I had to laugh when I read that. You won't get fertile eggs from that pairing. I don't know if it's normal, but I have a Muskovy drake that (until I clipped BOTH wings) kept flying the fence to fight with the roosters and try to breed with the hens. He wants nothing to do with the ducks, just the chickens. I tell everyone he has an identity crisis. Is he hurting the ducks or just being a pain?
Re-read my post and wanted to clarify--not laughing at you wondering about mixed chicks, laughing because you have a roo in love with ducks and I have a drake in love with chickens.
Thank you for replying so quickly! He's not hurting them... they just quack alot and try to run away. When he does jump on one they just sit down and look confused. The rooster is a Barred Rock and the ducks are Peking.