Buffalo once roamed the Interior Plains in large numbers.

Specifically, the American bison, commonly referred to as buffalo, were a defining species of the region. These massive animals played a crucial role in the ecosystem, influencing the grassland habitat and serving as a primary food source for many Native American tribes. In the 19th century, their populations drastically declined due to overhunting and habitat loss, but conservation efforts have helped to restore some populations in protected areas today. The buffalo remains an iconic symbol of the American West and the Interior Plains.