BILLINGS, Mont. (AP) — Grizzly bears are part of life in the gateway communities bordering Yellowstone National Park, and backcountry snowmobile guide Charles “Carl” Mock knew well the risks that come with working, hiking and fishing among the fear-inspiring carnivores, his friends said.BILLINGS, Mont. (AP) — Grizzly bears are part of life in the gateway communities bordering Yellowstone National Park, and backcountry snowmobile guide Charles “Carl” Mock knew well the risks that come with working, hiking and fishing among the fear-inspiring carnivores, his friends said.