“Since the start of October, we have discovered around 150 dead animals,” National Parks Authority spokesman Hendrik Brunckhorst said on Tuesday in Husum, a coastal town in Schleswig-Holstein.
Between five and ten dead seals have been found daily on the coasts of the North Sea islands of Helgoland and Amrum since the end of last week, while up to 16 dead seals washed up every day on Sylt. Seal corpses were also found on the shores of islands Amrum and Föhr.
Many of the seals were several years old, said Brunkhorst.
Experts from Hanover’s University of Veterinary Medicine have been trying to uncover the cause of the deaths, with possible culprits including the flu and distemper - a highly contagious, viral disease that is often fatal. Results are expected within the week.
The flu was found to have killed around 200 of 1,500 dead seals found on the Danish island of Anholt since August on the Baltic Sea.
Distemper attacks the immune system. While some animals survive and develop antibodies that keep them immune from the virus for some time, bodily defenses break down steadily from year to year.
Two large-scale outbreaks of seal distemper have been recorded along the North and Baltic Sea coasts in recent decades.
Around 18,000 seals died in 1988, while around 21,700 dead seals were counted in 2002.
No signs of unusual seal deaths have been found further south in Lower Saxony, where the death toll has been “normal”, according to a spokesperson from the Office of Consumer Protection and Food Safety in Oldenburg.
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