Muskrats have a high reproductive rate, producing up to four litters per year each with six to seven young. They are polygamous and breeding takes place from late March through July. After a gestation period of 28 to 30 days, the young are born blind, helpless, and almost naked. In two weeks, their eyes open and in approximately eight weeks they are weaned from their mother. Muskrat populations appear to be cyclical in nature and influenced by the availability of food.
Muskrats eat a variety of food, though, and usually are able to maintain high population levels.
They have a high reproductive potential and have always been widely distributed and abundant in Connecticut. Native Americans and early settlers utilized muskrats as a source of food and fur but had little influence on population levels. They make their homes in bank dens or lodges similar to those of the beaver but smaller in size. Muskrats excavate dens by burrowing into the banks of slow-moving streams with their sharp front claws. The dens are complete with dry chambers and underwater tunnels, and there are ventilation holes which are hidden at the surface by shrubs, branches, and thick vegetation.