Hi all, I have a small flock of three barred rock hens that I've raised together from day-old chicks; they are currently just over a year old. Recently, within the last couple of weeks, the head hen, Bernadette, began harassing Amy to the point of mounting her, pinning her down, and pecking/pulling feathers out of her head, drawing blood and causing injury (she was leaving the third hen, Penny, alone as far as I was able to observe). There was no provocation as far as I could tell; it didn't seem to have anything to do with food, water, or nesting boxes and generally occurred in the run (as opposed to in the coop/free ranging).
I tended Amy's injuries and applied Pick No More lotion, and then separated Bernadette from the other two within the coop and run (they could still see and hear each other but could not access each other) for approximately a week. When I reintegrated, Bernadette then went after both Amy AND Penny with the same aggression as before and at this point, Amy was absolutely terrified any time Bernadette was even anywhere near her, whether she was charging her or not.
My next step was to completely isolate Bernadette from her flock mates by placing her in a dog crate in the garage; totally out of sight and earshot of Amy and Penny. While Bernadette was isolated, Amy and Penny functioned as they normally do when there's peace in the coop (as there had been up to two weeks ago); dust bathing together, foraging together, and generally enjoying each other's company, peacefully. There was no aggression between the two of them. When I reintegrated Bernadette for the second time after three days of solitary isolation, there was no change to her behavior whatsoever and she began harassing her flock mates within hours of being reintegrated.
There has been no change to the structure of the flock (no new birds have been introduced) and there are no other obvious stressors within the group (plenty of coop/run space and free range time, access to fresh food and clean water, indoor and outdoor roosts, tree trunks, hanging treat baskets, more than enough nesting boxes to go around, etc.). Bernadette has been head hen from day one but has only recently became aggressive to the point of causing injury/drawing blood.
Also of note, this morning, Bernadette sounded like she was attempting to crow at 5:30am...I've read of hens taking on rooster tendencies so I'm inclined to think that's what's going on here. I don't believe she has a hormone imbalance as she's been laying faithfully during all of this (even while she was in the dog crate) and her eggs are perfect.
At this point, I've arranged to rehome her with my in-laws as they have property and other farm animals (but no chickens); any other options I might not have considered (I'm not prepared to process any of my birds right now so that's out of the question)?
I don't believe this is normal pecking order behavior and believe it to be bullying but would love your insights/suggestions. Thank you!
Edited by FunOnABun - 5/19/16 at 10:51am