I live in a small town with woods and hiking trails. My neighbor just called this morning to say she came upon 2 raccoons having a vicious fight. One raccoon killed the other and then came after her and her 2 dogs. Thankfully her dogs were leashed and she managed to get out of there without anyone getting hurt. She was very shaken and called to warn me about walking my dogs back there because she was afraid the attacking raccoon was rabid. I don't know about anyone else's backyard but we have had bears in ours. We also have skunks passing thru. I volunteer at our local SPCA and we hear from desperate people who have had their dogs stolen out of their yards. You do need to supervise your dogs for their own safety.