Tail Feathers shredded on hen (with photo) Any ideas?

[brianl0646]

One of my chicken's tail feathers are messed up for lack of a better term. Looks like something has been chewing on them. I have 4 hens, they never peck at each other or fight. I do see Amelia (The hen with the bad feathers) scratch at herself, but I have never witnessed her pulling out feathers. She is a year old, seems perfectly healthy otherwise. Any ideas?

Brian

 

[emys]

Looks like another hen was picking at her.

 

[luvchicks8]

Might what to check for lice or mites