Members of the weasel family, playful river otters enjoy sliding down muddy and snowy hills, bouncing objects on their paws, playing tag, and wrestling.
Built for swimming, river otters have a streamlined body, short legs with webbed feet, dense fur that keeps otters 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.
Once abundant in U.S. and Canadian rivers, lakes, and coastal areas, river otters have suffered from fur trapping, water pollution, habitat destruction, pesticides, and other threats. Today, they can be found in parts of Canada, the Northwest, upper Great Lakes area, New England, and Atlantic and Gulf Coast states.
River otters can make themselves at home in nearly any inland waterway, as well as estuaries and marine coves.
These otters eat fish, frogs, crayfish, mollusks, other invertebrates, and small mammals.
Male and female otters are generally solitary, except when adult females care for their juvenile offspring, who disperse by the time the otters give birth again.
The largest of the 13 species of otter is the giant otter, reaching a length of up to 1.8 m and known as the river wolf in Peru. The smallest is the Asian small-clawed otter, less than a meter long.
North American river otters can dive to a depth of 60 feet.