Crayfish Surveys
White-clawed crayfish are our only native freshwater crayfish. Numbers in Britain have declined dramatically since the 1970’s, partly due to agricultural practices and watercourse management change, but largely as a result of competition from the introduced North American signal crayfish and the ‘crayfish plague’ which this species carries. The white-clawed crayfish is encountered with decreasing regularity in rivers, streams, lakes and canals. Isolated “Ark” sites are now being established by conservationists in places such as former mineral sites to act as refuge sites and to provide a potential source for future reintroductions.
Whilst individual crayfish and their habitat are not specifically protected, it is illegal to commercially harvest them. EU member states are also required to designate Special Protection Areas (SPA’s) for important populations under the Habitats Directive. The white-clawed crayfish is also a Priority species in the UK Biodiversity Action Plan and is listed as a Species of Principal Importance in England under Section 41 of the NERC Act 2006.
CSa can provide white-clawed crayfish surveys to determine the presence or absence of this sensitive species. Site-specific crayfish mitigation requirements need to be determined where this species is found; preservation of suitable habitat during and after development is critical.
