Bighorn Sheep ram paused in the light snowfall - Lamar Valley, Yellowstone National Park
A pregnant pronghorn - Yellowstone National Park
Mountain Goat on colorful, precipitous terrain - Yellowstone National Park
American Bison plowing through the deep snow to forage for buried food. - Yellowstone National Park, Wyoming
Bighorn Sheep Ram - Yellowstone National Park
Adult bison showing the ropes with a young bison - Crane Trust, Kearney, Nebraska
Pronghorn Antelope Doe - near Mammoth Hot Springs, Yellowstone National Park, Wyoming
Pair of Bighorn Sheep rams on snow-topped hill - Yellowstone National Park, Wyoming
Herd of bison in the midst of snowfall - Lamar Valley, Yellowstone National Park, Wyoming
Pronghorn Antelope
Bighorn sheep ram - Grand Teton National Park
Bison Herd against the Teton Range backdrop - Grand Teton National Park, Wyoming
Head Banging
A couple of rams head-butt for dominance. - Grand Teton National Park
Bighorn Sheep - Grand Teton National Park
Bison Family
Springtime is family time! Bull, calf and cow passes by cautiously. - Yellowstone National Park
Bighorn Sheep - Badlands National Park
A lone bison in the midst of wintry season - Yellowstone National Park
Head butting Big Horn Sheep - Grand Teton National Park, Wyoming
