A Bear is sort of like a Big untrained Wild Dog. in other words you have to be prepared for anything

 They can be territorial like Grizzly bears and attack and kill you because they consider you to be a food competitor and they don't want to starve. Or they can be more like a black bear which mostly doesn't want anything to do with you and run away. I have mostly had the black bear experience. My only experience with a Grizzly Bear as in Yellowstone national Park where it was a beautiful day and it was in a meadow eating flowers sort of like a Flower child out of the 1960s and very mellow. But, then a ranger arrested someone for getting too close to it because the Ranger didn't want the Bear to kill him or something. So, Rangers make people keep their distance from Grizzly bears so they don't get killed by accident.

However, the animal most likely to kill tourists is not a Grizzly Bear it is actually a Buffalo. They are herd animals and don't run away because their safety is the herd. So, a male Buffalo is programmed to kill anything including wolves or bears rather than to run away. The tactic they use is sort of like a Rhino where they knock someone down with their horns and head and then smash the person's chest and head with their front hooves. So, a Buffalo only takes a few seconds to kill someone if they get too close to that Buffalo. Because Buffalo Males will not run away they will fight you and maybe kill you instead unless you run away or climb a tree or get into your vehicle if you have one when you see one.