Narrow-clawed (Turkish) Crayfish

Introduced to the UK via fish markets in the 1970s, escaped individuals and deliberate wild releases have led to the expansion of populations in some locations in England. Successful breeding populations can be found in south-east England and at scattered locations in the Midlands. Preferentially found in still-water systems such as lakes and canals but have also been recorded in rivers. Narrow-clawed crayfish are also capable of tolerating higher saline environments and may allow them to take up a niche unoccupied by native crayfish populations.

This species is more aggressive than our native white-clawed crayfish and thus have the potential to outcompete them. However, narrow-clawed crayfish are also susceptible to crayfish plague and high levels of pollution.

Appearance: long, thin body green to brown in colouration and may be mottled. Distinctive long, straight claws.

• Vital that biosecurity is taken into account in survey design as there is the potential that individuals may be carriers of crayfish plague. Thoroughly disinfect all footwear/waders and equipment before entering the sampling site or moving between sites.