate change. However, body size was also an influential component of learning ability and further research is needed to build on these initial findings. I conclude that tuatara may experience overall benefits from further translocations to warmer sites and warming climates at currently cooler sites, which suggests that other cold-adapted reptiles with similar thermal tolerances may also see initial benefits under climate warming, though further monitoring is required to determine longer-term translocation success. Equally, while warmer air temperatures were not found to be detrimental to tuatara, they still pose a risk to population viability and further work is required on the impacts of associated abiotic factors like drought, and how populations of this long-lived species may be affected if and when climate warming exceeds the upper temperature rise of ~5oC predicted by the 2100s. ii Acknowledgements Firstly, I would like to thank my primary supervisor at Victoria University of Wellington, Nicola Nelson, who was willing to help me launch into the PhD application that brought me to New Zealand and provided advice and guidance throughout my studies. Kristine Grayson, of the University of Richmond, despite being a long-distance supervisor our Skype meetings and email exhanges were invaluable and I am thankful for her advice and meticulous feedback on numerous drafts. Brett Gartrell, of Massey University, whose knowledge, expertise and practical advice were always appreciated. I would also like to thank Nigel French, of Massey University, who welcomed me to the mEpiLab and facilitated research that would not have been possible for me otherwise. Also, Anne Midwinter, Patrick Biggs, Angie Reynolds, Zoe Grange, Lynn Rogers and everyone else at the mEpiLab who offered support, advice and assistance as I was learning the ropes. My thanks also go to the many people at Victoria University of Wellington who have supported me, distracted me, educated me and assisted me at one point or another. Sue Keall, who always had useful advice and practical know-how. My office mates, past and present, Patty Ramirez, Anna Carter, Helen Taylor, Vaughn Stenhouse, Lindsay Anderson, Rosalynn Anderson-Lederer, Evan Brenton-Rule and Zak Murray. I would also like to thank the friends I made here and who helped make Wellington a home, in particular Brit Finucci, Annie Galland and Laina Isler, who provided endless entertainment and encouragement. Much of my fieldwork would not have been possible without the assistance of numerous volunteers and sanctuary staff who, come rain or shine, spent their days and nights on site with me. Too many of you helped over the past three years to name you all here, but thank you. Special thanks go to Emma Dent, Francesco Civilini, Te Taiawatea Moko-Mead, Emma Rowell, Colin Thompson, Noela McGregor, Sarah Alexander, Rebecca Webster, Bart Cox, John Berry, Nick Cabot and Tamsin Ward-Smith. My thanks also to the staff at ZEALANDIA, Maungatautari Ecological Island, Cape Sanctuary, Ngā Manu Nature Reserve and Ecoworks New Zealand Ltd. Without the support of the Department of Conservation, iwi and landowners, who granted me access to the land and tuatara, none of this work would have been possible. I would like to thank Ngāti Kōata, Ngāti Mihiroa, Ngai Tāmanuhiri, the Wellington Tenths Trust, the Mana Whenua representatives for Maungatautari and Ngāti Porou. My thanks iii also go to all of the Department of Conservation staff involved in getting me to and from Whangaokeno and Stephens Island and the people who helped make my stays on these islands enjoyable ones, to Polly Hall and Hal Hovell in particular. Funding for my PhD research was provided by several organisations and I would like to express my gratitude to the Commonwealth Scholarship Commission and Victoria University of Wellington. I also received grants from the VUW Faculty of Science, the Allan Wilson Centre, the VUW Centre for Biodiversity and Restoration Ecology, the Australasian Society for the Study of Animal Behaviour and the Society for Research on Amphibians and Reptiles in New Zealand. This research was conducted with approval from the Victoria University of Wellington Animal Ethics Committee (Permit No. 2012R33) and the New Zealand Department of Conservation (Permit No. 36857-FAU). Final thanks are saved for my family and my partner Matt, to whom this thesis is dedicated. They supported and encouraged me in every way possible and I am unendingly grateful. I quite literally could not have done this without them. iv © S. Price 2014 © Price S. “There is a grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.” - Charles Darwin, On the Origin of Species v vi Table of contents Abstract …………………………………………………………………………………..……………………..……….i Acknowledgements ……………………………………………………………………………….…………….…iii Chapter One: Using conservation translocations to assess the possible effects of anthropogenic climate change on the tuatara (Sphenodon punctatus) ...................... 1 1.1 Climate change, dispersal, adaptation and phenotypic plasticity ........................... 1 1.2 The tuatara (Sphenodon punctatus) ..................................................................... 5 1.3 Translocation as a conservation tool .................................................................... 9 1.4 Bacteria: Commensal and potentially pathogenic microorganisms, Salmonella spp. and Campylobacter spp. ................................................................................................ 16 1.5 Parasites: ticks, mites, haemoparasites and intestinal parasites .......................... 19 1.6 Thermoregulation and nocturnal