A grizzly that accidentally inflicted itself with a burst of pepper spray while attacking a hiker in Wyoming’s Grand Teton National Park won’t be captured or killed because it may have been trying to protect a cub, park officials said in a statement.

While mauling a hiker on Signal Mountain, the grizzly bit into the man’s can of bear repellent and was hit with a burst of it, causing the animal to flee. The 35-year-old Massachusetts man, who’d pretended to be dead while he was being bitten, made it to safety and spent Sunday night in the hospital.

There was no word when Signal Mountain or a road and trail to its 7,700-foot (2,300-meter) summit would reopen after being closed because of the attack. Such closures are typical after the handful of grizzly attacks on public land in the Yellowstone region every year.

The decision not to pursue the bears, which officials determined behaved naturally after being surprised, also was consistent with attacks that don’t involve campsite raids, eating food left out by people, or similar behaviors that make bears more dangerous.

Rangers track and study many of the Yellowstone region’s 1,000 or so bears but weren’t familiar with the ones responsible for the attack Sunday afternoon, according to the statement.

The attack happened even though the victim was carrying bear-repellant spray and made noise to alert bears in the forest, the statement said.

Speaking to rangers afterward, the man said he came across a small bear that ran away from him. As he reached for his bear repellant, he saw a larger bear charging at him in his periphery vision.

He had no time to use his bear spray before falling to the ground with fingers laced behind his neck and one finger holding the spray canister.

The bear bit him several times before biting into the can of pepper spray, which burst and drove the bears away.

The man got to an area with cell phone coverage and called for help. A helicopter, then an ambulance evacuated him to a nearby hospital.

Investigators suspect from the man’s description that the smaller bear he saw was an older cub belonging to the female grizzly that attacked. Mother bears aggressively defend their offspring and remain with them for two to three years after birth.

Park officials didn’t release the victim’s name. He was expected to make a full recovery.

Recent grizzly attacks

The attack in Grand Teton National Park came just days after a man in Canada suffered “significant injuries” after being attacked by a grizzly bear while hunting with his father.

Last fall, a Canadian couple and their dog were killed by a grizzly bear while backpacking in Banff National Park. Just weeks before that, a hunter in Montana was severely mauled by a grizzly bear. 

Last July, a grizzly bear fatally mauled a woman on a forest trail west of Yellowstone National Park. The bear was later euthanized after breaking into a house near West Yellowstone in August. 

Also that month, a 21-year-old woman who was planting trees was seriously injured by a bear in British Columbia. Canadian officials could not locate the animal but believe it was a grizzly bear that attacked the woman.

Grizzly bears in the 48 contiguous states are protected as a threatened species, according to the U.S. Fish and Wildlife Service.  

Last month, the U.S. National Park Service announced it was launching a campaign to capture grizzly bears in Yellowstone Park for research purposes. The agency urged the public to steer clear of areas with traps, which would be clearly marked