Wildlife

Crayfish Plague and Native Species Welfare in UK Rivers

Crayfish plague carried by invasive signal crayfish has devastated native white-clawed crayfish populations, causing widespread population welfare collapse.

Key Facts

Native white-clawed crayfish listed as Endangered on IUCN Red List
Signal crayfish introduced from North America carries plague without symptoms
Crayfish plague fungus Aphanomyces astaci causes 100 percent mortality in native species
Ark sites in isolated water bodies protect disease-free populations
White-clawed crayfish can live up to 12 years in optimal conditions

Welfare Considerations

Crayfish plague causes acute physiological deterioration and mass mortality in affected native populations. The welfare impact across entire river catchments is catastrophic and usually irreversible once infection is established. Surviving individuals in isolated ark sites represent the only hope for genetic preservation.

What You Can Do

Never move water or equipment between river catchments
Report signal crayfish to the Environment Agency
Support white-clawed crayfish ark site creation and management
Donate to conservation breeding programmes for native crayfish