Myocaster coypus
Coypus, also known as river rats, are large rodents. They weigh up to 15 kg and reach 64 cm in length. The tail is round, 30–45 cm long and almost hairless. The fur is golden brown on the upper side and grey on the underside. The female has nipples towards the side of her body, so the young can be nursed while swimming.
Coypus have long whiskers on the snout and large reddish brown front teeth. They usually live in fresh water (lakes and streams) but can also survive in brackish water.
Coypus live in large family groups and are often active during the day. They dig long tunnels in embankments and may undermine dykes and dams. The entrances are above water and about 25 cm in diameter.
Coypus were introduced into Europe from South America by fur farmers at the beginning of the twentieth century. Released and escaped animals from fur farms have created well-established populations in many areas of Europe.
Coypus have five toes, with long claws on the front feet. The footprint is about 6 cm long and 6 cm wide. The hind foot has narrow webbing between the toes, and the toes are endowed with stiff hairs to aid swimming, making the prints appear wider. The tracks of the hind feet are about 12 cm long and 7 cm wide. When the animal moves on soft terrain, you can often detect the tail in the form of serpentine drag marks.
Coypu scat. L-HO.
Coypu tracks with drag marks from the tail.
The Coypu is active during the day and not particularly shy. Biopix.
Coypus feed almost exclusively on plants but may also consume insect larvae, mussels, snails, and crustaceans.
Near the burrow and feeding sites by water, the vegetation will be chewed off or heavily trampled. The animals also create visible paths between trails.
Coypu scat is 5–7 cm long, brown and sausage-shaped, and about 1 cm thick. Scat is left everywhere, both in the water and on the shore.