The coypu or nutria (Myocastor coypus) is a large, crepuscular, semi-aquatic rodent native to South America, but now also present in Europe, Asia, and North America. In most regions, the coypu is considered a pest. However, in Eastern Europe and Central Asia, it is still valued for its fur.
The coypu somewhat resembles a very large rat in appearance. Adults are typically 5-9 kg (10-20 lbs) in weight, and 40-60 cm (15-24 in) in body length, with a 30-45 cm (12-18 in) tail. They can also be identified by their bright orange-yellow incisor teeth (unlike rats, which have brownish yellow incisors).
Coypu can also be mistaken for another widely dispersed semi-aquatic rodent that occupies the same wetland habitats, the muskrat. However, the muskrat is smaller, more tolerant of cold climates, and has a dorso/ventrally flattened tail that it uses to assist in swimming, whereas the tail of a coypu is round.
They were imported to many parts of the world due to their once highly desired fur. As demand for coypu fur declined, they have since become pests in many areas, destroying aquatic vegetation, irrigation systems, eroding river banks and displacing native animals. For example, coypu were introduced to Louisiana in the 1930s for its fur, and the damage the copyu have caused is so severe that in 2005 a bounty program was placed in effect to aid in controlling the animal.
In addition to direct environmental damage, coypu are the host for a nematode parasite (Strongyloides myopotami) that can infect the skin of humans. When this happens the condition is called "nutria itch".
The coypu or nutria (Myocastor coypus) is a large, crepuscular, semi-aquatic rodent native to South America, but now also present in Europe, Asia, and North America. In most regions, the coypu is considered a pest. However, in Eastern Europe and Central Asia, it is still valued for its fur.
