Welfare considerations during a conservation translocation of white-clawed crayfish ( Austropotamobius pallipes ): Proof of concept

Abstract Translocations are a conservation method used to establish or supplement self-sustaining populations. However, research regarding the welfare implications of this strategy is limited, particularly in recipient wild populations. Introductions of captive-born individuals are commonly used to supplement populations of endangered white-clawed crayfish ( Austropotamobius pallipes ), the UK’s only native crayfish species. To determine effects of translocation, both introduced and wild crayfish were marked and PIT-tagged, then monitored through behavioural observations and body condition scoring. We undertook analysis on welfare indicators, comparing resident and captive crayfish, as well as resident crayfish pre- and post-introduction. Our results provide some evidence that translocation events alter behaviour of resident crayfish. We also found some evidence that wild and captive-born crayfish differ in behaviour, with potentially negative welfare implications. By contrast, body condition analysis showed no variation pre- and post-introduction, suggesting that captive-born crayfish can effectively adapt to natural environments. Some behavioural differences were also better explained by other predictors rather than origin of animal. Multiple influences on the behaviour of crayfish were identified, including sex and weather conditions. Moreover, we identified factors which could enhance the welfare of this species in captivity and increase translocation efficacy, such as replicating features of natural environments in hatcheries. We also establish a basis for future research which could enhance conservation and understanding of the species.