Prolific throughout Yellowstone National Park, approximately 5,000 bison meander throughout the expansive landscape of the park year around. Yellowstone is the only place in the United States where bison have lived continuously since prehistoric times. In the 1800s, market hunting, sport hunting and the U.S. Army nearly caused the extinction of the bison, and by 1902 poachers reduced Yellowstone’s small herd to about two dozen animals. Bison are true survivors, fending off attacks by predators and the bitter cold Yellowstone winters.