Despite recent high-profile attacks by grizzly bears in the Yellowstone area that have killed two people and left two others seriously injured, wildlife officials say human-bear encounters are not on the upswing, and that such events remain "very, very rare."

The most recent attacks occurred last week at a Gallatin National Forest campground east of Cooke City, Mont., near the northeastern corner of Yellowstone National Park (Land Letter, July 29).

Investigators found Kevin Kammer, 48, of Grand Rapids, Mich., dead at the Soda Butte Campground early Wednesday morning. Two other people -- Deb Freele, 58, of London, Ontario, and Ronald Singer, 21, of Alamosa, Colo. -- were bitten and later treated at a hospital in Cody, Wyo.

Montana Fish, Wildlife & Parks officials, in cooperation with the Gallatin National Forest, the National Park Service, the Park County Sheriff's Office, and the Wyoming Game and Fish Department, worked for two days at the site collecting forensic evidence of the attacks and setting bear traps in and near the campground.

The attacks were traced to a 225-pound female grizzly, which was euthanized, while her three yearling cubs were sent to Zoo Montana in Billings.

An autopsy was performed Friday on the sow to determine if any physical condition or ailment contributed to her predatory behavior. Results of those tests are pending, but officials have confirmed that the bear tested negative for rabies.

"The preliminary results don't show anything unusual," said Montana Fish, Wildlife & Parks spokesman Ron Aasheim.

Under Interagency Grizzly Bear Committee Guidelines, an agreement among eight state and federal agencies, grizzly bears that display unprovoked aggressive behavior toward people or substantially injure or kill people should be euthanized.

And while the recent attacks have raised the specter of a surge in bear maulings, federal and state wildlife officials say there is no cause for concern.

"There's been no change in normal behavior, no increase in encounters and no movement into human-use areas," said Chris Servheen, the grizzly bear recovery coordinator for the Fish and Wildlife Service.

Aasheim, the Montana FWP spokesman, said aside from last week's brutal attacks, this year has been pretty typical with respect to bears. Since May, the agency has relocated more than 30 bears and has had reports of more than 100 bear encounters, he said.

Officials did acknowledge, however, that the Yellowstone attacks were unusual in that no food was found in the tent of the dead man or in the tents of the two injured victims. Grizzlies typically attack because of surprise encounters, to defend of their young, or to defend a food source. But investigators have said none of those scenarios apply to last week's attacks.

An interagency team convened to look into the Yellowstone incident is expected to release its findings within a couple of weeks, Servheen said, adding that, "At this time, speculation about why this happened would be irresponsible because we don't have all the facts yet."

Asked if officials had any idea why the attacks occurred, Aasheim said, "Absolutely none. We are baffled."

But Jeff Welsch of the Greater Yellowstone Coalition predicted there would be more conflicts between grizzlies and people in the future, in part because of ecological changes wrought by climate change. For example, he said, whitebark pine trees, a primary food source for the bears, has functionally disappeared from 85 percent of its range in the Greater Yellowstone Ecosystem because of climate change, forcing bears into lower elevations.

Also, because of generally warming temperatures, bears are denning later in the year and emerging earlier, he noted.

"There's just more opportunity for conflict," Welsch said.

Second fatal encounter

Last week's attacks were the second fatal encounter between grizzlies and people this summer in the Yellowstone area.

In June, a 430-pound adult male grizzly that had recently been released by members of the Interagency Grizzly Bear Study Team, which is responsible for monitoring Yellowstone's grizzlies, mauled 70-year-old Erwin Frank Evert, a botanist from Park Ridge, Ill. The victim was on a hike from his cabin, located about six miles from Yellowstone's east gate in Wyoming (Land Letter, July 22).

That incident was the first fatal attack by a grizzly in the Yellowstone area in a quarter-century. The last fatality had occurred in 1986, when a photographer got too close to an adult female bear in Yellowstone National Park's Hayden Valley.

After the June attack, wildlife officials initially attempted to capture the bear, but later decided to kill the animal after those attempts failed (Land Letter, June 24).

Another human-grizzly encounter made headlines last week when celebrity zookeeper Jack Hanna, who is director emeritus of the Columbus Zoo in Ohio, used pepper spray to ward off a 125-pound grizzly bear cub as he was hiking in Montana's Glacier National Park (Land Letter, July 29).

While such encounters serve to heighten media attention and stoke public fears about bear attacks, Wyoming Game and Fish spokesman Eric Kezsler said there have not been more encounters than usual this year. Nevertheless, he said, conflicts between bears and people could become more common as Yellowstone's bear population, now estimated at about 600 bears, continues to increase.

"As that population grows and expands, their territory will be expanding out to places with more human activity, so we would expect more conflicts with humans as that happens," he said.

Even so, the incidence of human-bear encounters remains relatively small. More than 62 million people visited Yellowstone National Park from 1980-2002, but there were only 32 injuries caused by bears during that time period. Park officials estimate the chance of being injured by a bear while in the park is approximately 1 in 1.9 million.

In developed areas, grizzly bears injured an average of one person a year from the 1930s through the 1950s, but that number rose to four annually during the 1960s before tapering off again to one injury every two years during the 1970s. From 1980 to 2002, there were only two grizzly bear-caused injuries to people in developed areas.

Bear-related injuries in backcountry areas, a rare occurrence before 1970, increased to an average of approximately one per year during the 70s, 80s and 90s, a trend attributed to increased popularity in backcountry recreation.

Click here for the Interagency Grizzly Bear Committee guidelines.

Gable is a freelance journalist based in Colorado Springs, Colo.

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