Buffalo herd in Lamar Valley, dawn. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell8773.html Bison grazing in prairie. Theodore Roosevelt National Park, North Dakota, USA. http://www.terragalleria.com/parks/np-image.thro0603.html Bison calves. Grand Teton National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.grte8743.html Two bisons. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell1844.html Bisons in front of barn below Teton range. Grand Teton National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.grte8745.html Two buffaloes head to head. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell1836.html Bison in front of barn, with Grand Teton in the background, sunrise. Grand Teton National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.grte8744.html Bison and creek, Hayden Valley. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell8813.html Two American bisons in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49273.html Bisons and geyser cone, winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49276.html Snow-covered buffalo standing on warmer ground. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49313.html American bison in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49277.html Lone bison and thermal steam. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49317.html Skiers and bisons. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49287.html Bison crossing Firehole River in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49271.html American bison with snow sticking on face. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49318.html Bison feeding in snow-covered meadow. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49286.html Buffalo herd and Geyser Hill in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49316.html Snow-covered bison walking. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49288.html Child walking with buffaloes in the distance. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49322.html Bison herd on a warmer patch in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49314.html Close view of american buffalo in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49275.html Buffalo in creek, Hayden Valley. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell8815.html Group of buffaloes crossing river in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49272.html Bison following warm stream in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49263.html Buffalo, Hayden Valley. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell8814.html Yellowstone River, meadow, and bisons in Heyden Valley. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell0535.html Group of buffaloes. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell1835.html Bisons with thermal plume behind in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49315.html Herd of buffaloes during snow storm. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49285.html Bison moving in single file next to Firehole river, winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49256.html Firehole river and bison in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49258.html Bison and Lion Geyser in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49252.html Bisons with snowy faces. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49274.html Snow-covered bison in winter. Yellowstone National Park, Wyoming, USA. http://www.terragalleria.com/parks/np-image.yell49251.html