Protecting white-clawed crayfish at Calke Abbey

Published:: 17 September 2023

Close-up of a white-clawed crayfish in a hand — White-clawed crayfish at Calke | © National Trust/Dennis Richardson

Last week over 600 white-clawed crayfish were collected from Calke Abbey in Derbyshire and relocated to an Ark site. Working alongside Derbyshire Wildlife Trust and partners, the translocation is part of ongoing conservation efforts to safeguard the future of this endangered native species.

White-clawed crayfish have sadly been in decline since the 1970s, due to the invasion of the non-native American signal crayfish. Signal crayfish are bigger and stronger than the white-clawed and can feed them, out-compete them for homes and food, and carry a fatal disease to the UK species, known as crayfish plague.

The Calke Abbey estate is approximately 1,000 hectares in size, made up of woodland, wood pasture, hay meadows, wetlands, and tenanted farmland. The Calke ranger team have managed this historic landscape to support an array of different wildlife, including the newly reintroduced rare hazel dormice. Click here to find out more about this conservation project.

Countryside Manager, Jon Lewney says: ‘Calke Abbey’s brooks contain a healthy population of white clawed crayfish. This gives us the opportunity to support the efforts to conserve this threatened species, by moving some of them to other sites. Establishing populations free from the invasive signal crayfish in as many places as possible is the best way to ensure our native crayfish survive.’

A women volunteer picking up a white-clawed crayfish and placing it in a bucket — Collecting white-clawed crayfish | © National Trust/Steve Franklin

Before being collected and transported, health checks were performed and eDNA sampling was carried out by the Environment Agency to ensure there were no signs of crayfish plague or American signal crayfish.

Calke’s brooks were then drained and redirected downstream for a short period to entice the white-clawed crayfish out of their burrows. The crayfish were then collected, examined, and transported to a safe location, where it is anticipated the crayfish will thrive.

White-clawed crayfish have also been found in lakes at Kedleston Hall. Click here to find out more.