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Experts Have No Idea Why Grizzly Bears Rampaged Through Yellowstone Area Campground, Killing One


Wildlife officials have no idea why a quartet of grizzlies roamed through a Forest Service campground, attacking three campers and killing and partially consuming one. Top photo is the tent of the fatal victim, Kevin Kammer; middle photo is the campsite were Deborah Freele was staying, and; the bottom photo is the tent of Ronald Singer.

Wildlife experts have no explanation for why a grizzly sow and her three cubs rampaged through a campground outside Yellowstone National Park late last month, attacking two campers before killing and partially consuming a third.

A 70-page report released Monday portrayed a sow intent on killing humans in a campground that, while in the heart of grizzly territory, had not encountered any bear problems this year and which had been properly maintained and kept clean so as not to lure bears.

While a medical analysis (necropsy) of the sow showed her to be somewhat light in weight and infested with parasites, that alone did not explain why she led her cubs on a predatory attack on the Soda Butte Campground in the Gallatin National Forest just beyond Yellowstone's northeast entrance.

"There is no clear explanation for the aggressive, predatory behavior of this adult female grizzly bear in the early morning hours of 28 July 2010," concluded the investigative team, which included representatives from state and federal wildlife agencies and also included Dr. Stephen Herrero, a University of Calgary professor who long has studied the behavior of black and grizzly bears. "The bear and her offspring were low in body condition but their body condition was not outside the range of other wild grizzly bears in the Yellowstone ecosystem."

For campers heading into bear territory in the weeks and months ahead, the report reads ominously, describing a scene where campers evidently did everything they should when staying in grizzly habitat and yet still fell victim.

The sow presumably led her three yearlings through the Soda Butte Campground in search of food. Within a period of perhaps two hours they attacked three tents, were chased or scared off from two, and then succeeded in killing a camper who had pitched his tent about 180 feet from anyone else -- and approximately 600 yards from where the first two campers were attacked.

In the early morning hours of 28 July 2010, an adult female grizzly bear accompanied by 3 yearlings attacked 3 separate people in 3 different tents in the Soda Butte Campground. The initial attack was inflicted on Mr. Ronald Singer at approximately 0200 hours, who was bitten through his tent on his lower left leg. Mr. Singer punched the bear several times and the bear left. The second attack was inflicted on Mrs. Deborah Freele at approximately 0215 hours; she was initially bitten on her upper left arm and then bitten on her lower left arm. She then received a slight bite to her left leg and then the bear left. The third attack was inflicted on Mr. Kevin Kammer at an unknown time, presumably after the first 2 attacks. Mr. Kammer was camping by himself, and was killed and partially consumed at his campsite. All of these attacks occurred in the 27-site campground, of which 24 sites were occupied by people on the night of the attacks.

While the 15-page report, supported by another 55 pages of reports and interviews, raised possible motivations for the bears' behavior, the authors did not pinpoint any as a cause for the attacks. The 216-pound sow had apparently not been conditioned to connect humans with food; analysis of her hairs indicated that her diet had been almost exclusively vegetative for the past two years, and; campers were careful with food storage -- "there was no evidence of improper food storage problems anywhere in the campground at the time of the attacks or prior to the attacks, nor was there evidence that bears obtained garbage or human foods in the campground in 2010."

And yet, the bears seemed intent to find human prey when they entered the campground, which is set amid stands of spruce and pines, and moved from tent to tent to tent before succeeding in killing Mr. Kammer, a 48-year-old Grand Rapids, Michigan, man. The man's body, which had been pulled through a hole in his tent and then dragged about 10 yards from his tent, was found shortly before 4:30 a.m. by law enforcement officers who were clearing campers out of the campground.

In all three incidents, the bears had bit or ripped through the tent fabric to reach the campers, according to the report. While it was not clear whether the sow alone killed Mr. Kammer, the investigators said the evidence indicated that the yearlings partially consumed the man.

Bears had been visible in the immediate area in the days leading up to the attack, according to the report. A subadult grizzly, which investigators determined was not involved in the attacks, had been photographed three days earlier; paw prints of an undetermined bear species had been seen on some of the campground's bear boxes and garbage bins, and a week before the attack a jogger spotted a grizzly sow with three yearlings about 9 a.m. between Yellowstone's entrance and the hamlet of Silver Gate.

