hmm...hadn't considered mites, but I guess it's possible. I was also under the impression that all would have them if one did. But I've also *watched* the #1 hen sneak up behind the others and yank a couple of feathers out of their butts, so maybe it could be both.
Have long been considering diatomaceous earth sprinkled in their dust craters for such an occasion. Have heard that it can cause health issues internally for the same reason it kills bugs externally (sharp micro-edges) so haven't looked real hard for it. Any thoughts on that?
Also, if it's mites, can I use the mite spray I have already (Four Paws brand)? It's intended for cage birds, but my vet also recommends it for raptors. Just wasn't sure if using it on egg-layers would be a problem.
This is definitely not on their backs, pretty much all on their butts (had roosters when we had chooks as a kid, and I know what roo damage looks like).