American Bison

ORDER: Artiodactyla

FAMILY: Bovidae

GENUS: Bison

SPECIES: bison bison

Massive head and forequarters covered with long, dark brown woolly hair. Short broad forehead, short neck, and high humped shoulders, with tufted tail. Long hairs of chin form long beard. Hips and hindquarters are much smaller and without long hair thus forming a distinct slope from hump to tail. Some stand six feet at the shoulder and weigh as much as a ton. Have short, sharp, up-curved horns. Shaggy winter coat falls off in patches in spring; color is dark brown in winter, lighter in summer.

Open plains of U.S. and Canada originally. Now found only in parks and reserves.

Herbivorous. Majority of the diet is composed of grasses.

Graze mostly in the morning and evening. Grooming is an important daily activity. Scrub heads, necks, and sides on trees, branches and tree trunks. Like to wallow in dust or mud. Grunt while on the move; make roaring sound when mating. Curiosity highly developed. Highly developed sense of smell. Good hearing. Will charge when cornered. Bulls can run up to 30 m.p.h. Herd size varies from a family unit to thousands for migration; cow is leader. Fights for rank in the herd often end with serious injuries or death. Mate in August and September. Gestation period is 270-285 days. Single reddish-colored calf is born in May or June. Females calve alone; rejoin herd when calf can stand after 3 or 4 days. Develops characteristic hump at two months. Nurses for one year; mature at three years. Lifespan is 18-22 years.

They eat snow when water is covered with ice.

Bison came to North America during the Pleistocene Epoch via the Bering land bridge. Eventually they ranged from Canada's Great Slave Lake to Mexico and from eastern Oregon almost to the Atlantic. They especially thrived on the Great Plains where some 30 million formed the biggest mass of large mammals ever to tread the globe. Early French settlers who saw herds living near the East Coast called them bison because they looked like a European cousin. A later English naturalist described them as buffalo which stuck, even though the term is more correctly applied to other types of wild oxen found in Asia and Africa. Bison are susceptible to tuberculosis, anthrax, and brucellosis. Since these diseases theoretically can be transmitted to domestic livestock, ranchers (near Yellowstone Park for instance) become upset when bison wander onto private land.

The bison are located in the High Veldt and can be seen from the Sky Ride.

Two subspecies of American bison are recognized: plains bison and wood bison of Canada. Their number was reduced to 750 in 1890. They were then protected and now number about 80,000. Bison live only in parks and reserves. Listed as Near Threatened by IUCN.


  1. MacDonald, David. 1984. Encyclopedia of Mammals. Equinox, Ltd, Oxford.
  2. Nowak, Ronald. 1991. Walker
  3. Turbak, Gary. 1986. "When the Buffalo Roam", National Wildlife, June-July, pp. 30-35.