"A grizzly bear with 3 yearlings came out of the woods and onto the highway," the report noted. "The mother stood up, then charged Elaine Sabo. She screamed at the bear, 'Hey, hey, hey,' and the bear stopped. The bear and her yearlings then ran into the woods and Ms. Sabo returned to the northeast entrance station. This sighting is approximately 4-5 air miles west of Soda Butte Campground."

Interestingly, DNA analysis of hairs collected by investigators indicated that a fifth grizzly had been in the campground, though not necessarily during the attacks. The hair was found in one of Mrs. Freele's shoes, and the investigators guessed that she might have picked it up sometime during the previous 13 days that she had camped there.


Wow that's amazing. It makes you wonder what should you do if you are one of the first two people then? Should you try to drive/walk around to warn other people there? I'd feel horrible if I was one of the first two people and then there was someone else not so fortunate... But I see some people did drive around, they just didn't drive to the other loop which happened to be where the fatal attack took place.

While there was no evidence that people had food in their tents, what are the chances that someone decided to sleep in the same clothes they cooked in?

My husband and I just returned from a 5 week motorcycle trip which included tent camping in Grand Teton Nat'l Park. There are numerous warning signs posted everywhere and bear boxes for storage. We stores everything in our bear box during our three day stay. The ranger indicated that as long as we follow the suggestions that we'd be fine. Our last night there at around midnight I woke to the sound of a bear trying to get into a dumpster not far from out site. Within 10 seconds he was outside our tent breathing heavily. I was terrified and remained motionless. I thought at any second the bear was going to rip open the tent and attack. My husband was sound asleep next to me... I didn't want to speak a word or make any sound so I just laid there praying that something would distract the bear so we could flee. Nothing. The breathing of the bear continued for what seemed like an eternity. I believe it was around 5 minutes later when my husband stirred and I covered his mouth and whispered that there was a bear outside out tent that the breathing stopped. I couldn't figure out why the bear stayed and breathed but didn't attack for 5 minutes. What's with that. Scarriest time of my life. Don't know if it was a grizzly or black bear but the breathing sounded like it came from a very large bear. I'm so grateful he moved on. My darn husband slept through the whole thing!

I was in Glacier National Park when this happened. There were 3-4 grizzly encounters at Glacier that week as well. All encounters were "maced" by the campers, but the campers were not hurt by the bears. My friend and I were hiking the trail at Glacier and came within 100 yards of a black bear. It crossed in front of us, did not look at us, but continued down the path. We saw 2 more crossing on a range below from where we were hiking later in the day. Then we drove to Banff National Park and saw three more black bears. I have been going to National Parks for the last 20 or so years and to see that many in a weeks time is amazing!

Your bear encounter reinforces our decision to keep bear spray on us even in our tent overnight. While we were in Glacier last month, camped in the Two Medicine area, I was awakened at dawn by something moving around in our campsite. I unzipped the window of our tent and saw that our visitor was a moose! Granted, a moose on the rampage is something I do not want to mess with but my first thought was definitely B-E-A-R!!!

I agree, Linda S., this year seems to be a bad bear year. Also, lots of Grizzly sows are having 3 cub litters, which is rare. Bear populations are increasing.

I'm not a hunter, but the hunters I do know are getting older and don't hunt anymore. The younger generation doesn't care to hunt. They can hunt in video games, from the comfort of their own homes without having to field dress it. I think this leads to more wildlife and more problems. I saw on, the NPS is hiring Elk Reduction Workers in North Dakota. I wonder how long it will be before they are hiring Bear Reduction Workers for MT and WY?


Nothing here seems to suggest that more bears means more aggressive bears.

Just the other day there was an attempted attack on the Blue Ridge Parkway at peaks of Otter. A male bear tried to attack 3 young cubs and momma came to the rescue. Her and the male bear fought for quite awhile before she won and chased him off. But she was so riled up that she then turned on 3 joggers that were coming by and ran them down. Luckily some friends of my parents were right there and opened their car doors so the joggers could jump in.

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