I have three hens, two red and one black, aka Miss Lucille, Miss Maureen and Miss Michelle; the black hen is losing tail feathers and the feathers on the back of her neck and head. There are no scabs and I have not seen the other girls picking on her. They are free range in our backyard, and initially all three spent the night in the coop. Foe the last 4 weeks the black hen has been sleeping on a set of shelves that are also in the backyard. In order to keep her in the coop I have to lock it, which I have started doing now that it is cold in the evenings here in New Jersey. Any thoughts or comments will be appreciated. Also, none of the girls are laying, and there is a 100 watt bulb, shielded, in the coop.