I think A combination, of bear resistant design and good fencing backed with electric charge wires is the best idea in bear country. I have only seen one bear in my area in my lifetime, a few years ago. They long ago were hunted to extinction in this area. But a lifetime of wilderness hunting, hiking, fishing and occasionally being stranded in bear country and having family living in bear country, has made me aware of the habits and threats from bears, or other large wild animals, to livestock, pets and occasionally people. Good luck in your efforts to make a safe flock! I applaud your efforts to use non lethal and legal methods to keep your chickens separated from predators! I try to avoid killing pest first, myself. Prevention is most times, better than the cure. I would mention to some folks , that shooting an animal(large) with birdshot is very cruel and ill advised! If it does not kill them quickly, they are likely to suffer a long time and often die after a prolonged battle with pain and infection. More humane to use buckshot and kill them quickly, if you must use that level of control or protection. I saw a neighbor's goat accidently take a single # 7 shot pellet to the head and die instantly, and that was at about 40 yards. (a long story) and I have found animals that were wounded and had suffered a long time from people's ineffective shooting, often with light shot or caliber bullets. I would give the bear a chicken before shooting it with birdshot!