Race against time to save Endangered native crayfish - Buglife

As invasive American Signal Crayfish numbers surge at a Derbyshire site, a bold rescue mission gives the UK’s White-clawed Crayfish a fighting chance – thanks to a new “Ark site” in Staffordshire.

The White-clawed Crayfish (Austropotamobius pallipes) is the UK’s only native crayfish species, and it is under serious threat.

Conservation efforts have intensified at a site in Derbyshire following a dramatic increase in invasive American Signal Crayfish (Pacifastacus leniusculus). The invasive species outcompetes and preys on White-clawed Crayfish, and also carries crayfish plague (Aphanomyces astaci) – a disease lethal to the native “White-claws” that can wipe out entire populations within weeks.

The rescue operation

A previous rescue operation successfully removed 60 native White-clawed Crayfish from the Derbyshire site. But when teams returned, they found the situation had worsened significantly.

During a follow-up visit in December, conservationists found “berried” females – crayfish carrying eggs – alongside three further American Signal Crayfish. The berried females were carefully transferred to Birmingham Sea Life Centre, where they were kept in quarantine and given thorough health checks.