I have some 9 month old Blackstars and they're great birds. I came home tonight to close the pop door and do a head count and noticed one girl had feathers missing from around her neck and most of her tailfeathers were gone. She was pecking and pulling at her tail feathers and the area around her butt was bleeding. They'd been on the roost for about 2 hrs so I'm wondering if this is what a molt begins like or did something get to her and rough her up? I didn't see any signs of a scuffle and the rest of the girls were calm and roosting as normal. If this is a molt will the other chooks leave her alone or should I put her in quarantine?