Ondatra zibethicus
Order: Rodentia
Family: Cricetidae
Status: Very abundant. One of the most important fur animals in
North America. Can cause damage to dikes by burrowing. Very valuable
fur animal. Official Montana furbearer managed and protected by regulated
fur harvest seasons.
Identifying Characteristics: Muskrats are large voles adapted to
aquatic conditions. The name muskrat is related to odoriferous
secretions from the perineal glands. The long naked tail flattened
laterally distinguishes muskrats from other mammals. Webbed hind
feet. Fur is dense and rich brown and a coarse guard hair overlay and
thick waterproof underlayer. Color varies from dark brown to black.
Total length: 16 to 26 inches. Weight: 2 to 4 pounds.
Habitat: The most widespread of North American microtine (a subfamily
of mice) rodents. Marshes, edges of ponds, lakes, streams, cattails, and
rushes are typical habitats. An essential habitat ingredient is water of
sufficient depth or velocity to prevent freezing. The presence of
herbaceous vegetation, both aquatic and terrestrial, is another essential
ingredient. In general, has very flexible habitat requirements and often
coexists in habitats used by beavers.
Food Habits: Primarily herbivorous and will eat virtually any
vegetable matter. Utilizes shoots, roots, bulbs, and leaves of aquatic
plants. Cattails and bulrush are preferred foods. Will also consume
cultivated crops. On occasion will eat animal matter. Food is stored
in the burrow or den and during winter may even eat part of its own lodge.
Life History: May be thought of as an overgrown subaquatic vole.
Mostly active at night but daytime activity is not unusual. Often builds
conspicuous dome-shaped houses. Breeds during spring and summer. 5
or 6 young are born after a 22 to 30 gestation. May have two or three
litters per year.
Similar Species: Beaver - has large dorsally flattened scale over
tail.
Further Information
