I have an agressive hen (RIR) that appears to mount 2 out of 3 new hens (Ameracuanas) that I introduced to the flock 6 weeks ago. I have noticed the bare back area on the 2 hens. I do not have any roosters. I have only witnessed it twice. Is my alpha hen just being agressive? How do I stop it. The run is plenty big enough for them all to get along.