Visiting my backyard is the largest record bear caught by NJ Fish & Game...weighed in at 726 pounds 2 years ago in May. They estimated he would go to 800-1,000 lbs winter weight....before moving here I had NO IDEA a black bear could get that large. We call him 'Mongo' and he's literally the size of a VW Beetle. I promise you that not only is Mongo not human-aggressive but he knows about firecrackers and runs like hell if we even make the motion like we're lighting a pack. He does love hitting up everyone's garbage on trash day so he's familiar to us, and he's wandered through when the girls are out in the yard and showed a definite interest. But we're careful to monitor 'outies' and if he makes a wrong move he gets a faceful of firecrackers. He has never come through in the middle of the night to rip the coop apart though he darn well could, nor has he ever touched my house. I believe that using them has been a great deterrent (10+ years) and has never caused us a problem. Personally I love the seeing the wildlife and I'm (so far) happy at finding a way to be able to co-exist peacefully.