The Mink is a large, brown, semi-aquatic weasel. Males are 20 – 24 inches long, females about one-fifth smaller. Mink are dark brown, slightly paler beneath, with the tip of the tail nearly black. Their toes are partially webbed.
Minks live statewide in Colorado but are most abundant in the mountains, near beaver ponds. The beaver pond provides still-water habitat and an abundance of food on the plains.
Minks live in burrows, dens of muskrats, or tree hollows but are only weak burrowers.
Minks primarily eat muskrats, nestling waterfowl, frogs, salamanders, fish, beaver kits and insects, crayfish may be a staple in season. Mink kill more food than they can eat at once, and excess food is stored, especially in winter.
Breeding occurs in summer, but implantation of embryos is delayed. Gestation takes five to ten weeks, with one to six (usually four) young born in April or May. Newborns are tiny but grow quite rapidly, doubling their weight five or six times to reach 40 percent of adult weight by the time they wean at seven weeks of age.