Effects of Translocation on Gopher Frog Survival and Movement

Abstract

Translocation is increasingly used to move animals of conservation concern away from sites where habitat will be destroyed (mitigation translocation), but outcomes have rarely been adequately monitored, particularly for amphibians. We used radiotelemetry monitoring to assess survival and movement of 23 experimentally translocated, adult Gopher Frogs (Lithobates capito) at a recipient site in north-central Florida, USA. Although posttranslocation monitoring was our primary goal, we also compared our results with those of 24 nontranslocated frogs that were monitored in three previous efforts, conducted at different locations and times. For both translocated and nontranslocated frogs, movement was the most important predictor of mortality, with translocated frogs having a significantly higher probability of movement and higher mortality during the first month following release. However, there was no effect of translocation on survival after controlling for probability of movement because movement was dangerous for both translocated and nontranslocated frogs. Movement by translocated frogs was likely a behavioral response to the translocation experience, whereas movement by nontranslocated frogs was associated with breeding pond visitation, which was not observed within the translocated group. Survival was high for both groups once they settled into underground refugia and movement declined. Despite the comparatively high mortality of translocated frogs immediately following release, more than half survived to the end of monitoring and remained in the vicinity of the release site, meeting an early benchmark of translocation success.