11. From hunter to conservationist, Teddy Roosevelt helped save bison from extinction. In 1883, Teddy Roosevelt traveled to the Dakota Territory to hunt bison. After spending a few years in the west, Roosevelt returned to New York with a new outlook on life. He paved the way for the conservation movement, and in 1905, formed the American Bison Society with William Hornaday to save the disappearing bison. Today bison live in all 50 states, including Native American lands, wildlife refuges, national parks and private lands. 12. Bison can live up to 20 years old. The average lifespan for a bison is 10–20 years, but some live to be older. Cows begin breeding at the age of 2 and only have one baby at a time. For males, the prime breeding age is 6–10 years. Learn how Interior works to ensure genetic diversity and long-term viability of bison.