We have some breeding pens set up and I can't remember seeing any of them doing any breeding while their in them. When I let them out its the first thing the roo wants to do. Are there some hard and fast rules for this or what am I missing? Each coop is 4'x5' and has an attached run that is 5'x16'. The most any pen has in it is 8 birds. I also built a couple hoop coops that are 8'x8' and they too will immediately get busy when their let out.