Wildlife photography of a bull bison and blue hot spring in Winter with fog, snow and trees

A solitary bull Bison slowly makes his way through wintry steam around the hot springs of Norris Geyser Basin. Bison often seek out hydrothermal areas with less snow for food and warmth during the short days, deep snow, and extremely cold temperatures that are hallmarks of Winter in Yellowstone National Park. These incredibly well-adapted animals are able to lower their metabolic rate in the Winter, requiring less energy and forage, and only when temperatures reach about -40°F must their metabolism increase to maintain body temperature.