The white-clawed crayfish (Austropotamobius pallipes) is not technically a fish but a crustacean.
"They are nocturnal creatures and aren’t very active during the winter, which means that this secretive invertebrate is rarely seen."Carl Nicholls, fisheries & angling manager
Status: listed as Endangered on the International Union for Conservation of Nature (IUCN) Red list of Threatened Species
Typical size: maximum 12cm, typically 6-8cm.
Lifespan: 12 years
The white-clawed crayfish is the UK’s only native crayfish species - the white-claws originate from the UK whereas other crayfish species have been introduced from other countries. Since the 1970s there has been more than a 50% decline in the areas where white-claws occur in England and Wales and they are still declining rapidly.
Appearance: the white-clawed crayfish is one of our largest freshwater invertebrates growing up to 12cm long. They are omnivorous, so not fussy eaters and eat everything from other invertebrates to carrion and water plants.
White-claws have large pincers (claws) that are coloured cream or rosy white on their underside, and it is these distinctive claws which have given white-claws their name.
The carapace is generally brown to olive in colour with a pitted appearance. However, all colour variations have been observed, including blue and red white-claws.
They are nocturnal creatures and aren’t very active during the winter, which means that this secretive invertebrate is rarely seen. They have important roles in the freshwater environment because of their diet as well as providing food for other animals such as fish, herons and otters. They are also important indicators of good water quality as they are intolerant of pollution.
White-claws are found in rivers, streams, lakes and canals and prefer clean mineral rich waters.
Last date edited: 3 September 2015