Records concentrate in the Matanuska-Susitna Valley and around Denali National Park and Preserve, with more scattered reports from Kodiak National Wildlife Refuge, Kenai Fjords National Park, and the North Slope. Alaska holds the heaviest concentration of American ermine records anywhere in the country, tracking the boreal forest, wetland margins, and subarctic tundra this small weasel favors.
Ermine here don’t dig their own dens. They take over rock piles, hollow logs, and the burrows of the voles and squirrels they hunt, then kill prey many times their own weight with a fast rush and a bite at the base of the skull. Twice a year they molt: chestnut brown with a cream throat in summer, pure white for winter, except for the last inch or two of the tail, which stays black in every season and every coat.
Records run year-round with the heaviest concentrations in deep winter and again in August. That pattern says more about a secretive, mostly solitary animal that’s easy to overlook than about any real shift in numbers through the seasons.
Full species profile
