CUSTER, S.D. (KELO) — On May 31, a woman in Yellowstone National Park was gored by a bison, and thrown 10-feet into the air. She had approached within 10-feet of the animal prior to the attack.

Bison are wild animals. Even when they are near human spaces, such as roads, parking lots, trails or (as in the case of the Yellowstone incident) boardwalks, they must be seen and treated as wild animals.

Custer State Park, with a bison population of around 1,500, is the place in South Dakota where one is most likely to encounter a bison in the wild. Even here, bison attacks are not exactly rare. For example, a woman was tossed into the air in 2021, another was attacked in 2020 after approaching a calf, and in 2016 yet another woman was gored after approaching a bull.

Custer State Park averages around 2 million visitors a year, says Lydia Austin, Interpretive Program Manager for Custer State Park. She says a large part of the job for those in the park is educating people on wildlife safety.

“We really emphasize what we call the rule of thumb,” said Austin. The park advises staying 100 yards away from wildlife, but as most people don’t carry tape measures or range finders, the rule of thumb can often serve as a substitute.

“It’s really simple. You take your thumb, you stick [your arm] straight out, close one eye, and if you can cover the entire animal, you’re at a safe distance,” Austin explained. “It applies to any animal.”

However, Austin went on to note that even while using the rule of thumb, if the animal changes its behavior due to your presence, you’re likely still too close.

In terms of bison, the signs that you’re infringing on their personal bubble can be fairly clear. “It stops eating; stands up; starts looking at you — you’re too close to it — big signs that you’re really starting to get it agitated: it’s going to start pawing the ground, shaking its head, maybe rubbing against a tree,” said Austin.

A very clear sign that a bison is uncomfortable with you? Its tail goes up. “In the park, it’s charge or discharge,” grinned Austin. “It’s either going to the bathroom or it’s mad.”

If any of these signs occur, Austin says you should begin backing away, creating distance and getting into a vehicle if possible. If you’re on a trail, time to explore your surroundings. “Go around. You don’t have to stay on the trail. Give the animal its distance,” she said.

If charged by a bison, you likely won’t win a footrace against it, with Austin giving them a top speed of about 35 miles per hour. They’re also surprisingly nimble. “They also can turn really quickly,” she said. “They’ll just plant their front feet and swing that behind around — they can turn on a dime.” In short, hiding behind a tree won’t help.

In terms of size, a bison can range from 1,200-2,000 pounds. Dangers include the size and weight of the creature, as well as its hoofs and horns.

While bison in Custer State Park often move in and around human structures, it is important to remember this. Just because they are comfortable approaching you, you shouldn’t feel comfortable approaching them.

Austin emphasizes that there is never a scenario in which a park guest should attempt to touch a live bison. Even if they believe something is wrong with a bison or calf, people should not approach them. Instead, says Austin, call a ranger.

“Go to the visitor center,” Austin said. “Mark it on their phone. Take a picture of the nearest landmark and what you’ve seen — and take it to a park ranger.”