Cefas confirms crayfish plague in River Waveney

Scientists at Cefas (the Centre for Environment, Fisheries & Aquaculture Science) have confirmed that crayfish plague (Aphanomyces astaci) has recently caused mass mortalities of Turkish crayfish (Astacus leptodactylus) in the River Waveney, between Bungay and Lowestoft in Suffolk. The Environment Agency sent samples to Cefas’ laboratory in Weymouth, Dorset , for analysis and the results were confirmed today.

Crayfish plague is caused by a pathogen that was first introduced into the UK by the North American signal crayfish. Commercial fish farmers brought the signal crayfish to England during the 1970s. While crayfish plague does not kill North American crayfish species that carry the infection, it is lethal to the UK’s native, white-clawed crayfish and other European species, such as the Turkish crayfish.

Cefas’ Dr Birgit Oidtmann, an internationally recognised expert on crayfish plague, said: “The most likely route of introduction of crayfish plague into the River Waveney is via the introduction of North American crayfish. In the past, there have been cases of deliberate introductions of North American crayfish into other river systems, but introductions may also occur by accidental co-transport of North American crayfish during stocking events. A less likely, but also possible, route is through contaminated fish, fishing gear, boats or other damp equipment.”

Cefas’ Dr Paul Stebbing, a crayfish specialist, said: “This particular outbreak is a mixed blessing: an invasive non-native species will now be removed, but a highly contagious disease may spread and infect native crayfish populations in nearby rivers.”

Crayfish plague poses no risk to humans, however it is easily transferred between waters and does affect native crayfish species. Anyone who has been working on, angling in or otherwise in contact with the River Waveney in the affected area during the outbreak should take precautions to ensure that all equipment that has been in contact with water is suitably cleaned and disinfected. For more about this see www.efishbusiness.co.uk/ .

Notes to editors

1. Cefas is an internationally renowned scientific research and advisory establishment, based at Lowestoft since 1902. It also has laboratories at Burnham-on-Crouch and Weymouth, and a number of other facilities around the UK. It is an executive agency of the Department for Environment, Food and Rural Affairs (Defra).
2. Cefas undertakes work on fisheries management, environment and biodiversity protection and aquaculture. For more detail about its range of activities visit www.cefas.co.uk.
3. Cefas is the OIE (world organisation for animal health) reference laboratory for crayfish plague, and Dr Birgit Oidtmann as the named expert.
4. This is the first confirmed case of crayfish plague in the UK for almost two years. Cefas confirmed crayfish plague was the cause of a mass mortality of the white-clawed crayfish in the River Dove back in August 2005. Previously that river was a Special Area of Conservation (SAC) for the white-clawed crayfish.
5. The UK is one of the last remaining strongholds of the white-clawed crayfish in Europe, and the species is the only native UK crayfish. As such it is considered to be of great environmental importance. This species has come under significant pressure over recent decades from pollution, habitat degradation and non-native species of crayfish.
6. To help prevent the spread of crayfish plague, Cefas advise that precautions are taken when undertaking activities on waters containing North American crayfish. Moving between watercourses – to those that might contain native crayfish species – is particularly hazardous. For advice telephone the Fish Health Inspectorate on 01305 206673 or email them at fish.health.inspectorate@cefas.co.uk. Or contact the Environment Agency on 0870 850 6506.
7. The Fish Health Inspectorate (FHI), based at Cefas’ Weymouth laboratory, is dedicated to maintaining and improving fish and shellfish health in England and Wales. Its primary role is to act for Defra and the National Assembly for Wales, Agriculture Department (NAWAD) in undertaking statutory and inspection duties resulting from the EU Fish Health regime and other national legislation in the area of fish and shellfish health.
8. The Inspectorate is responsible for health certification of fish and shellfish movements from other countries, and runs an enforcement programme aimed at preventing the illegal importation of these animals. It also has responsibility for licensing of non-native crayfish and the enforcement of that keeping legislation. For more about movement controls and enforcement visit http://www.cefas.co.uk/fish-health-inspectorate/movements-imports-and-exports.aspx.
9. A photograph of a Turkish crayfish is included with this release.

Press contact:
Anne McClarnon: Telephone: 01502 524370 / Email: anne.mcclarnon@cefas.co.uk