The White-clawed Crayfish or Atlantic Stream Crayfish (Austropotamobius pallipes), is a European freshwater crayfish, and the only species of crayfish native to the British Isles. It is found from the Balkan Peninsula to Spain and reaches its northerly limit in Great Britain and Ireland, where it also has its greatest population density.
The distribution of A. pallipes is rapidly shrinking and in Great Britain it is now more or less restricted to central and northern England and eastern Wales, though there is a regionally significant population in the River Frome in South Gloucestershire and Bristol, and a population has been discovered in Essex. There is also a population in Candover Brook, a tributary of the River Itchen in Hampshire. However, it was once found across most of England and Wales.
It is an olive-brown color, with pale-colored undersides to the claws. It may grow to 5 inches long, although sizes below that are more common. It typically lives in rivers and streams about 40 inches deep, where it hides among rocks and submerged logs, emerging to forage for food, and also in lakes.