I have a BO roo and RIR hen. They're each about 20 weeks old. The other breeds I want are (mostly) bantams. I especially want D'uccle hens. If he has only 4 full sized hens, might he hurt the little girls? If I free range the smaller ones (part time) in another part of the yard, will the 4 ft fence stop him or will the temptation make him fly over?