The rivers and streams of North America provide habitat for many different types of animals. Certain mammals lead an aquatic life, using rivers and streams to find food. They move from place to place and build their homes in or near the water. Certain reptiles spend the vast majority of their time in the water, as well, with rivers and streams among the places they frequent.
The muskrat is an adept swimmer that is found from coast to coast in the United States and throughout almost all of Canada and Alaska. The muskrat will employ a river or a stream as its home if the water is somewhat lethargic in its flow and marshy areas exist along the banks to supply food. The muskrat has hind feet that are slightly webbed and uses its tail as a rudder to steer as it swims. The muskrat can chew underwater, according to the "National Audubon Society Field Guide to Mammals," and it can remain submerged for minutes at a time. The muskrat will avoid fast currents and stay away from rocky stretches in a river or stream. The animal seeks aquatic plants such as cattails, bulrushes, ferns, water lilies and arrowhead, sometimes eating all the plant life in an area and then having to move to find ample food. In a river or stream setting, muskrats make their homes by digging elaborate dens into the banks.
The hellbender is a giant salamander that lives a totally aquatic life in fast, cold streams and rivers. It can be found from New York to Georgia, Alabama and Mississippi. The hellbender can live over two decades; its presence in a river or stream is an indicator of high water quality. Hellbenders may reach lengths in excess of two feet, possess a flat head and jaws full of teeth, although the creature is shy and harmless unless provoked. Hellbenders have a diet of crayfish, worms and snails, relying on their acute sense of smell and touch to locate food in the water. Hellbenders are the focus of many myths, with one being that they drive game fish species from the rivers and streams they frequent.
The river cooter is a freshwater turtle found in rivers and streams, living in the water and basking on rocks and logs when the opportunity arises. The river cooter grows to lengths of 12 to 16 inches, with females slightly larger than the males. The river cooter's range in the United States extends through most of the Deep South well into states like Texas and Oklahoma. River cooters are strong enough swimmers that they can live in waterways that feature quick currents. This species will bask with other turtles, like the painted turtle and the red-eared slider, often with one stacked upon another when space on a log gets tight. Those that live where the weather is cool in winter go into a dormant phase, burying into soft mud at the bottom. The diet of a river cooter includes plants and animals, with small fish, snails and insects on their menu. The "National Audubon Society Field Guide to Reptiles and Amphibians" notes that river cooters can live to be 40 years old.