All of a sudden my flock of hens has decided to gang up on my only Cochin bantam and I'm sure that they are determined to kill her. This cochin was here long before these other hens. She's one of the only left in my original flock. Newly mature hens are picking on her as well as older hens that have been with her for years. I've never seen violence like this before. I knocked two of them off of her with a broom and when she ran and hid in a nest box, one more ran after her and jumped in the nest box on top of her! The back of her head is bald already. This little hen has isolated herself in a horse stall. I gave her her own food and water. I have the rest locked in the coop today so this gal can get fresh air and sunshine without fear of attack, however, she is afraid to come out of her stall. I'm not sure what to do, or why this happened? I did lose my rooster recently, do you think he was keeping the peace and with him gone its now total mayhem? What if they single out another and do this again?