One of my adult hens is being very aggressive with the new 8/9 week olds that moved to the coop today.
I think the general advice is to remove the aggressive one for a few days, and hopefully the dynamics of the pecking order will shift sufficiently that she will calm down when she returns.
So I moved Old Meanie to the garage today. But I'm wondering if anyone has actually been successful with having the hen behave better when she returns to the flock?
She is also broody, so maybe that makes her more aggressive than she normally would be?
Yes, and yes. Broodies can be very mean to flockmates, especially new ones, and removing her and letting them settle into a pecking order and then reintroducing her should change her status - except that if she is still broody she will still be testy. You might try putting her in a small area within the coop that is all her own until she is done being broody.