The bison is a member of the bovine family. Commonly called "buffalo" (which is actually a different species not found in North America), it is the largest land mammal in North America. There are two subspecies: the wood bison in northern Canada and the plains bison which once roamed across much of the continent. The bison has a large head with relatively small, curving horns. Its dark brown coat is long and shaggy on the forequarters, including the front legs, neck, and shoulders, while the rest of the body has shorter, finer hair.

Bison are considered a keystone species -  they once roamed the continent in great herds, and their grazing pressure helped shape the ecology of the Great Plains.

Historically, bison numbered an estimated 20-30 million. Unregulated shooting of bison, which culminated in mass slaughters during the 1870s, reduced the population to 1,091 in 1889. Today, approximately 500,000 bison live across North America. Most are not pure bison but rather have been cross-bred with cattle in the past and are raised as livestock on ranches.

Fewer than 30,000 bison are in conservation herds, and fewer than 5,000 are free-ranging and disease-free.

How You Can Help bison and other wildlife by adopting a bison at our Wildlife Adoption Center.

Take Action for Wildlife at our Wildlife Action Center.

For additional information:

Visit Defenders' Imperiled Species: Bison pages for more information about what Defenders is doing to help.