American Bison
Bison bison

f6.7 @ 1/125S, ISO:1250, Nikon D3S w 500mm and 1.7X tele-extender

"American Bison," Wikipedia, the free encyclopedia.A bison has a shaggy, long, dark brown winter coat, and a lighter weight, lighter brown summer coat. As is typical in ungulates, the male bison are slightly larger than the female and, in some cases, can be considerably heavier. Plains bison are often in the smaller range of sizes, and Wood bison in the larger range. Head-and-body length ranges from 2 to 3.5 m (6.6 to 11.5 ft) long, the tail adding 30 to 91 cm (12 to 36 in). Shoulder height in the species can range from 152 to 186 cm (60 to 73 in). Typical weight can range from 318 to 1,000 kg (701 to 2,205 lb).
Lamar Valley, Yellowstone National Park, Wyoming