This is what happened with my girls. I had one feather eater, rather obvious, she was the only one with all her feathers. I sold her w/ a caveat to the new owner. He says no problems. Probably because she was no longer head hen. This girl would stand down a rooster. Anyway, I tried aprons, but then the picking moved to the wings, my NH has only about half her wing feathers, and the EEs are picked across the bow. So, with Goldie gone, I am now seeing a very few pin feathers growing back on the bare skin. My Marans is the most obvious, they are about 3/4" long and black, but the skin is no longer red. I tried moving Goldie to another flock to knock her down a few pegs and stop the behavior. Didn't work, so I sold her after 3 days and and seeing feather damage on my NN.
My suggestions are to isolate the chicken/chickens with the most feathers. Hopefully you have only one or two instigators. If not, I think you said you have a large coop. If you have space, or can make cages, try isolating each one from dark to dawn. They don't need food and water during sleep time. I never noticed any picking going on during the day time when they were out and about, so I presume it was at dusk while the settled for the night and in the morning before we let them out. Or they just didn't pick when I was there.
If you try peepers again, use the largest ones w/ a pin. Goldie took 48 hours to get the pinless peeper off.
There probably won't be much regrowth until the next molt. I have pictures in my mind of 5 nearly naked hens this fall. The NH has less feathers now than she did at the the peak of her molt last fall.
Like you I have ruled out diet, I get good organic feed (when I switched I swear I could hear them saying "Oh... Nom, Nom, NOM!" No billing waste either), feed excess eggs back 2x or a week, plus any protein from leftovers. They also get a variety of 'fresh' fruits and veggies from the produce dept waste barrels daily. Gave them Manna Pro suppliment for good feather health. They free range most mornings (too many predators to let them hide in the woods during the heat of the day).
I think the picking has stopped since the new girls, POL pullets, show no feather damage.
My suggestions are to isolate the chicken/chickens with the most feathers. Hopefully you have only one or two instigators. If not, I think you said you have a large coop. If you have space, or can make cages, try isolating each one from dark to dawn. They don't need food and water during sleep time. I never noticed any picking going on during the day time when they were out and about, so I presume it was at dusk while the settled for the night and in the morning before we let them out. Or they just didn't pick when I was there.
If you try peepers again, use the largest ones w/ a pin. Goldie took 48 hours to get the pinless peeper off.
There probably won't be much regrowth until the next molt. I have pictures in my mind of 5 nearly naked hens this fall. The NH has less feathers now than she did at the the peak of her molt last fall.
Like you I have ruled out diet, I get good organic feed (when I switched I swear I could hear them saying "Oh... Nom, Nom, NOM!" No billing waste either), feed excess eggs back 2x or a week, plus any protein from leftovers. They also get a variety of 'fresh' fruits and veggies from the produce dept waste barrels daily. Gave them Manna Pro suppliment for good feather health. They free range most mornings (too many predators to let them hide in the woods during the heat of the day).
I think the picking has stopped since the new girls, POL pullets, show no feather damage.