I have five Pekin ducks that are siblings. They were hatched last summer sometime. I think they are all males, guessing by the curly tail feather. They are horrible to each other! All of a sudden with spring, they have started beating each other up. They all have bare necks and blood spots. They don't seem to pick on one particular duck, it seems like it is a free-for-all. Will they eventually stop doing this? I'm concerned they will seriously hurt one another. We call it the World Wrestling Federation duck style.