White-clawed crayfish breedingtanks. Photograph by the
Environment Agency.
Why was there a need for the project?
White-clawed crayfish (WCC) is a UK BAP species and classed as Globally Threatened by IUCN. It is the only species of freshwater crayfish which is native to the UK, and it is thought that the UK supports around a quarter of the world's population of WCC. They have declined due to pollution, the invasion of the North American signal crayfish and crayfish plague.
What are the projects aims?
The project aims to further the conservation of WCC in Ribblesdale, and to develop conservation measures that may be applied elsewhere. Phase 1 was an attempt to eradicate signal crayfish recently found at the headwater of a small Yorkshire Dales beck. Following initial investigations, it was decided that a biocide eradication attempt could not be taken forward within the timescale of the current project. Phase 2 has five elements: eradicating crayfish plague in Ling Gill National Nature Reserve; a captive breeding programme; identifying and monitoring potential ‘ark’ sites; evaluating the ecological requirements for successful reintroductions; and education and awareness raising.
What has the project achieved so far?
The installation of four temporary weirs was found to be very effective in severely limiting the downstream movement of WCC into the plague-infected zone. Based upon the first summer’s monitoring, it is possible that the crayfish plague has already been eradicated.
A captive breeding facility has been set up in Ribblesdale. It comprises of a series of online tanks, fed from a header tank of springwater from the base of a limestone escarpement. The project is the most successful breeding facility in the UK. Three generations of white clawed crayfish have been raised. It has created an arc facility, to secure the species until signal crayfish and plague can be eradicated and white clawed crayfish can be reintroduced to rivers in the area.
Two new posters have been designed to assist in awareness-raising works, and three trial WCC awareness-raising set-ups have been established (Field Studies Council - Malham, Horton-in-Ribblesdale School and a Leeds school).
Who is involved?
The project partners are the Yorkshire Dales National Park Authority, Yorkshire Dales Millennium Trust, the Environment Agency, and Paul Bradley Associates. The project has had significant volunteer input and supported by local farmers, the Manchester Anglers Association and Natural England.
Further information:
Contact:
Paul Bradley (Paul Bradley Associates)
Telephone: 0114 2681684,
Email: p.bradley@bioscape.co.ukNeil Handy (Environment Agency)
Email: neil.handy@environment-agency.gov.uk
