Rebounding Grizzlies Still Face, and Pose, Risks
Yellowstone's rebounding grizzly bear population is an undeniable success. But figuring out how to manage the threatened omnivores--in light of potential food shortages and deadly human-grizzly interactions--isn't so easy.
Lance Craighead--a conservation biologist who's been involved in grizzly research and debates for a quarter-century and whose father and uncle pioneered grizzly research in America--says the scientific basis for declaring bears recovered entails a lot of uncertainty. "When Yellowstone grizzly bears were petitioned for delisting, the International Bear Association, which is a group of bear biologists worldwide, submitted comments on the delisting proposal that were very precautionary in measure," Craighead says. "They didn't jump on Servheen's bandwagon, and instead pointed out that there were a lot of potential problems--food, population size, climate change. Although Chris likes to believe he represents the majority of bear biologists, I don't think he really does on some issues."
Yellowstone officials believe a grizzly that learns to regard humans as food is a danger too serious to leave on the landscape. That's why they spent weeks trying to find the bear that killed and partially consumed 59-year-old John Wallace this past August on a backcountry trail in the Hayden Valley. Nobody knows how the attack unfolded. Of 13 grizzlies trapped during the investigation, DNA from one female matched that found in a scat sample collected at the scene. Investigators eventually linked the sow to another killing, a month earlier. In July Californians Brian Matayoshi, 58, and his wife, Marylyn, were hiking on the Wapiti Lake Trail when they startled a female with cubs. She moved toward them, and the Matayoshis ran, likely triggering a chase instinct. Marylyn hid behind a small downed tree while the bear attacked her husband, clawing his back and biting his arm and leg, severely damaging his femoral artery. The bear then approached Marylyn, lifted her by her backpack, let go, and left. Brian died from injuries before help arrived. Although park officials determined that the bear acted defensively in a surprise encounter, they euthanized her after hair and scat samples showed that she had been at both crime scenes.
The deaths were the first attributed to bears inside the park in a quarter-century, although the year before two fatal maulings occurred just outside the park. In July 2010 Montana Fish, Wildlife and Parks officers destroyed a sow grizzly that killed a camper. Four bears--an underweight, 216-pound female and her three yearling cubs--entered Soda Butte campground in the early morning hours, though the campers hadn't left out anything that would attract grizzlies. There they attacked sleeping campers, killing one: Kevin Kammer, 48, a father of four from Grand Rapids, Michigan, who was found 30 feet from his tent and partially consumed. When the female returned to the scene, officials trapped and euthanized her; they sent the cubs to zoos. A necropsy of the bear showed a parasite load that, combined with the demands of cub rearing, may have contributed to the sow's low weight. She had probably lived within a few miles of the campsite during her adult life, and sophisticated tests showed that for the previous two years she had eaten an almost exclusively vegetarian diet.
A month earlier a grizzly killed Erwin Evert, a 70-year-old botanist from Chicago who had spent years hiking the wooded ridges of Shoshone National Forest on Yellowstone's eastern edge. Although the details are unresolved, Evert encountered a bear that, just hours earlier, Interagency Grizzly Bear Study Team biologists had trapped, sedated, and fit with a radio collar. It killed Evert with a bite to the head, and Wyoming wildlife officials later shot it.
Four deaths in two summers fueled public interest in grizzly attacks. The popular media piled on, including a fact-challenged article in Men's Journal [[LINK Men's Journal: http://www.mensjournal.com/who-pissed-off-the-bears ]] that all but concluded that starving bears were streaming from the park to eat people. Statistically, the incidents were freak occurrences. Since the 1930s, as Yellowstone Park visitor numbers have skyrocketed from 300,000 annually to 3 million, bear-inflicted injuries to humans have fallen from 175 per million visitors to fewer than one per million.
As rare as they are, gory maulings color public perceptions, though almost all experts dismiss any notion that hungry bears are hunting humans. "There's no connection between any of these attacks and food sources," says Servheen. "We have no reason to believe that bears are seeking people out to eat them in the Yellowstone ecosystem. I think it's irresponsible for people to make conclusions like that. That's crazy."
Craighead agrees. "If food shortage was a real driver, it would be more likely happening early in the spring and late in the fall, when they're urgently looking for food," he says. "Since these happened early in summertime it's not as likely that would be one of the main causes. This doesn't set off any alarm bells for me."
While people aren't likely to be increasingly part of the menu, different foods have come to play a pivotal role in the legal battles surrounding the level of protections afforded to grizzlies going forward.