Feather Loss Around Head

[MapleLeaf11]

One of my hens is loosing a lot of feathers at the back of her head. There is never any blood but she keeps loosing more everyday. I am suspecting that my rooster may be pulling them out but I haven't actually seen him doing it. Does anybody know any other things that could be causing this problem or how to stop the rooster?

 

[cutechick53]

Do you have any pictures you can post on here? When my friends rooster she put him in a separate pen and my other friend put a breeding saddle on the hen from the local feed store on her and that stopped the pecking.