Here's an example of what we see around our house, periodically, on our cameras. Haven't bothered the chickens yet, though if they got it in their heads to our 10kv fence would likely deter them. From what I've heard from others in "bear country," the bears are more interested in whatever scraps (e.g. chicken feed, scratch, other leftovers from chickens) are around than the chickens themselves...though they supposedly will take a chicken if the mood strikes. Bears are omnivorous opportunists, though, so if they have to work too hard to get something, they'll likely move along.