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Enhydra lutris

Sea Otter

Order: Carnivora
Family: Mustelidae

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Image of Enhydra lutris
Enhydra lutris - female and juvenile above, male below
Click to enlarge. (106 kb)

Conservation Status: Endangered.

The Sea Otter is the largest member of family Mustelidae, and the smallest marine mammal. Sea Otters are more aquatic even than seals and sea lions, because they mate and give birth in the water. They are tool users, using rocks to pound open hard-shelled prey, such as abalone. Once hunted almost to extinction for their fur, but now protected, they have made a comeback. This has stirred controversy where their predation on abalone, crabs, clams, and sea urchins affects shellfisheries. Ecologists are beginning to understand the larger, long-term role they play in shaping the marine environment, by eating creatures such as sea urchins. Sea urchins feed onand if unchecked, can destroykelp. Vast underwater kelp forests are at the base of the coastal food web and also provide shelter for countless organisms.

Range: 1,260-1,450 mm males; 1,070-1,400 mm females

Range: 18-45 kg males; 11-33 kg females


Linnaeus, C., 1758.  Systema Naturae per regna tria naturae, secundum classis, ordines, genera, species cum characteribus, differentiis, synonymis, locis, Tenth Edition, Laurentii Salvii, Stockholm, 1:45, 824 pp.


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Enhydra lutris

Image of Enhydra lutris
Click to enlarge. (124kb)

Image of Enhydra lutris
Click to enlarge. (82kb)

Skull of Enhydra lutris
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Bones and Teeth

Enhydra lutris
First and second left lower molars (right to left). Click to enlarge. (17kb)

Enhydra lutris
Last upper premolar and first upper right molar (right to left). Click to enlarge. (22kb)