A Message from the Environment Agency

Warning to all River Wensum users

Crayfish plague outbreak confirmed

What are we telling you about?

Thousands of native White Clawed Crayfish have died on the River Wensum near Fakenham, Norfolk. Results from specimens sent away for analysis confirm that crayfish plague was the cause.

Where is the impact?

The River Wensum near Fakenham, Norfolk.

What you can do to help?

We are strongly advising anyone using equipment in the river takes the recommended precautions before using the same equipment in any other river system. Anything that comes into contact with the water – keep nets, waders or wellies, canoes or other craft, and farm machinery could potentially spread the disease. To stop this happening, please follow these steps: Clean off any mud or vegetation and remove any standing water  then either thoroughly dry the equipment, preferably in sunlight making sure all nooks and crannies are dry. Or treat with a disinfectant capable of killing fungal spores.

What is crayfish plague?

Crayfish plague is a non-native water mould (fungus) that is carried by American signal crayfish. Spores of crayfish plague can be carried elsewhere and to other watercourses if equipment that has been in the water has not been thoroughly cleaned. This virulent disease has wiped out many populations of our native white-clawed crayfish in England and Wales. Although signal crayfish carry the disease they are not susceptible to it. It is spread by affected crayfish or, more commonly, equipment such as fishing nets, boats etc being transferred from infected waters. This disease is has already wiped out many native populations across the country leaving remaining natives increasingly vulnerable. They were once widespread and the only true native species of crayfish to England and   Wales but the introduction of American signal crayfish in the 1970s has put them under increasing pressure.

Contacting us

If you have any questions about the information on this sheet please contact:

Helen Beardsley

01473 706500


Or Amy Prendergast

01473 706502


To report sightings of dead aquatic life please contact our incident hotline on 0800 80 70 60.

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