Help! Chicken picking on who flock

[OhioTanya]

Help! Chicken picking on WHOLE flock.

I have 6 pullets I raised this spring together. They are a mixed breed bunch. 2 ISA Browns, 2 Wyandots, 1 Brahama, and 1 Rhode Island Red.
I noticed that all the chickens except for one had feathers plucked from her back. Some of them have feAthers pluked from their necks too. ONE of the Wyandotte's looks great and has NO feathers missing. I watched the flock closer and watched that one chicken peck ALL the other chickens at random times for no apparent reason. These chickens were raised together. They have been in their outside coup all summer. I don't know how long she has been doing this, but I noticed whole feathers in the coup a LOT. I thought it was odd because I had never had that with my other chickens. I have been raising chickens for four years now. I started fresh this year with all new pullets.
So what should I do? What are my options? Should I slaughter her?

 

[QueenMisha]

You could try separating her then reintroducing or applying pinless peepers... but to me she definitely sounds aggressive enough to warrant a place on the dinner table.

 

[OhioTanya]

What is pinless peepers?

 

[QueenMisha]

What is pinless peepers?

They are an anti-picking device that are commonly used in very cannibalistic species such as pheasants. They look a lot like opaque chicken sunglasses; they essentially provide the same effect that blinders do on horses. They prevent the bird from seeing directly forward, which does a lot to inhibit its ability to pick and attack other birds. They attach by two spokes that rest in the nostrils. I've had great success with them in my pickiest birds and my guineas.