River Otter

River Otter (Lutra canadensis)

What they look like: The River Otter is built for swimming - they have a streamlined body, short legs with webbed feet, dense fur that keeps them warm, a tapered tail, small ears, and nostrils that can close underwater. They can grow to be more than a meter long, from head to tail, and weight up to 14 kg. Males are larger in size than females (see photos).

River Otters are mammals that are relatives of the stoats, weasels, mink, badgers and wolverines. These groups of mammals are known as Mustelids. The Mustelids all have one thing in common, they all have scent glands that they use to mark off their territory.

Where they live:
River Otters are found along rivers, streams, and lakes and also in estuaries, coastal bogs, and large marine waterways such as Puget Sound and the Strait of Juan de Fuca. In the central basin, they are apparently limited to large rivers, such as the Columbia, Yakima, and Walla Walla.

Click the range map to learn more about the distribution of River Otters in Washington.

What they eat: River Otters are carnivorous (they eat meat). They eat a variety of animals, including fish, crustaceans, amphibians, snakes, water insects, snails, worms, small mammals, birds, eggs, frogs, turtles, and any aquatic invertebrates.

Behavior:

Rivers otters are mostly solitary (live alone), except for females with their young. Otters come together during the mating season in late winter or early spring.

Females give birth to 1 to 6 young per litter, with an average of 2 to 3. Otters are born with fur, but are otherwise helpless. Females give birth, nurse, and care for their young in a den near the water. The young are weaned at about 3 months old and begin to leave their mother at 6 months old. Adult females care for their juvenile offspring, who disperse by the time the otters give birth again. River otter become mature at 2 to 3 years old.

Lifespan:

In the wild River Otters live less than 10 years. In captivity they live 10 - 15 years.

Did you know?

• River otters can hold their breath for up to 8 minutes while under water.
• River otters spend two-thirds of the time on land.
• Otters always wash themselves after every meal.
• The otter is the largest member of the weasel family.
• River otters can dive to a depth of 60 feet.
• Baby otters are called pups.

River Otters

More information: Northern River Otter - Animal Diversity Web    
More photos: River Otter Photos on the Wildlife Web