In a grizzly bear attack, what should you do?

If a bear approaches you, stay calm, talk to the bear, wave your arms, and help it to recognize you as human. Don’t run. Just like a dog, a bear’s instinct is to chase something that flees. If it continues approaching, make loud noises with pots, pans, or sticks, throw rocks at it, or as a last resort use bear spray. If it attacks, your response depends on the type of bear. An easy rhyme to remember is “If it’s brown, lie down. If it’s black, fight back!” Brown bears (grizzlies) will likely leave you alone if they think you are dead. Lie flat on your stomach or curl up in a ball and cover the back of your neck. If it’s a black bear, fight back regardless of the circumstances.

Source: The Hoarding Marmot