Once found throughout the western states, grizzly bear territory is now pretty much limited to Yellowstone and Glacier National Park. Grizzly bears, aka North American brown bear, appear on the California State flag, but are now actually extinct there.
Over the last decade, mountain pine beetle infestations have devastated old growth forests in the US. Around Yellowstone and Glacier Park, this has eliminated habitat and food sources for grizzly bears. In search of food and healthy forest, bears are wandering out of the parks, bringing them into closer (and dangerous) contact with humans, with resulting bear deaths dramatically increasing in the last few years.
And we can point to climate change as a major cause of these events. "Extreme cold used to kill mountain pine beetles, but with a warmer climate, the beetles were able to survive the winter, allowing them to kill whitebark pine trees at high rates. Federal scientists last year estimated that an average of 76 percent of the whitebark pines had died since 2002 in the areas of the ecosystem that they regularly survey. Blister rust, caused by an invasive fungi, has also been harming the trees, and drought adds stress."
"More bears died in 2018 in the Greater Yellowstone Ecosystem than in any other year in at least four decades, according to the Interagency Grizzly Bear Study Team. Last year's 69 deaths more than doubled the average in the decade from 2000 to 2010, when about 27 bear deaths were reported each year."