Fight back with a black bear as he will kill you and eat you right then and there..at least partially...NOT with a griz--you are to play dead...you fight back and don't have a weapon you will be dead, period..

Black bear, punch/kick the nose, eyes, whatever...but keep him off of you..black bears can be very predatory at certain times depending on food availability, age of bear, etc....way more black bear attacks than griz, but there are also a ton more black bears than griz..

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Bear Attacks
Bear attacks are rare; most bears are only interested in protecting food, cubs, or their space. However, being mentally prepared can help you have the most effective reaction. Every situation is different, but below are guidelines on how brown bear attacks can differ from black bear attacks. Help protect others by reporting all bear incidents to a park ranger immediately. Above all, keep your distance from bears!

Brown/Grizzly Bears:
If you are attacked by a brown/grizzly bear, leave your pack on and PLAY DEAD. Lay ﬂat on your stomach with your hands clasped behind your neck. Spread your legs to make it harder for the bear to turn you over. Remain still until the bear leaves the area. Fighting back usually increases the intensity of such attacks. However, if the attack persists, fight back vigorously. Use whatever you have at hand to hit the bear in the face.

Black Bears:
If you are attacked by a black bear, DO NOT PLAY DEAD. Try to escape to a secure place such as a car or building. If escape is not possible, try to ﬁght back using any object available. Concentrate your kicks and blows on the bear's face and muzzle.
If any bear attacks you in your tent, or stalks you and then attacks, do NOT play dead—ﬁght back! This kind of attack is very rare, but can be serious because it often means the bear is looking for food and sees you as prey.