Invertebrates
White-clawed Crayfish
Austropotamobius pallipes · also called Atlantic stream crayfish
Under a flat stone in a clear chalk stream, a white-clawed crayfish waits for dusk, the last of a native species that once filled the rivers of Britain.
Overview
The white-clawed crayfish, Austropotamobius pallipes, is an Endangered freshwater crayfish of clean, hard-water streams in Britain, Ireland, and western Europe. Its small size, pale claws, and vulnerability to plague make it one of the most threatened invertebrates of European rivers.
A native overwhelmed by invaders
The arrival of American signal crayfish, which carry a plague that does not harm them but kills the native species, has driven the white-clawed crayfish out of most of its former rivers.
Status
Endangered, declining across its range.
White-clawed Crayfish: common questions
Why is the white-clawed crayfish endangered?
It has been wiped out by crayfish plague carried by introduced American crayfish, and has also suffered from competition, pollution, and habitat loss.
Is it the only crayfish native to Britain?
Yes, it is the only crayfish native to Britain.
When is it active?
It hides in holes and under stones in the day and comes out to forage after dark.
Where is the white-clawed crayfish found?
It lives in clean, hard-water streams and rivers with stony beds in Britain, Ireland, and western Europe.