pigeon eating hens

[Aquaponics in Paradise]

So today I found the remains of a pigeon, making this the 4th pair of wings inside my chicken tractor. Is this normal?
Usually I'll find only the wings and the connecting tissue between the wings, but today i found the wings and most of the head

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[tammyd57]

I wish my chickens would eat the pigeons that keep stealing their food. They do like to eat gophers though.