Image via Youtube

Visitors to Yellowstone National Park were sent running for safety when a black bear sow charged them after they crowded her three cubs on a roadway, NBC News reported.

"These tourists were absolutely in danger," Bob Gibson, Montana Fish, Wildlife, and Parks Communication & Education Program Manager, said to NBC News. "Black bears are usually shy of people. But you put them with their cubs and they get really protective. You never want to be between a bear and its cub."

On the video, Yellowstone Park Ranger John Kerr can be heard yelling "Keep going! Go! Go!" as mama bear picked up speed and the visitors rushed to their cars.

Gibson said this could have been a deadly encounter if the cubs were younger. A black bear cub spends about a year with the mother before going off on its own, and near the end of this time, mom becomes less protective of her young. These cubs were about 13 months old. "Had they been the young of the year and 10 days old, the mom would have been all over the tourists," Gibson told NBC News.

Gibson’s advice for Yellowstone visitors is to remain as far away from the bears as possible. This is especially true in springtime when cubs are born and in fall hibernation time, when bears get particularly protective of their food sources.

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