Smithsonian National Museum of Natural History, North American Mammals
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Lontra canadensis

North American River Otter

Order: Carnivora
Family: Mustelidae

Image of Lontra canadensis
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Conservation Status: Least Concern.

North American River Otter can be thought of - and in a very real sense are - semi-aquatic weasels. Like fishers, martens, and mink, they have long, slender bodies, short limbs, and a short face, plus a set of adaptations for their aquatic lifestyle: an oily, waterproof coat, webbed toes, and small external ears. North American River Otter are good swimmers and divers, able to stay underwater for up to eight minutes. They feed on crayfish, crabs, fish, birds, small mammals, and some aquatic plants. They once lived in streams, rivers, lakes, swamps, and coastal areas throughout Canada and the United States. Now they are gone from the central and eastern United States, and extinct or rare in Arizona, Colorado, Indiana, Iowa, Kansas, Kentucky, Nebraska, New Mexico, North Dakota, Ohio, Oklahoma, South Dakota, Tennessee, Utah, and West Virginia. Scientific studies have shown them to be sensitive to pollution. Still these animals are commercially harvested: 20,000 - 30,000 are taken annually for their lustrous fur.

Also known as:
River Otter, Common Otter, Northern River Otter

Sexual Dimorphism:
Males are larger than females.

Range: 889-1,300 mm

Range: 5-14 kg


Schreber, J.C.D., 1777.  in Schreber's Die Säugthiere in Abbildungen nach der Natur mit Beschreibungen, Wolfgang Walther, Erlangen, 7 volumes, 1774-1846; 3(18):pl. 126.B[1776], text: 3(26):457, 588(index)[1777].


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Lontra canadensis

Image of Lontra canadensis
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Skull of Lontra canadensis
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