Identification - The muskrat has a stocky appearance with small eyes and very short, rounded ears. The average weight for an adult is 1 ½ pounds. The color of its fur varies from dark tan to reddish brown to black with a gray to silver or tan belly. The muskrats "rat like" tail is scaly and flattened from side to side, which is used as a rudder when in the water.
Habitat - The habitat for muskrats is almost any place where water and food are available. This includes streams, ponds, lakes, canals, roadside ditches swamps, mine pits, and other wetland areas. In shallow waters with plentiful vegetation, they use plant materials to construct their houses, which are generally conical in shape. These houses may be six to eight feet wide and two to four feet tall. Elsewhere, they prefer bank dens. Muskrats often have feeding houses, platforms and chambers that are somewhat smaller than the houses used for dens.
Diet - Muskrats are primarily vegetarians. They will eat almost any aquatic vegetation as well as some field crops where they are grown adjacent to suitable habitat. Some of the preferred natural foods include cattail, pickerel weed, bulrush, smart weed, duck potato, horsetail, water lily, sedges, young willow regeneration, and other aquatics.
Reproduction - The muskrat's breeding period is from February-August; peak activity is in April. Gestation is 22-30 days, with the birth period being March-September; peak period is in May. They average two litters per year with an average of six young per litter.
Damage caused by muskrats is, in most cases,
primarily due to their burrowing activity. This may not be readily evident
until serious damage has occurred. Visual
inspection looking for "runs" or trails from just below the normal
water surface up to three feet deep is a good way to identify a potential
problem.
Exclusion - Fencing or rip-rap (large stones) along the banks may prevent the muskrats from leaving a pond to cut garden plants or crops.
Habitat Modification - eliminate aquatic or other suitable foods eaten by muskrats.
Repellents - No repellents are currently registered for muskrats, and none are known that are effective, practical, and environmentally safe.
Toxicants - Zinc phosphide is the only toxicant registered for muskrat control. This is a restricted use pesticide.
Fumigants - No fumigants currently are registered for muskrat control.
Traps - The two most effective and commonly used types of traps for muskrat are the Conibear type size 110 and the leghold types such as the long spring size No. 1, 1 ½ or 2.
Shooting - Shooting
may eliminate one or two individuals in a small farm pond. Concentrated
efforts will have to be made at dusk or in the early morning hours for effective
control. Check with DNR for specific regulations and permits.
Michigan State University Extension programs and materials are open to all without regard to race, color, national origin, sex, disability, age or religion. Michigan State University, U.S. Department of Agriculture and counties cooperating. MSU is an affirmative-action equal opportunity institution.
