Long and sleek
North American river otters are not to be mistaken for sea otters, which (among other differences) live exclusively in the ocean. Nor should they be mistaken for beavers. You can tell a river otter by its long, sleek body, webbed and clawed feet, and a long muscular tail that is slightly flattened and tapers toward the end. They are long like their weasel cousins, and have an adorably large black nose.