Tourists put bison calf into car to keep it warm at Yellowstone National Park

Tourists at Yellowstone National Park aren’t supposed to touch the wildlife. In fact, according to the park’s website, they aren’t supposed to even come within 25 yards of the animals.

But one father and son got even closer than that when they put a baby bison in the trunk of their car.

The pair reportedly just wanted to keep the calf warm, according to another tourist.

“They were seriously worried that the calf was freezing and dying,” Karen Richardson told East Idaho News.

READ MORE: The race to save Canada’s wildlife

Richardson was with a group of students at a ranger station in Yellowstone when they drove up, asking to speak to an official.

Rob Heusevelet, a father of a student, warned the pair to let the calf go.

“They didn’t care,” Heusevelet said. “They sincerely thought they were doing a service and helping that calf by trying to save it from the cold.”

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Bison are native to North America, and live in the Canadian Prairies, as well as the central United States, where winters can get to -30C.

Rangers reportedly released the bison calf back to the wild and issued a ticket to the men.