Translocation is an important conservation intervention to restore small and declining or locally extinct populations. Individual behavioural variation influences the ability of translocated animals to adapt to novel environments following release. These individual differences have a particularly pronounced effect during early establishment phases where small populations amplify the impact of individual performance. Consequently, selection of animals is a key translocation tactic that can influence outcomes, yet few studies have related prerelease metrics to postrelease performance. Furthermore, survival rates and their drivers may change over time as founders move through postrelease behavioural modification phases. Here we used a pilot translocation of bush stone-curlew, Burhinus grallarius , to test which traits predict postrelease survival. The combined effects of sex and weight were the best overall predictors of survival, with males having better survival odds than females, and heavier females being more likely to survive. Given the species is monogamous and equal sex ratios are therefore needed to maximize population growth potential, reinforcing releases may need to prioritize females to compensate for this attrition. Latency to reach food weakly predicted short-term survival (to 90 days) but had no relationship with longer-term survival (to 1 year). Time spent alert, the most intensive assay to perform, had no predictive power. Handling response showed potential value as a predictor, with complete survival to 1 year in one behavioural category and complete mortality in another; however, inference was limited by the small sizes of these groups. Although statistical power was insufficient to confirm temporal shifts in survival predictors, we propose the following as a testable hypothesis for future translocation studies: behavioural predictors of survival vary with time postrelease. This study contributes to a growing body of knowledge on how to screen for release candidates based on individual traits. • Founder selection can improve translocation outcomes. • We investigated individual differences in translocated bush stone-curlews. • Sex and weight interactions were strongest predictors of survival. • Latency to reach food predicted short-term but not long-term survival. • Temporal shifts in trait predictors warrant further investigation.
Rapley et al. (Fri,) studied this question.