North American River Otter
Lontra canadensis

CLASS: Mammalia
ORDER: Carnivora
FAMILY: Mustelidae

Length 35 - 55 inches, weight 10 - 30 lbs.

Canada and United States, including Alaska

Lakes, streams and marshy areas. Found in and near fresh water.

Wild - Carnivore; fish, crawfish, frogs, salamanders, clams, turtles, birds, and some small mammals

Zoo - Prepared zoo diet for carnivores; fish


  • Body shape -- is elongated and streamlined for easier movement in the water enabling swimming speed up to 6 or 7 mph which is faster than most fish. Tails used as rudders.
  • Fur -- dense waterproof fur protects the otter's skin from getting wet and losing body heat. Dense, oily underfur is set off by glossy guard hairs producing a marketable coat for fur industry.
  • Insulation -- in addition to fur, a thick layer of fats lies under the skin to insulate the otter from extreme temperatures of hot and cold.
  • Nose and ears -- these are located high on the animal's head. In this way, an otter may swim partially submerged near the surface, lessening detectability by predators and intended prey. Nose and ears close like valves when the otter is submerged to prevent water entry.
  • Toes -- partially webbed to assist in swimming.
  • Binocular vision -- being a predator, otters have binocular vision enabling them to judge distance for capturing prey.
  • Time limits under water -- when needed, during hunting or to escape predators, otters may remain submerged for 3 to 4 minutes.
  • Otters are sociable and playful animals.

1 - 5 are born in April or May. Total pregnancy varies from 245 - 380 days although actual embryonic development is about 2 months. Young seperate from mom at 1 year.

CITES App. II; not endangered, but has become rare in parts of U.S. due to habitat destruction, water pollution, misuse of pesticides, excessive fur trapping, and persecution as supposed predators of game and commercial fish.

"Otters, A Study of the Recent Lutrenae", C.J. Harris
"The World of Mammals", John Ed Honders
"Mammals of the World", Walker