Efforts to protect the UK’s only native species of crayfish have seen almost 600 specimens moved to protected new homes in Lincolnshire.
The endangered white-clawed crayfish have been transferred to two secluded locations, chosen for their potential as safe havens.
Known as ‘Ark Sites’, the carefully selected refuges have all the characteristics needed for the crayfish to establish a thriving colony, including good-quality water, suitable habitat, and an isolated location.
Most importantly, they will be safe from the threat of their non-native counterparts, the North American Signal crayfish.
This invasive species out-competes our own for food and habitat, and carries a fungal disease that devastates native populations.
Dr Chris Extence, Environment Agency team leader for Analysis and Reporting, said: “Bringing our native crayfish into the safety of an Ark Site is vital to protecting them from these threats, safeguarding their long-term survival and stability.”
White-clawed crayfish are the only native species of crayfish in Britain. Although protected by law, numbers have declined dramatically in recent years and established populations are becoming increasingly vulnerable.
In Lincolnshire, the Upper Witham has long been a stronghold for native crayfish, but they are increasingly under threat from Signals. In total, 572 specimens were moved into two undisclosed locations in Lincolnshire two weeks ago: a limestone stream in the county’s south west and a chalk stream in the Wolds.
“In the case of the latter, this is the first time in many years that this Area of Outstanding Natural Beauty has been home to native crayfish,” said Dr Extence.
A number of organisations, including the Environment Agency, Natural England, Lincolnshire Rivers Trust, Lincolnshire Wildlife Trust and Lincolnshire Chalk Stream Partnership, were involved in the two-day operation.
Environment Agency specialists will now monitor the colonies in their new homes.
Dr Extence said: “The use of Ark Sites is nationally-recognised best practice, and just one of the ways we can safeguard the future of the native crayfish.
“A previous attempt at creating an Ark Site in Lincolnshire has been successful, with evidence of breeding – a strong sign of an established colony.”