We have lots of black bears here and for the most part they dont bother anything. And if u have an electric fence they shouldnt even try to bother them. I've never heard of somebodys horses getting attacked by a black bear, but my friend has a mare thats blind in one eye and 2 cyotes attacked her. she lived thankfully. But usually the electric fence discourages anything that might happen. and if they did try something they would probably get shocked by the fence and run off.