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Northern Sea Otter

The northern sea otter (enhydra lutris kenyoni) is a highly active marine mammal. They are the heaviest members of the weasel family, but among the smallest marine mammals.

Size: Full grown males weigh up to 100 pounds and are five-feet tall, while females are smaller weighing about 85 pounds and growing to about four-feet tall

Life Span: Northern sea otters in the wild live to between 15 and 20 years. In Zoos, they can live up to 20 years or longer.

Color: Northern sea otter fur is brown or a reddish brown

Continent: North America

Range: Alaska to Washington State

Habitat: Sea otters live in coastal waters 50 to 75 feet deep, and usually stay within a couple feet of the shore. They are found most often in areas with protection from the most severe ocean winds, such as rocky coastlines, thick kelp forests, and barrier reefs.

Food: Northern sea otters eat mussels, clams, crabs, sea urchins, and fish. Sea otters are one of only a few mammals who use tools when eating. Sea otters will dive for their food and always return with a rock. They roll on to their backs, set the food on their chest, and then use the rock to break open the hard shells.

Reproduction: Northern sea otters mate year-round. Males will reproduce with multiple females. Males will "show off" to attract the female's attention. Males will do corkscrews in the water and swim around the female quickly, turning around and over. Mating occurs for several days. Gestation is usually seven to eight months. Only one baby, called a pup, is born at a time. Pups weigh between two and three pounds at birth, and have a yellowish-brown fur color. The baby fur lasts about three to four months before turning darker brown. Pups rely on their mothers until about 15 months of age and learn how to forage for food on their own.

Fun Facts: Sea otter fur has between 800,000 to one million hairs per square inch. They have the thickest fur of any mammal. They can eat up to one-third of their body weight in sea food every day.