Dens are lined with leaves, spruce or fir boughts, or pine needles. Delayed implantation keeps fertilized eggs from beginning development until around the start of denning season. Cubs are born in January or February. Litter size is usually two, but ranges from one to four cubs. Subadult females tend to stay within their mother's home range, while males usually leave their mother's range completly.
Cubs stay with their mothers for up to three years.