Yellowstone bison herd

The Yellowstone bison herd is a bison herd in Greater Yellowstone Ecosystem. It is probably the oldest and largest public bison herd in the United States, estimated in 2020 to comprise 4,800 bison. The bison are American bison of the Plains bison subspecies. Yellowstone National Park may be the only location in the United States where free-ranging bison were never extirpated, since they continued to exist in the wild and were not reintroduced.