The bison (Bison bison) is the largest land mammal in North America. In a typical year, more than 3,000 bison roam the grasslands of Yellowstone National Park. Bulls are more massive in appearance than cows, and more bearded. For their size, bison are agile and quick, capable of speeds in excess of 30 mph.
At one time, bison were widespread from Alaska to northern Mexico (Meagher, 1986). Wholesale slaughter of bison herds caused the extermination of wild bison from the major part of their former range until recently. Bison are now found on private and protected lands in areas of the western United States and Canada (National Bison Association, 2002). Most prominent of those herds are those of Yellowstone National Park in Wyoming and Wood Buffalo Park, Northwest Territory, Canada (Honacki, 1982).