Smithsonian National Museum of Natural History, North American Mammals
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Ondatra zibethicus

Common Muskrat

Order: Rodentia
Family: Cricetidae

Image of Ondatra zibethicus
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Conservation Status: Least Concern.

Common Muskrats, so-called for their odor, which is especially evident during the breeding season, are highly successful semi-aquatic rodents. They occur in both brackish and freshwater lakes, ponds, streams, rivers, and marshes throughout much of North America, except in parts of the South where tidal fluctuation, periodic flooding, or drought limit their distribution. Common Muskrats have a variety of aquatic adaptations, including a rudder-like tail that is flattened side-to-side, partially webbed hind feet, and fur that traps air for insulation and buoyancy. Because their fur has commercial importance, they were taken to Japan, South America, Scandinavia, and Russia, and there are now feral populations in some places where they were introduced.

Also known as:
Mudcat, Muskbeaver, Musquash, Muskrat

Range: 410-620 mm

Range: 680-1,800 g


Linnaeus, C., 1758.  Systema Naturae per regna tria naturae, secundum classis, ordines, genera, species cum characteribus, differentiis, synonymis, locis, p. 59. Tenth Edition, Vol. 1. Laurentii Salvii, Holmiae, 1:1-823.


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Ondatra zibethicus

Image of Ondatra zibethicus
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Skull of Ondatra zibethicus
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