Grizzly deaths puzzling

Bear biologists are refraining from assigning a single reason for a two-fold increase in the rate of natural grizzly bear deaths. Ten of the 16 grizzlies that have met their ends this summer have died of natural causes, according to data from the Interagency Grizzly Bear Study Team. Historically, humans are to blame for more than 75 percent of the bear deaths in the first half of the summer. While the rate is just 37 percent this year, it is derived from a small sample size, and biologists aren’t jumping to any conclusions. “We should be careful not to make too much of this,” said Frank van Manen, team leader for the group. “We’re seeing the typical range of conditions that we’d see with grizzly mortality. “The fact that there were two females with cubs that were killed inflates the numbers a little bit,” van Manen said. “We’re seeing an aging of the population as well. It wouldn’t surprise me if we start to see more of these bears dying from old age.” A major increase in natural mortality could have bearing on policy. The study team is tasked with conducting research that will determine whether Greater Yellowstone Area grizzlies retain “threatened” status under the Endangered Species Act. In November, the 9th Circuit Court of Appeals prohibited the federal government from pulling ESA protections. The court upheld Judge Donald Malloy’s ruling that the U.S. Fish and Wildlife Service failed to account for the potential harm to grizzlies from the decline of whitebark pine trees...more