Habitat: Lakes, swamps, marshes

Diet: Primarily fish, but they also take crabs, crayfish, young waterfowl, snakes, frogs, and even muskrats.

Reproduction: Males and females do not associate except during the mating season. Males often breed with several females, most commonly those whose home ranges overlap with their own. Males and females come together to breed in late winter or early spring. Births occur from November to May, with a peak in March and April. Females give birth to from 1 to 6 young per litter, with an average of 2 to 3, in a den near the water. They are born with fur, but are otherwise helpless. They open their eyes at one month of age and are weaned at about 3 months old. They begin to leave their natal range at from 6 months to a year old. Sexual maturity is reached at 2 to 3 years of age.

Behavior: Adapted to living a life in water, river otters have long, stream-lined bodies, webbed feet, and powerful legs. Their tail acts as a rudder when swimming. They have long, stiff facial whiskers that sense vibrations and have specially designed teeth to hold onto slippery fish. Since they are adapted to underwater vision, river otters are nearsighted on land.

Physical Description: These otters swim by propelling themselves with their powerful tails and flexing their long bodies. They also have webbed feet, water repellent fur to keep them dry and warm, and nostrils and ears that close in the water. Their fur is a dark brown color with a light underbelly. Their head is round with small ears and nostrils that can be shut underwater. Body length ranges from 889 to 1300 mm and tail length from 300 to 507 mm. Weight ranges from 5 to 14 kg. Males tend to be larger than the female.

Conservation Status: Threatened

Fun Facts:

	North American river otters are important predators of fish and aquatic invertebrates.
	North American river vocalize using whistles, growls, chuckles, and screams.
	They also scent mark using paired scent glands near the base of their tails or by urinating/defecating on vegetation within their home range.
	They also use touch and communicate through posture and other body signals.
	They have long and abundant whiskers are very sensitive and are used extensively in hunting, due to smell, vision, and hearing being diminished in the water.