Dean M. Chriss
Bison Herd in Fog, Yellowstone National Park

Bison Herd in Fog

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Bison are the largest land animal in North America. Sixty million of them once roamed our grasslands in herds that could measure 50 miles across. Their range extended east to the Atlantic Seaboard of the United States, south to Florida and the Mexican states of Durango and Nuevo León, and to Great Bear Lake in far northwestern Canada. By 1884 bison were nearly extinct, with only about 325 wild bison remaining in the United States. This was due to a combination of commercial hunting and slaughter in the 19th century and introduction of bovine diseases from domestic cattle. The United States Army was ordered to protect the remaining herd in Yellowstone National Park where only 25 remained. Today Yellowstone is home to the last truly wild and free-roaming population of bison in the United States, which numbers about 16,000.