Yellowstone rangers determined that it was a grizzly sow that attacked a 10-year-old boy on a hike with his family/NPS file

No action will be taken against a grizzly sow with at least one cub that attacked a 10-year-old boy who tried to run away from it, Yellowstone National Park staff said Friday.

The boy and his family were hiking Thursday morning up the Divide Trail southeast of the park's Old Faithful complex when the bear charged out of vegetation along the trail, according to park officials. The boy ran and the bear chased after him, knocking him down and biting him on his back and buttocks. He also injured a wrist, according to the park. The boy's parents were able to chase the bear away with a burst of bear spray from about five feet away.

“This incident could have been more serious. We applaud the family for traveling in a group, carrying bear spray, and knowing how to effectively use it during their emergency,” said Yellowstone Deputy Superintendent Pat Kenney. “We wish their son a full recovery from his injuries.” 

Rangers who went to the site of the attack later Thursday determined from tracks the species of bear that attacked the boy and that there was at least one cub in the area. They were probably foraging in the vegetation when they were spooked by the famiy, the park said.

The names of the boy and his three family members, from Washington state, were not released by the park.

Park staff pointed out that all of Yellowstone is bear habitat: "from the deepest backcountry to the boardwalks around Old Faithful." Visitors should be prepared to encounter bears anywhere in the park, they added.

There has not been a reported bear attack in Yellowstone since 2015. On average, one bear attack per year occurs in the park, the staff noted.