Wildlife

River Otter

River otters, also referred to as land otters, have a powerful, low-slung, slender body and flattened heads. They have a tapered tail, short legs, and webbed feet. Large males can grow to almost five feet long and stand 9 to 10 inches high at the shoulder. Most river otters weigh between 15 and 35 pounds with females being about a quarter smaller than males. The fur is very dense, with shades of brown that are distinctively lighter on the underparts, chin, and throat.

River otters eat mainly fish, but also consume a variety of foods including insects, frogs, birds, eggs, small mammals, vegetation, and shellfish. They are mostly aquatic but will travel great distances over land to reach other streams or lakes. River otters are also social, and tend to travel in pairs or larger groups.

Breeding usually occurs May to July with young born in April or May. Litters average two pups but can range from one to five.

Sea Otter

Sea otters have broad heads with small ears, their tails arelong and flat, and they have webbed feet. Adult males average 80 pounds and can reach up to five feet long. Females average four feet long and 60 pounds. Sea otters usually appear brown but their underfur ranges from brown, to nearly black, and older animals develop an almost gray head. Sea otters have the densest fur of any mammal. They can be distinguished from river otters by their larger size, flatter tail and grayish head.

Sea otters prey mostly upon clams, mussels, snails, crabs, and slow moving fish in some areas. They are a marine mammal and are usually found foraging near shore. Sea otters are one of the few mammals observed to use tools using rocks to break the shells of shellfish and mollusks.

Breeding and pupping occur year-round, and there is usually one pup born every one or two years.

The U.S. Fish and Wildlife Service has management authority for three species of marine mammals in Alaska: sea otters, Pacific walrus, and polar bears. The Marine Mammal Protection Act of 1972 gave the U.S. Fish and Wildlife Service this management responsibility. The Marine Mammal Protection Act now prohibits a commercial harvest of sea otters and allows only coastal Alaska Natives to hunt sea otters for subsistence and the creation of handicrafts. Sea otters do not regularly occur on the Togiak National Wildlife Refuge, however, there has been at least one sighting of a live sea otter recorded. The USFWS Marine Mammals Management Office currently manages sea otters in Alaska.

Resources:

Burt, William H. and Richard P. Grossenheider. 1980. Peterson field guide to mammals. Houghton Mifflin Company. Boston Massachusetts.

Alaska Geographic Society. 1996. Mammals of Alaska: a comprehensive field guide from the publishers of Alaska geographic. The Alaska Geographic Society. Anchorage Alaska.

For more information, visit the Alaska Department of Fish and Game's wildlife notebook river otter and sea otter pages.

Last updated: July 24, 2008