Wildlife photography of a bull bison enduring blizzard conditions in Yellowstone National Park

Through blowing snow and bitter wind, a bull bison stoically endures blizzard conditions on a cruel Winter morning in Yellowstone National Park. Winter in Yellowstone is Extreme to say the least, with recorded temperatures below -65°F and average snowfalls greater than 600 inches. Because food is so scarce, energy must be conserved, and bison have adapted by lowering their metabolic rate to require less energy and forage. Combined with the bison’s dense fur for exceptional insulation, the animals are incredibly tolerant to cold. In fact -40°F is the bison’s lower critical temperature at which it must increase its metabolism to maintain body temperature.