Born and Raised in Anchorage Alaska....fished all over the state as a kid, we never, never went into the brush fishing unless we carried at least a 10mm or 44mag hand gun. We also usually carried a 30-06, or 12 gauge with slugs. Bears where we fished were mostly curious, hadn't been around humans, really they wanted our fish for an easy meal. Bears that associate humans with food, or harm, are bad news. IMO, less than lethal would be a mistake, if you don't want to injure the animal, fire a warning shot first. If you should come across a Sow with cubs, get far away as possible, have see some Brown Bears that took and incredible amount of lead to stop. Blacks aren't as big but just as tough.
Bears are beautiful animals and fascinating to watch.....at a distance. Millions of years of survival instincts are imbedded in their small brains. They don't ask questions, if in doubt, they may try to posture or bluff. But when you see the hair on their neck stand up an they flatten their ears against their head....its pretty much game on then. You got some good advice above in other posts. Just my .02 cents.