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Video: Bison herd escorts calves across road in Yellowstone
A bison herd filled with calves crossed US-212 in Yellowstone National Park, Wyoming, in late May 2023. Toby Tollefsen recorded this video while on a trip to the park.
YELLOWSTONE NATIONAL PARK - A herd of bison was captured on camera escorting several calves across a road in Yellowstone National Park.
The herd crossed US-212 inside the park in Wyoming in late May, according to Toby Tollefsen, who recorded video of the moment.
The video shows cars pulled to the side of the road as dozens of bison pass by and make their way up a hill.
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Yellowstone, which is home to the largest concentration of mammals in the lower 48 states, has somewhere between 2,500 to 5,500 bison within the park, according to National Park Service officials.
Yellowstone is also the only place in the U.S. where bison have lived continuously since prehistoric times.
The reddish-brown calves are born in late April and May, after a gestation period of 9 to 9.5 months, NPS says.
The herd crossed US-212 inside the park in Wyoming in late May 2023, according to Toby Tollefsen, who recorded video of the moment. (Credit: Toby Tollefsen via Storyful)
"Calves can keep up with the herd 2 to 3 hours after birth and they are well protected by their mothers and other members of the herd," NPS states on its website. "However, wolves and grizzly bears can kill bison calves."
Once they reach adult age, bison are the largest land mammals in North America, with males weighing up to 2,000 pounds and females weighing up to 1,000 pounds, according to NPS. They’re also agile and quick, and can run up to 35 miles per hour, the park adds.
Because of this, park officials remind visitors that the "safest (and often best) view of wildlife is from inside a car."
NPS also warns visitors to stay at least 25 yards from animals such as bison and elk, while keeping a distance of at least 100 yards from bears and wolves.
This story was reported from Cincinnati.