The birth of the litter, containing five to 10 young, occurs less than a month after mating. The young at birth are blind, hairless and almost completely helpless, but develop rapidly. They are covered with thin fur at the end of the first week, their eyes open at the end of the second week, and they normally begin leaving the lodge on short trips at about two to three weeks of age. Juveniles are essentially independent of their parents at six weeks. The muskrat plays an important role in the trapping industry and in many areas it is an important food item as well.
Minks can cause heavy mortality among juvenile muskrats.
Muskrat populations in North America are doing well in spite of heavy trapping pressure, the draining of marshes for agricultural purposes and unprecedented industrial activities. In Alaska, population numbers today are probably almost as high as they were a thousand years ago. Nan Eagleson is a wildlife biologist who lives in Denali Park and works as a naturalist guide for Denali National Park Wilderness Centers.