Does translocation influence physiological stress in the desert tortoise?

Published source details Drake K.K., Nussear K.E., Esque T.C., Barber A.M., Vittum K.M., Medica P.A., Tracy C.R. & Hunter K.W. (2012) Does translocation influence physiological stress in the desert tortoise?. Animal Conservation, 15, 560-570.
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This study is summarised as evidence for the following.

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	Translocate adult or juvenile reptiles: Tortoises, terrapins, side-necked & softshell turtles Action Link

Translocate adult or juvenile reptiles: Tortoises, terrapins, side-necked & softshell turtles

A replicated, controlled, before-and-after study in 2007–2009 in four sites of desert scrub in California, USA (Drake et al. 2012) found that translocated desert tortoises Gopherus agassizii did not have elevated levels of stress hormone compared to wild tortoises. There were no differences in stress hormone (corticosterone) levels between translocated (males: 4–12 ng/mL; females: 3–12 ng/mL) and resident tortoises within release sites (males: 3–12 ng/mL, females: 2–10 ng/mL) or residents outside release sites (males: 3–10 ng/mL; females: 3–11 ng/mL), but overall stress levels did vary between years (2007: 4ng/mL; 2008: 9 ng/mL; 2009: 6 ng/mL). In March 2008, translocated tortoises (45 tortoises: 18 females, 27 males) were released into four areas (1.6 km² each) between 9–30 km from the point of capture. A further 179 tortoises (72 females, 107 males) resident in the translocated area were monitored that had home ranges within or outside of the release sites (numbers of each not provided). Levels of stress hormone were measured by taking monthly blood samples (1,793 blood samples in total) in April–October, 2007–2009 from translocated tortoises (19–43 individuals/year) and residents from within (34–43 individuals/year) and outside the release areas (19–48 individuals/year).

(Summarised by: Maggie Watson, Katie Sainsbury)