Digestion is rapid and complete with the exception of fish scales, exoskeletons of crayfish and mussels, etc. The river is a large, long mammal that is mostly dark brown and sometimes nearly black when wet. While otters live on both land and in the water, they are particularly suited for aquatic life. Their habitat is primarily wetlands, streams, rivers and ponds or lakes, sometimes bordered with timber. Their homes are burrows in banks, under roots, ledges, or trees, and in thickets of vegetation.
Otters are powerful swimmers.
They enjoy sliding down slopes and spreading out all four legs and sliding on their chest and belly into the water or a snow drift. Fish and crayfish are favored foods of otters, but they will also eat frogs, clams, snakes, turtles, muskrats, and earthworms Mating takes place in winter or early spring. The single litter is generally born the next year from January to May, and usually contains from two to four young. Adults remate immediately following birth of the young. Otter fur is one of the most beautiful and durable of American furs.