An emergency room nurse was shocked to see two men ignoring safety advice, seemingly trying to pet a pair of bison while posing for photos at Yellowstone National Park last week.
As KUTV reports, Heidi Irby captured the incident on camera and shared it online as a warning to others.
In the clip, which you can watch below, she can be heard warning the men that the bison could kill them, and worrying that she might have to spring into action if the animals decide to charge.
Although they may look docile, bison are wild animals and can be unpredictable. According to the National Park Service (NPS), they have injured more people at Yellowstone than any other animal, including bears and snakes.
Last summer, three people were gored by bison at the park within the space of a month, including a 25-year-old woman who was thrown 10 meters in the air and received a serious puncture wound from the animal's horns.
Bison safety
Yellowstone's bison are one of its star attractions, but Park Rangers warn visitors to always stay at least 25 yards (23 meters) away for their own safety. If you're not sure how far that is, cover one eye, raise your arm, and give the bison a thumbs-up. If you can completely hide the animal behind your thumb, then you're OK.
If you accidentally come across a bison at close range, watch out for behavior like pawing the ground, grunting, making bluff charges, and raising the tail, all of which indicate that the animal is agitated and likely to charge for real.
For more advice, see our guides how to avoid being gored by a bison and wildlife safety: eight tips for unexpected encounters.
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