I have two peking ducks, 1 male and 1 female that are living with my 30 hens and 2 roosters. All of a sudden they have become very territorial and chasing my hens around the yard. Today I caught the male holding the hen down ripping at her head, while the female was pecking at her. It almost looked as if he was trying to breed her. I don't know what to do about this. They are my children's ducks, but I can't have them hurting the chicken's. Any advice would be helpful. I see roasted duck in my future....