American Mink

The American mink, *Neogale vison*, is a semi-aquatic mustelid 46–70 cm long including a bushy tail, weighing 0.7–1.6 kg with males roughly twice the mass of females. The coat is dense, glossy, and dark chocolate to near-black with a distinctive white chin patch and irregular white throat or chest spots that are unique to each individual; oily guard hairs make the pelt effectively waterproof. Partially webbed feet and the ability to dive to 5 m and swim 30 m underwater support an aquatic hunting style. Mating runs February–April with delayed implantation, and a single litter of 3–6 kits is born in late April or May. Kits swim at 8 weeks, disperse by autumn, and wild lifespan averages 3 years.

Mink are solitary, mainly nocturnal and crepuscular, and forage along linear water corridors — streams, ditches, ponds, and shorelines — taking fish, crayfish, frogs, muskrats, waterfowl, eggs, and rodents. Like other weasels they surplus-kill when prey is concentrated, which makes ornamental koi ponds, backyard duck flocks, and small hatcheries frequent targets; a single mink can empty a pond in one night. Males range over 2–5 km of shoreline, females 1–2 km, marking with a pungent anal-gland musk. They are strong climbers and swimmers, readily crossing fences and gaining entry through drains and culverts. Escaped and feral farmed mink can persist locally and are considered invasive in many regions outside their native range.