Muskrats have thick, glossy fur that varies in color from blackish to silvery-brown. (U.S. Fish & Wildlife Service)
The muskrat is a semi-aquatic mammal with brownish fur and a long, rudder-like tail. It is found in marshes and other shallow-water areas throughout the Chesapeake Bay watershed.
Appearance:
Thick, glossy fur that varies in color from blackish to silvery-brown
Paler throat and belly
Scaly, hairless, rudder-like tail that is flattened on the sides and can grow to 10 inches long
Small ears that are nearly hidden within its fur
Partially webbed hind feet
Grows to a total length of 16-24 inches and can weigh up to 4 pounds
Habitat:
Found mostly in marshes, but also lives in other types of wetlands such as swamps and in ponds, lakes, streams and rivers
Prefers shallow areas with 4-6 feet of water
Builds a dome-shaped lodge of mud and marsh plants on top of tree stumps in shallow water. Lodges can be up to 3 feet tall and have one or more underwater entrances.
Occasionally burrows into stream banks to create a den
Mostly nocturnal, but can be seen swimming or sunning itself on a log during the day
Range:
Found throughout the Chesapeake Bay watershed
Feeding:
Feeds mostly on the roots and rhizomes of marsh plants, especially cattails and rushes
Will also eat fish, frogs, insects and shellfish
Consumes about one-third of its weight every day
Builds separate feeding lodges or platforms so it can get out of the water and eat
Predators:
Has many predators, including minks, raccoons, owls, hawks, red foxes and bald eagles
Humans hunt muskrats for meat, fur and sport
Hides from predators by diving underwater or into its lodge
Reproduction and Life Cycle:
Breeds frequently throughout most of the year
Nests in chambers inside its lodge
Females have 1-3 litters of 5-6 young (called kits) each year
Gestationperiod lasts less than one month
Young are born blind
Within 10 days young can swim and within 21 days they can eat plants
After one month, the female ejects her now-independent young from the lodge
Can live 3-4 years in the wild
Other Facts:
The most common semi-aquatic mammal found in the Bay watershed’s marshes
Named for the strong musky odor adults emit to communicate with one another
Ondatrais the Iroquois name for the muskrat and zibethicus means “musky-odored” in Latin
Poor vision, hearing and smell
Can be confused with beavers and nutria. Muskrats can be distinguished by their smaller size and their rudder-like tails that are flattened on the sides.
Has fur mouth flaps behind its teeth to prevent water from getting in its mouth while chewing underwater.
Has an extraordinary lung capacity. Muskrats have been observed swimming underwater for up to 17 minutes, surfacing for three seconds, and then going back underwater for another 10 minutes.
Snakes, turtles, Canadageese and many other animals use the tops of muskrat lodges as habitat
Sources and Additional Information:
Chesapeake Bay: Nature of the Estuary, A Field Guide by Christopher P. White
