Life Span of a Black-Footed Ferret

The black-footed ferret, Mustela nigripes, a member of the weasel family, is the only ferret native to North America. Identified by black legs and feet, the ferret is prevalent throughout North America, generally located in short grasslands. With a long, trim body, the ferret grows to about 24 inches long and weighs up to 4 lbs. Considered critically endangered, the black-footed ferret is a continual subject of breeding programs in which scientists gained valuable knowledge about the life cycle of the species.

  1. Gestation and Infancy

    • The gestation period for black-footed ferrets lasts about 45 days, and a litter generally produces three to five young. Kits are born blind and with soft white fur. From birth to 2 months old, the kits stay below ground to nurse and develop their eyesight and distinctive markings. After two months of age, kits leave the burrow with their mother to learn how to hunt. It also is at this age that the female moves the kits into a separate burrow from herself.

    Adulthood

    • At about 5 to 6 months of age, the kits become independent and leave both their mother and siblings. As an adult, the black-footed ferret lives mostly alone, only joining with others for mating purposes. A nocturnal carnivore, the black-footed ferret depends on prairie dogs, both as their chief food source and for shelter, as most live in abandoned prairie dog burrows. Other prey species for the black-footed ferret include squirrels, mice and even some birds.

    Mating

    • Black-footed ferrets reach sexual maturity at about 1 year of age and mate between February and April. Males do not stay with females or their young and can mate with several different females in one mating season. Females generally confine themselves to one territory, and guard it against other females. They mark rocks and vegetation with musk generated in glands below the tail. These musk secretions become stronger during the mating season.

    Life Span and Mortality

    • The life span of a black-footed ferret ranges from three to four years in the wild, while the figure is double that in captivity. Black-footed ferret mortality often coincides with that of the prairie dog. Diseases, such as distemper and pneumonia, in prairie dog communities affect the ferrets in two ways. First, these diseases decimate the dogs, limiting or depleting the ferret's available food sources. Secondly, the diseases pass from prey to predator, causing sickness in the ferret population itself.