My chickens are all young - the Head Hen is only 10 wks old. The EE rooster is 8 wks old. He has started chasing Rebecca (who is the oldest of the 8 in my flock) and will grab her neck feathers to try to mount her. He doesn't even have a fully-developed crow, yet! (Just a two-syllable, two-toned braying sound.) He is NOT interested in doing the same to the other pullets. He'll stop in front of 'em and posture, but they all stand up tall right back at him. Rebecca is the only recipient of his harassing behavior. And she doesn't like it at all. She's become less of the Head Hen since it started, which makes me sad. She used to boss him around, now she tries to stay away from him. Since all the chickens cluster together much of the time, she tends to go 'round the other side of the coop to be alone. None of them will be old enough to lay eggs until the beginning of March. I like my little baby rooster - at least I did until he started bothering Rebecca.