Weighing only about 0.8 ounces, baby muskrats are born blind and hairless. After about two weeks, they develop fur, begin swimming and are able to stay underwater for as long as 15 minutes. In warmer environments, muskrats mature in six months; in colder environments, maturation takes about a year.
The muskrat is a large rodent about 1-2 feet in length, with a stocky body, rounded head and a long, scaly black tail. Its fur is medium to dark brown or black in color, with the belly a shade lighter. Its tail is laterally flat and works like a rudder to help the muskrat maneuver in water. On land, its tail drags on the ground, which makes muskrat tracks easily recognizable.
Muskrats are found from northern Canada to just south of the Mexican border, with a habitat consisting of swamps, marshes, rivers, lakes, ponds, drainage ditches and canals. They prefer an environment with 4 to 6 feet of still or slow-moving water. Muskrats live in groups consisting of a male and female pair and their young. Muskrat families build nests for protection from cold weather and predators. They are most active near dawn and dusk or at night, and feed mostly on aquatic vegetation.