1. Bison are the largest mammal in North America. Male bison (called bulls) weigh up to 2,000 pounds and stand 6 feet tall, while females (called cows) weigh up to 1,000 pounds and reach a height of 4-5 feet. Bison calves weigh 30–70 pounds at birth. 2. Since the late 19th century,  Interior has been the primary national conservation steward of the bison. Public lands managed by Interior support 17 bison herds—or approximately 10,000 bison—in 12 states, including Alaska. More than 10,000 bison, including this one in Grand Teton National Park, live on public lands managed by the Department of the Interior. Photo by Jerry Megenity.