Handling-related tail loss in an endangered skink: incidence, correlates and a possible solution M. P. Scroggie & N. Clemann Department of Sustainability and Environment, Arthur Rylah Institute for Environmental Research, Heidelberg, Vic., Australia Keywords animal welfare; caudal autotomy; Cyclodomorphus praealtus; generalized additive model; skink. Correspondence Michael P. Scroggie, Department of Sustainability and Environment, Arthur Rylah Institute for Environmental Research, PO Box 137 (123 Brown St), Heidelberg, Vic. 3084, Australia. Email: michael.scroggie@dse.vic.gov.au Editor: Tim Halliday Received 28 July 2008; revised 7 October 2008; accepted 8 October 2008 doi:10.1111/j.1469-7998.2008.00528.x Abstract Caudal autotomy (tail loss) during capture and handling is widely reported among several families of lizards. Autotomy causes elevated stress levels in lizards, and imposes a significant fitness cost on autotomized individuals. Despite these detrimental impacts, conservation and ethical issues associated with handling- related tail loss have received little attention. We assessed the incidence and correlates of tail autotomy during capture and handling in an endangered skink, the alpine she-oak skink Cyclodomorphus praealtus. A significant proportion (9.3%) of lizards autotomized their tails during capture and handling. Medium- sized lizards were more likely to lose their tails during handling, and this effect was exacerbated at intermediate body temperatures. Probability of autotomy had a complex relationship with cumulative observer experience, independent of other risk factors. Based on the modelled relationship of autotomy with body tempera- ture, we propose that alpine she-oak skinks be cooled immediately after capture to reduce rates of autotomy during subsequent handling. Introduction Caudal autotomy (tail loss) by lizards during capture and handling by researchers is a widely reported phenomenon among several families of lizards (Clause & Capaldi, 2006; Webb, 2006). The biological aspects of the process of tail autotomy have received considerable attention from re- searchers, with an extensive literature on the physiological, ecological and evolutionary consequences of this mechan- ism (Arnold, 1984; Cooper, Pe´rez-Mellado & Vitt, 2004; Clause & Capaldi, 2006; Maginnis, 2006). In contrast, the conservation, ethical and animal welfare implications of tail loss inadvertently caused during capture and handling of lizards by researchers, have received comparatively little attention (Langkilde & Shine, 2006). Tail autotomy causes significant fitness costs to lizards, in the forms of reduced survival (Niewiarowski et al., 1997), fecundity (Chapple, McCoull & Swain, 2002), mating suc- cess (Martin & Salvador, 1993), growth (Ballinger & Tinkle, 1979), locomotor performance (Chapple & Swain, 2002) and social status (Wilson & Booth, 1998). As a consequence, elevated rates of tail loss caused by researchers could adversely affect the status of threatened species. In addition to the ecological consequences of tail loss, tail autotomy can cause an increase in levels of plasma corticosterone in lizards, consistent with a physiological stress response (Langkilde & Shine, 2006). Evidence of reduced fitness and physiological stress caused by handling-induced tail autot- omy raises clear ethical and animal welfare implications that should be considered by researchers carrying out procedures that may result in deliberate or incidental tail autotomy (Langkilde & Shine, 2006). While conducting a project to assess the distribution, habitat associations and conservation status of the alpine she-oak skink Cyclodomorphus praealtus within the state of Victoria, Australia, we observed that a significant propor- tion (9.3%) of captured individuals autotomized their tails during routine handling. In this paper, we use our observa- tions of autotomy during capture and handling to quantify the risks of handling-related tail autotomy. We use statisti- cal models to explore possible biological, environmental and human influences on the probability of tail autotomy during capture and handling, and explore ways in which rates of autotomy can be reduced. Methods Lizard capture and handling The alpine she-oak skink is a medium-sized scincid [up to 126 mm snout–vent length (SVL), authors’ observations], with a relatively short tail compared with its congeners: Shea (1995) reported a mean tail length/SVL ratio of 0.673 Journal of Zoology Journal of Zoology 277 (2009) 214–220 c  2009 Department of Sustainables and Environment, Victoria. Journal compilation c  2009 The Zoological Society of London 214 Journal of Zoology. Print ISSN 0952-8369