I have a 4 month old rooster (Bielefelder) sharing a coop with 5 pullets. 3 of the pullets are 4 months old and 2 are three months old. They are sharing a 30x30 run with a bantam (cochin) rooster and his 4 hens. The Bielefelder is 3x the size of the cochin. Until now, I have only ever had one rooster in each pen. I combined the two groups two weeks ago. There has been a little chasing but mostly they ignore each other. The young rooster is trying to mate with the pullets. He is grabbing the back of their heads but is not mounting them. He is usually standing in front of them when he does this. They scream and try to run. He eventually lets go of their head. I have not kept alot of roosters but I have kept some and I have never seen this before. It has been going on for almost a week. Could this have anything to do with sharing the run with another rooster. So far he is not people aggressive at all so I was hoping to keep him.