We have a >1 year old hen who has been missing a patch of feathers on her back for a couple weeks now. When we first got her, she was the smallest of the bunch and had a patch of feathers totally missing from her neck, but those have fully grown in now. While all of our hens occasionally peck at each other, it never looks like enough to have done this much damage. We also have a male turkey who occasionally tries to mount the hens. Perhaps the damage could stem from this? I'm also thinking it might be some kind of mites or fungus. The birds eat layer pellets and life in a pretty big barn with straw bedding. They roam freely around the yard during the day and get plenty of exercise. I've included a couple pictures below -- it was raining today so the bare spot is pretty pronounced with all her other feathers matted down. (You might also notice a bit of frostbite on her comb, but that's been clearing up -- it was a hard winter!) What would you recommend we do? If it's a matter of other birds picking on her, we could just isolate her until the feathers have a chance to grow back, though I don't think she'd like this. If people think this looks like some kind of mites or fungus, what kind of powder or spray should we get? Thanks for your help everyone!