Seriously valid concerns. When I acquired my first four runner ducklings -- before my breeder learned to sex the babies -- I ended up with three males and one female.
I had two concerns. First, that the males would fight each other over the girls. Maybe because they grew up together, that didn't happen.
Second, that the single hen would be way over-romanced. By the time I realized Quinn was the only girl, I was able to purchase ONE semi-grown hen to take the pressure off. Strangely, the group seemed to accept Quinn as the leader, and she wasn't overly bred. Paige, on the other hand, was the apple of every drake's eye.
Short of separately housing them or watching every second that they're free, my only course of action was to get more females. Even then, there was frequently bleeding from the backs of their heads.
I hope you find a way to keep your boys. Two years ago, when my breeder accidentally sold me a male duckling in the group, she offered to take Lane back. By then, I didn't want to give him up. So, I applied chicken math to my duck problem -- and bought more girls!
I’ll post a pic of my duckies!
