Pretty much since I got her at 2 weeks old, this RIR chick has been exibiting this behavior. Once I figured out why the others were bald on their backs, I separated her, but each time I try to reintroduce her, she immediately goes back to doing it and will now peck any of the 5 week old chicks she can get close enough to do so. They don't even have to be the bald ones...she pulls out and eats any feathers she can get. I read an few old threads that sound pretty discouraging. I do have 3 adult chickens that would not tolerate such behavior, but I'm not sure that's a safe idea. Any others?