Bison are large, even-toed hoofed mammals of the family Bovidae. Two subspecies of bison exist in North America: the plains bison (Bison bison bison) and the wood bison (Bison bison athabascae). Historically, the plains bison lived primarily in the Great Plains of central North America, while the wood bison lived further north, from Alaska into the Yukon and the Northwest Territories, and in the northern portions of British Columbia, Alberta and Saskatchewan. Prior to the arrival of Europeans, it’s estimated that plains bison numbered 30 million and wood bison 170,000. Various aspects of European colonization led to the rapid depopulation of North America’s bison. By the late 1800s, plains bison no longer existed in Canada, and wood bison numbered about 200. Conservation efforts in both Canada and the United States mean that today, North America’s plains bison population fluctuates between 350,000 and 400,000, and wood bison between 5,000 and 7,000.