Denali in Winter
The apparent dearth of winter wildlife in Denali is deceiving. Many animals remain, eking out a living through special adaptations to the cold and snow. Close inspection reveals an abundance of animal tracks: ptarmigan, ravens, moose, caribou, wolverines, foxes, snowshoe hares, wolves, lynx, and many smaller mammals all leave their signs in the snow. Voles, lemmings, and shrews remain active in a world of tunnels and chambers hidden beneath the snow, while ptarmigan, snowshoe hares, and weasels seasonally camouflage themselves in white to escape detection.
Another species that blends well with winter's white is the Dall sheep. Like many northern animals, the sheep's coat thickens in winter. Two to three inches deep, with coarse, hollow hairs that help to trap warmth, the fur is ideally suited for extreme cold and high winds. This enables sheep to survive on the high, windswept ridges where grasses and other low-growing tundra plants stay exposed. Heavy snowfalls that bury these plants can take a heavy toll on the sheep population: Hundreds of sheep died in the winter of 1931-1932, when 77 inches of snow fell in just six days.
Remarkably, Dall sheep wait until November and December to mate, an odd time, since they are being tested by such severe weather then. Competition among males leads to spectacularly violent head-butting battles, which lucky explorers might witness. Rams will repeatedly charge each other on their hind legs, dropping to all fours in time for a head-cracking butt.
Besides camouflage, thick coats, and hibernation, Denali's wildlife has adapted to winter in numerous ways. The long back feet of the snowshoe hare do indeed work like snowshoes, spreading the animal's weight and increasing its mobility on snow. Lynx, which dine almost exclusively on hares in winter, have a similar adaptation. Their outsized feet (four inches long by three and a half to four inches wide) and lightweight bodies help these northern cats from sinking deeply in snow, and their long legs give them extra power when chasing prey through the snowpack. The large hooves of caribou also act something like snowshoes and are used as shovels when digging through the snowpack for food. Wolves, which often disperse in summer, when there's a greater abundance of food, form packs in winter, a hunting strategy that increases their odds of taking down large prey such as moose and caribou.
Details mentioned in this article were accurate at the time of publication