Although this article centers on the Yellowstone area, it includes lots of good general information on grizzly bear diet and and population management . . .
High above the trees, in the rocky slopes of the Absarokas, one-calorie morsels scurried from the light. They crawled under rocks and in dark shadows. The army cutworm moths come from as far as Kansas and Nebraska where farmers curse them as an agricultural pest. In the Absarokas, they’re something very different: one of several key ingredients to the survival of the grizzly bear.
One day in late July, Cody science teacher Dale Ditolla watched as nine bears gathered in the talus of a mountain bowl, miles outside of Meeteetse. The bears looked like dogs in search of buried bones. They lifted and heaved stones the size of frying pans between their legs, sending them tumbling down the mountainside. Their salad plate-sized paws swiped at scampering moths.
Counting multiple grizzlies at this site is a relatively new trend. Few lived in this part of Wyoming 30 years ago.