A clear, third eyelid, called a nictitating membrane, covers the otter's eyes when swimming underwater. This gives protection to the eye but allows the otter to see clearly. Their long, supple bodies enable them to quickly twist, turn, roll, and dive as they seem to glide effortlessly through the water. River otters can be found in a variety of freshwater habitats including streams, rivers, lakes, ponds, and marshes. They are most active at night but may be encountered at any time.
Otters feed on fish, snakes, turtles, frogs, crayfish and almost anything else they can catch.
They are sometimes blamed for decimating gamefish populations, but research shows that otters feed more on slow-moving fish species such as suckers and catfish. Otter dens are often dug into the bank of a stream or they may utilize an old beaver lodge, muskrat house, or even a hollow tree. They give birth to 2 to 4 young in early spring. Uncontrolled trapping, water pollution, and other forms of habitat destruction have contributed to this decline. In North Carolina, River Otters are still common in the eastern coastal plain, with much fewer found in the Piedmont region and almost none in the western mountains.