Video shows grizzly running for its life in Yellowstone. See what it was fleeing from

A grizzly bear was spotted running for its life in a wild Yellowstone National Park video — but what could it have been running from?

Tour guide Bo Welden captured the chase and encouraged his Instagram followers to guess what kind of animal the “grown grizzly” was fleeing in a Sept. 21 post.

The video shows the grizzly running near a river with text over the video that reads: “What animal do grown grizzly bears run from? What’s your guess?”

Some said they figured it must be an angry mother moose or perhaps a pack of wolves.

Then an angry bison — tail raised — shows up behind the bear as it flees at breakneck speed. It isn’t just any bison — it’s an angry mother, Welden explained.

“I guessed Mama moose, then saw the Mama bison (and) thought yuuuup,” someone said in the comments.

Someone else commented on how dangerous bison must be for a grizzly to run from one.

“If bears run from Bison you’d think the tourists at Yellowstone would stop trying to pet them,” they said, referring to the record number of videos showing tourists approaching bison in the park over the summer.

“A mother bison showed this grizzly bear that he is not the biggest baddest beast on the landscape,” Welden said. “It was truly AMAZING to be able to witness this role reversal while on tour with @jacksonholeecotours with guests! We were stunned to see this moment in real time.”

Welden told FTW Outdoors the bear was just “around the corner” from the bison herd of mommas and newborn calves in early summer, when the “red dog” calves are most vulnerable to predators.

Welden told the outlet he later spotted the bear feeding on the carcass of a young bison it discovered nearby. “A wise choice compared to attempting to kill a red dog that still had a protective mother around,” he said.

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