Muskrat

The muskrat, Ondatra zibethicus, in the family Cricetidae, is a semiaquatic rodent found in fresh-water and saltwater marshes from Alaska through most of Canada and the United States. It was introduced into Europe for its fur but quickly became a pest. A dark colored polulation in Newfoundland is often classified as a separate species. O. obscurus. Muskrats are stoutly built, reaching about 33 cm (13 in) long, plus a laterally flattened 29 cm (11-in) tail, and they weigh up to 1.8 kg (4 lb). The hind feet are partly webbed. The dense, glossy coat ranges in color from grayish brown to dark brown or almost black. Muskrats live in a network of burrows in the banks of waterways or build houses of mounded vegetation in open water. They eat mainly plant material. Breeding is confined to the warmer moths in the north, where a female may have three litters a year, but occurs year round in the south. Gestation takes about 30 days, with usually three to seven young to a litter. The musk rat’s fur is of prime commercial importance.

The muskrat dives and swims in the freshwater habitat by padding with partially webbed hind feet. It builds a shelter in the water or burrows into the sides of earthen banks.