I have one little banty hen who has taken it upon herself to preen the other chickens' facial feathers, sometimes to the point of pulling them out! Weirdly enough, the other chickens stand there and zone out, enjoying this attention. I've even seen them standing there waiting their turn, the little nutjobs. The preening hen never draws blood or pecks facial skin. Any chance you've got an over-enthusiastic face preener in your flock?

I'd never had a hen do this before, and it's just our one little hen who does it.

I'd also check your food & water dishes--is she by chance just keeping the feathers worn down? Is there enough room in the dishes for her to get her head in there? We recently had to build a bigger feeder for our big chickens, my big rooster was having trouble fitting his head & comb in the standard feeder.

I'd say take a chair out and spend some time watching her at different times, and if something odd is happening, you should spot it.

Velvet ~:>