Yellowstone has seen a nearly 50 percent increase in conflict between bears and humans in the past five years: A new report by the U.S. Fish and Wildlife Service comparing Yellowstone with Glacier shows that in 2011 there were 17 people charged by grizzlies in Glacier, while in Yellowstone 62 were charged — nearly four times more. This despite the fact that Glacier’s bear population is far greater, 1,000 bears vs. Yellowstone’s 600.
But even with all those interactions there were just two deaths by grizzly last year in Yellowstone, and throughout the national parks 81 percent of all bear charges resulted in zero injury. Still, the study, along with another one by the USGS, yields a lot of valuable information about why Yellowstone’s bears are more dangerous, and it comes back to a changing animal habitat that’s forcing bears to interact more with people.
For one thing, pine trees in Yellowstone are more endangered than the bears, with white bark pines falling prey to blister rust. That takes away an important part of the bears’ usual diet, pine nuts. And cutthroat trout have also disappeared because of the introduction of predatory lake trout — which can’t be caught by bears because they spawn in waters too deep for bears to fish. What’s left to eat is game…and human garbage.
Which accounts for why the bulk of a grizzly’s diet in Yellowstone is meat, while in Glacier it’s nearly 97 percent vegetarian.
Beyond the dietary constraints on bears in Yellowstone, the conditions of bear-on-people interactions are different as well. In Yellowstone, bears are more habituated to people, which isn’t a good thing, and the USFWS study, going back to 1990, shows that in 38 percent of bear charges human food was present, suggesting that people are too often careless with both their food and their trash.
Further, in the bulk of charges people weren’t carrying pepper spray. And unfortunately in too many instances of fatal attacks the victims ran away from the bears rather than standing their ground, making noise, etc., to scare the bears. Lastly, the most likely victims of charges were lone hikers or lone hunters, suggesting that there really is safety in numbers.
Grizzly photo by Shutterstock