coypu

South American water rodent Myocastor coypus, about 60 cm/2 ft long and weighing up to 9 kg/20 lb. It has a scaly, ratlike tail, webbed hind feet, a blunt-muzzled head, and large orange incisors. The fur ‘nutria’ is reddish brown. It feeds on vegetation, and lives in burrows in rivers and lake banks.

Taken to Europe and then to North America to be farmed for their fur, many escaped or were released. In Britain, coypus escaped from fur farms and became established on the Norfolk Broads where their adult numbers reached 5,000. They destroyed crops and local vegetation, and undermined banks and dykes. After a ten-year campaign they were eradicated in 1989 at a cost of over £2 million. In 1993 escaped coypu in Louisiana, USA, were causing serious damage to coastal marshland.