Native to North America, muskrats are semi-aquatic rodents that inhabit wetlands and streams across the Continent; hunted and trapped for their dense fur and meat, they have also been introduced in Eurasia and South America. When spotted on lakes and ponds, muskrats are often mistaken for beaver; however, they are significantly smaller (weighing 5 pounds or less) and are easily identified by their long, narrow tail.
Muskrats dig dens in the banks of streams, canals and lakes or construct mounds of aquatic vegetation and mud; in either case, multiple entrances to the lodge chamber, both above and below the water line, permit escape routes from predators and access to aquatic food when the surface water is frozen. Primarily nocturnal and active throughout the year, muskrats feed on a wide variety of plant material and also consume amphibians, snails, turles and fish; they, themselves, are potential prey for coyotes, fox, otters, mink, raccoons, snapping turtles, snakes, eagles, herons and owls.
Breeding from late winter through late summer, muskrats are both polygamous and highly territorial. Females may produce up to five litters each year, with 6-10 kits per litter; as with cottontails, the young mature rapidly and females born in spring may breed by late summer. On the other hand, female muskrats chase off their youngsters when a new litter is about to arrive and often kill those that refuse to leave. Though muskrats may damage levees and dikes, especially during periods of overpopulation, their activity opens up dense cattail marshes for waterfowl and their abandoned dens provide homes for raccoons, mink and aquatic snakes; as avid birders know, Canada geese often nest atop muskrat lodges.