I've noticed feathers missing on the back of my 7 month old Americana rooster. The feathers at the bottom of his back, right where the long tail feathers start. Today the whole area was swollen and bleeding. He is in a large coop with 26 hens and another rooster (Rhode Island Red). I was assuming it was the other rooster pecking at him to get off 'his' girls. When I took the RIR out of the coop, the hens started pecking at his back. Now I'm not sure how the problem started or how to take care of it. Any advice would be greatly appreciated.