Hunger and internal parasites afflicted a grizzly bear that mauled three campers near Yellowstone National Park, but investigators said Monday those factors failed to explain such aggressive predatory behavior.
The bear’s late-night rampage through a crowded campground was the most brazen by a Yellowstone grizzly in a quarter-century. It left one man dead and two people with serious injuries.
But, after an in-depth investigation, wildlife officials on Monday produced a 70-page report that left unanswered a crucial question: Why did the bear attack?
“The reality is grizzly bears are predators,” said Warden Capt. Sam Sheppard with Montana Fish, Wildlife and Parks, who helped produce the report.
“You never know when they’re going to revert to a predatory response.”
Kevin Kammer, 48, of Grand Rapids, Mich., was killed, and two people were hospitalized after the 216-pound grizzly tore into their tents in a nighttime attack on July 28 at the Soda Butte Campground near Cooke City. There was no evidence of food left out by campers that might have attracted the bear.
The grizzly was captured a day later at the same campground, then was euthanized. Its three cubs are now at ZooMontana in Billings.
Deb Freele, 58, of London, Ontario, suffered leg and arm wounds when the bear ripped into her tent and bit her. As she continues physical therapy to regain the use of her arm, Freele said Monday that she had hoped investigators would come up with an explanation for the attack.
“It leaves me unsettled,” she said. “There’s nothing I can think of doing, outside of not going camping there, that would have changed the outcome.”
Wildlife officials have said the animal appeared to be targeting humans and Monday’s report said, “The bear(s) consumed a significant portion of Kammer’s torso.”
“In some cases, the bear apparently reached under the rain fly and bit through the tent or the insect screen of the tent to reach the campers inside,” the report said.
During the investigation, a seven-member team of state and federal officials and an independent bear expert from Canada looked at the bear’s diet, health, past behavior and the condition of her three cubs.
DNA tests on strands of hair found at the campground linked the mother bear to the attacks. And a vegetarian diet was blamed for the mother grizzly’s poor body condition, which the report said was “made worse by a load of parasites found in her small intestine.”
Otherwise, nothing stood out, said Chris Servheen, a grizzly researcher with the U.S. Fish and Wildlife Service.
Tests for rabies and other diseases came back negative after a necropsy.
The grizzly and her cubs had been seen around the Cooke City area at least twice in the weeks leading up to the attacks. Rumors have since floated around the community that a photographer had been baiting bears in the area with food.
Those rumors remain unsubstantiated, investigators said Monday. And there was no sign the attacking grizzly had become habituated to humans, which is often to blame when bears have run-ins with people.
The necropsy suggested the bear had not eaten human food for at least the last two years. That conclusion was based on a carbon isotope analysis of hair, blood and serum from the bear that showed very low levels of types of carbon common in human and pet foods.
Bear specialist Kevin Frey with Montana Fish, Wildlife and Parks, said the findings underscored that, even though bears are omnivores — eating everything from pine nuts to ants to elk — they are still predators that can act as carnivores.
“She obviously was hurting for higher value foods. What caused her mentally to do that, we don’t know,” Frey said.
“There are a lot of bears that are nutritionally challenged at times that don’t exhibit that type of behavior.”