White-clawed Crayfish - Austropotamobius pallipes

Alt Name
Freshwater White-clawed Crayfish 
Description

The only freshwater crayfish native to the UK, this species is olive-green to brown in colour and can reach up to 12 cm in length. The common name refers to the fact that the undersides of the claws are off-white to pinkish in colour. Females tend to have wider abdomens than males, and males have larger claws.

Similar Species

Follow the attached link for comparison of Crayfish species http://www.boxvalley.co.uk/nature/fiss/General/crayfish.asp

Photo ID?
Habitat

Tends to prefer clear, well-oxygenated, alkaline water and occurs in small streams, lakes, rivers, water-filled quarries and reservoirs.

When to see it

All year round. This crayfish tends to be nocturnal.

Life History

Emerges at night to feed on a broad diet consisting of detritus, animal matter and plants. It also occasionally indulges in cannibalism, particularly on individuals with soft cuticles following their moult. In males, the first two appendages are specialised; they are used to place a sperm mass (spermatophore) underneath the female during mating. Mating takes place in autumn; the eggs develop whilst attached to the mother's abdomen, and the female overwinters with the eggs still attached to her. After the eggs hatch, the juveniles remain attached to the mother before becoming independent at the beginning of summer.

UK Status

Declining swiftly and threatened. Protected under Schedule 5 of the Wildlife and Countryside Act 1981.

VC55 Status

Although scattered populations still exist in Leicestershire & Rutland the numbers have declined in line with other areas of Britain.

Leicestershire & Rutland Map

UK Map