Dutch water boards, the organizations responsible for the country’s dikes and canals, are fighting off invaders from Germany and North America that are undermining their efforts to keep the dry parts of the country dry.
In their 2024 report, the 21 water boards, which have also been fighting dike damage by native beaver, said they are also having problems with muskrats and nutria, also known as coypu, who have crossed the border mainly from Germany and begun to tunnel into dikes and other coastal defenses, causing flooding and potentially larger damage. They also cause problems by eating reeds and bulrushes that are the food for native bird species.
In 2024, the combined 21 water boards caught a total of 65,811 muskrats, some 15,000, or 29%, more than in 2023 while 1,862 copyu were trapped and killed, 13% up from 2023. Long periods of high water levels in Germany deprived the animals of their burrows prompting them to find shelter further downstream in the Netherlands. Most were caught in the border area with Germany.
The other big invasive species issue is North American crayfish, which appear to have hitchhiked to Europe in ship ballast several years ago, and now number in the billions.
Image: Coypu, a rodent with a beaver-like tail
