Yellowstone National Park‘s bison population is the largest on public land in the United States. The park’s bison exhibit wild behavior like those of their ancient ancestors, congregating during the breeding season to compete for mates. Yellowstone is the only place in the nation where bison have lived continuously since prehistoric times presenting visitors with a top opportunity to view the most important bison herd in the country.
Updated 21 September 2026 — the numbers behind the herd
Yellowstone recorded 4,762,988 recreation visits in 2025, just short of its 2021 record. The park’s bison were estimated at about 4,550 before the 2024 calving season and genetic work published in March 2025 confirmed they now function as a single interbreeding population. Bison injured two visitors in 2025; the first incident of 2026 came on 26 June, when a 12-year-old was hurt near Mud Volcano. The 25-yard rule has not changed.
Bison are North America’s largest mammal, weighing up to 2,000 pounds. They’re both quick and agile too, running three times faster than people. One bison is an intense sight on its own. An entire herd of bison stampeding through a traffic jam, like we see in the video below, is on its own level.
Drivers in Yellowstone are asked to drive cautiously and keep an eye out for wildlife. Bison and other animals are common sights near and on the park’s roadways. In cases where they do show up on the road, they should always be given the right of way. If you encounter a wildlife jam, you’re asked to stay in your car. Read more on bison safety in Yellowstone National Park below.
Yellowstone National Park Bison Safety:
Bison have injured more people in Yellowstone than any other animal. Bison are unpredictable and can run three times faster than humans. Always stay at least 25 yards (23 m) away from bison.
- Give bison space when they are near a campsite, trail, boardwalk, parking lot, or in a developed area. If need be, turn around and go the other way to avoid interacting with a wild animal in close proximity.
- Approaching bison threatens them, and they may respond by bluff charging, head bobbing, pawing, bellowing, or snorting. These are warning signs that you are too close and that a charge is imminent.
- Do not stand your ground. Immediately walk or run away from the animal. Spray bear spray as you are moving away if the animal follows you.