I have two cockerels and 6 pullets. Two of the pullets are 16 wks old and the rest 18. I have recently noticed one of the cockerels chasing some of the pullets. He grabs them on the back of their neck and it looks like he is trying to mount them. He did mature fast and was crowing at 8 wks. Can he injure the pullets if they are not fully grown? Thanks for the info