A bison shakes off freshly fallen snow. The extreme cold seems not to affect the bison. They are so well insulated the snow on their back often does not even melt from body heat. Yellowstone National Park, Wyoming.
Heavy snow falls near Yellowstone Lake and nearly obscures the bison as they search for what little food remains. Yellowstone National Park, Wyoming.
On an exceptionally cold day in Yellowstone National Park the pine needles of this pine tree are covered in frost and ice.
