Hen became an overnight bully

[Tessaandherchickens]

I have a case of bullying but it seems abnormal.

My hen Millie has been the bottom of the pecking order her whole life and is very submissive. We added five pullets this summer and she was mean to them, but I finally got them integrated and everything was fine.

Yesterday out of nowhere we saw Millie chasing one of the top hens (omelette) and she’s been doing it ever since. Pretty vicious attacks, but no blood yet. It’s only directed at this one chicken, she’s still submissive to all of the other old flock mates. It’s gotten to the point where Omelette stays in the coop cowering all day and I’m at my wits end. The process of them roosting at night is frustrating because Millie gets pecked on by the other older hens, but she also viciously attacks this omelette, and Omelette will peck on the others. So it’s very dramatic at bed time and I feel I have to protect the omelette from injury.

Any ideas why she would suddenly have it out for one chicken? I’m going to isolate Millie in a small fenced area tomorrow, but is there anything else I can do?

I have 10 chickens in a run that’s about 850 square feet, so I don’t think it’s a space issue?

 

[Loving my girls]

You mention the run size but how big is the coop ?

 

[LaFleche]

Could you provide a picture of your set-up? Adding some clutter will help to break the line of view and allow attacked birds to get away.

Molting season and broodiness will mess with the usual hierarchy and otherwise subordinate birds might see a chance for climbing up the ladder for a better position when they perceive a weakness in a higher ranking bird.

You can remove the aggressor out of sight from your flock for a few days/a week which will help to cool her off and give the attacked bird some relief.
Pinless peepers might also help and she could remain with the flock while wearing them.