When I was a toddler, a bear entered the yard where we spent a week or two in the summers. My aunt and uncle had a dalmatian named Rex and they cared for two collies named Laddie and Lassie (hard to believe, but I shit you not). The dogs kept the bear busy and my uncle--since passed on--got into it with the dogs and bear using an axe. The bear left. One of the dogs got hurt a bit and the bear got cut, too. I think the dogs would have driven the bear away without my uncle being there, but I also suspect one or two would have had to be put down.