New to raising backyard chickens. We have 4 hens. All was good until about 3 weeks ago when our Rhodie started losing feathers on her lower back. Thought I'd might be establishing pecking order, but not so sure. I think I ruled out mites or lice. Don't noticed anything. I separated her last week but went away for the weekend and put her back in the coop. When I got home she now has a blood spot as if she was pecked. Also, noticed the Ameracana's back feathers are not looking good and a few are missing. Coop run is 10' by 5' , I think. Need to check with my husband. Weather is getting cooler. Feed them 16% layer food and just bought 18 % feather fixer. Can't find anything with higher protein. Separated rhodie again, so others don't peck the open wound. What is happening? Meanwhile, we lost our polish hen. Between a 12 hour period she died. Found her in a nesting box in the morning. She wasn't laying yet. We don't know what happened.