get VETERICYN and isolate the hurt ones until they are fully healed. No matter how this or what happened, this will prevent any more damage.
they are pecking each other due to girls losing feathers. If there are any differences with any of them, the group focuses on that. We had horribly severe spots that began as dime sizes then got to cover entire back-under tail feathers.
Post a pic if you can. That doesn't sound like rooster damage to me.
So this is one of my girls. You can see a little feather damage on the middle of her back just before her tail.
This picture shows when you lift her wing. Looks fairly normal.
Now close up and under the feathers. They are like scrapes. Not very deep or bloody. She did have one that is more scratch like. Most seem to be abrasions. It's enough to scab up and it can't be comfortable.
Lots of broken feathers and several of these small scabbed spots. I did get more fabric today for saddles. I have vetericyn but they seem to heal pretty quick on their own. I hate that it's happening.