The bear will not appear to be overly angry. In these cases the best defense, is to display aggressive behaviour towards the bear, by yelling at it, waving a stick at it, throwing rocks at it, etc. You have to demonstrate dominance over the bear. This may seem contradictory to what I have already said, and unfortunately it is difficult to determine what a particular bear's motivation is. If you run into a Grizzly, you are likely in big trouble, but they are not common, except in the far north.
Most bear attacks involve food or surprise encounters.
Random attacks such as the one that killed 2 people at Liard Hotsprings in 1997, are rare. The Environment Ministry receives about 8,000 Bear complaints a year and Conservation officers are forced to destroy about 1,000 troublesome Bears a year, even more in heat wave years like 1998 where food is scarce. Unfortunately, once a bear learns that humans are an easy source of food, they become a permanent threat. For more info on Bears try, The Bear Facts or Bear Watch Home Page . They are quite common in BC, especially on Vancouver Island, and in the Southern Interior around Princeton.