Farnsworth et al. (2015) and Brand et al. (2016) documented short-term effects on the movement and thermal conditions of tortoises that were translocated as part of this study. Their findings indicated that in the initial two months of the first active (i.e., non-hibernation) season post-translocation, translocated tortoises had larger home ranges, exhibited lower space use intensity (i.e., movement behavior that was less concentrated in a particular location), and experienced higher ambient temperatures than did resident and control tortoises. However, space use and thermal conditions of translocated tortoises were indistinguishable from those of control and resident tortoises thereafter (Farnsworth et al. 2015; Brand et al. 2016). Based on these findings, we hypothesized that there may have been similar short-term effects on the survival of translocated tortoises, although previous studies did not analyze survival.Here, we present results of known-fate survival models designed to document post-translocation survival and identify potential individual and environmental drivers of variation in tortoise survival over a five-year period between May of 2012 and May of 2017. Five broad biological and physical factors were hypothesized to influence survival (United States Fish and Wildlife Service 2011): weather (precipitation and temperature), disease, vegetation, physical features (e.g., soil and topography), and anthropogenic impacts (e.g., environmental toxicants, barriers to movement). The relative manner in which these drivers impact survival—either through direct effects on tortoise populations or as interacting effects working in concert—remains uncertain, but should be accounted for when isolating the effects of translocation from other potential drivers of survival. Therefore, we included relevant variables in all of these categories in the survival analyses presented below, with the exception of disease. We examined tortoises for evidence of disease and bacterial infection (Jacobson et al. 2014), but there were too few positive tests to yield sufficient power to detect survival differences (see Dickson et al. (2017)) so those data are not presented here. The primary aims of our study were: (1) to test whether translocated tortoises had lower survival than control and resident tortoises, and, if so, over what timeframe, and (2) to examine the impact of individual and environmental covariates hypothesized to influence tortoise survival, specifically testing whether they had a differential effect on tortoises in the three treatment groups.

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