After some poor years, salmon have returned in greater numbers to the Torne River, but many show signs of fungal infection.
Hampus Hällbom at the National Veterinary Institute says the agency is receiving many reports of dead or attacked salmon. The fungus appears as white patches on the fish, and the worst affected are sometimes described as zombie salmon.
Fungal spores are always present in the water, but salmon become ill mainly if weakened or mechanically damaged. Hällbom says the underlying cause is unknown.
Similar attacks have increased sharply over the past 10–15 years. SVA urges the public to report sick or dead salmon with photos to map the spread.
