Asked in Chickens and Roosters
How can you keep roosters from peeking feathers out of 1 hen he keeps picking on her no others and she is bald?
Feed and grain outlets sell anti peck products used to help stop and heal this problem however the problem may persist even after treatment.
If most of the damage is done at night while roosting you may want to separate the hen for a few days. Also consider putting up an extra roost,as she may move away from the bully. She is probably weakening from prior attacks and now is the target for all. Adjust lighting in the coop as any light getting in will cause pecking. Coops need to be as dark as possible for the birds to settle down.