Today, visitors to Yellowstone National Park in Wyoming and Custer State Park in South Dakota can see herds of magnificent bison still roaming free on the grasslands. The bison is a symbol of the American West, and during the 18th century, there was an estimated population of 60 million bison. But by the end of the 19th century, due to market hunting, the buffalo were nearly extinct, with less than 1000 known animals. Thirty or so of these lived in Yellowstone.