As the bison rut runs strong across North America, the U.S. Fish & Wildlife Service is urging the public to be cautious around the massive animals as they compete for females. During this period, male bison grunt, headbutt, tail flag, and more to impress females and compete with other males. Though it is an incredible sight, bison can be incredibly dangerous and should be treated with extreme respect. Bulls can be especially unpredictable and aggressive during the mating season, so stay in your car and respect the wildlife.
Bison Rut
Bison rut, or bison mating season, tends to run from June to September, with bulls mating with multiple females throughout the period. Bulls join mixed-sex groups in early June to compete for mating opportunities, displaying aggression through bellowing, wallowing, and threat displays. Unlike harem-forming species like elk, bison bulls remain in large groups during the rut, except during tending bonds.
Higher copulation rates are linked to larger, more dominant males, preferred by females. During the rut, bulls can loose up to 12% of their body weight, or up to 200 pounds. Reddish-orange calves are born after a 285-day gestation period.
Basic Bison Facts
- Bison are the largest land mammals in North America with males weighing up to 2,000 pounds and standing up to 6 feet tall.
- They primarily feed on grasses, weeds and leafy plants.
- Bison have an average lifespan of 10-20 years.
- Predecessors of modern bison reached North America during the middle of the Pleistocene between 300,000 and 130,000 years ago.
- Tens of millions of bison once thrived across all of North America, with populations stretching from northern Mexico to Alaska, California to New York.
- Bison have poor eyesight, but their sense of smell and sense of hearing are both excellent.
- Bison congregate in herds of varying size and composition.
Safety Guidelines:
- Bison are, like any wild animals, are unpredictable.
- Keep a distance of 100 feet from bison at all times.
- If you encounter bison within 100 feet of the road, stay inside your vehicle.
- Use established gravel or paved pull-outs to park completely off the road when viewing bison.
