I recently noticed that my Delaware was loosing feathers around her neck. She is too young to be molting, but has been in with the other chickens since July. We also added a Black Sex Link at the same time. Both the same age. We have 6 chickens a large coop and run area and we let them free range in the afternoon/evening when we are home. We have birds of pray of that live close to our home so they are not safe to free range when we are not in the yard with them. I came home the other afternoon and found my Delaware laying in the run with all the feathers on her head missing and a huge gash from the top of her head to the base of her neck. The gash was so deep I could see muscle. I tried to to nurse her back to health, but she never came too and died a few hours later. I was devastated. I have since her death, only a few days noticed feathers missing on the neck and head of the Black Sex Link. I am giving my two New Hampshire Reds away, They are the only ones who are never missing feathers out of the group. I have observed their aggressive behavior toward the other hens, but never dreamed they would kill. My other chickens have stopped laying completely. I have two black asutrolops and one silver lace Wyondott. All seemed very friendly, but will no longer let me pet them in the yard like they used to and seem very nervous. Will they be ok once the Reds are removed? I know that the whole pecking order thing will have to take place again because there will be a change in the flock, but will the remaining chickens pick up the habits of the Reds? Do I need to start all over with new chickens? I have read that the other remaining chickens are usually docile and easy to keep. I am hoping that by removing the other two things will improve quickly. I just wish I had figured out what was going on before I lost my Delaware. She was the sweetest most dog like chicken ever!!!! Any suggestions would be greatly appreciated. I would like to replace the Reds with more Sex Links, or Buff Orpingtons. Please help.