Water crowfoot

American Signal Crayfish

September 25, 2015

Found throughout England, these 15cm long beasts are aggressive, breed faster than the native species, and damage banks with their burrowing

White-clawed crayfish, which are native to the UK, are now seriously endangered, thanks to the spread of their cousins from across the pond – the much larger and more aggressive American signal crayfish.

American signal crayfish (Pacifastacus leniusculus) not only drive out native white clawed crayfish as they compete for food and habitat, but also carry a water-borne fungus which is fatal to our native species. It is predicted that white clawed crayfish could become extinct in the UK within decades if efforts are not made to protect them.