I have 12 hens that are 3 years old and 2 hens and a rooster that are 18 months old. The younger hens and rooster were hatched by one of the 3 year old hens last year. The rooster is nice to the hens and has not offered to attack me, he is pretty laid back. I let the flock free range when we are home. About a month ago my speckled sussex hen started hanging around the back porch-far from the coop and her neck feathers were a bit ruffled and I noticed she appeared to be afraid of the rooster. She is the very last to go into the coop at night. DH and I were gone for two days and when I got home I went to check the hens. The speckled sussex was in the coop hiding behind my one broody hen. I moved the broody hen and her to collect eggs. When she went out the rooster began to mercilessly chase her, pin her to the ground and pull out her neck feathers. He made no attempt to breed her. These two have been together their entire life and I have never seen the rooster act this way. What the heck is causing this change? I put the speckled sussex and the broody hen in there own run for now. Thanks for any help.