Welcome to BYC.. and the answer is yes drakes have been known to even kill ducklings so it's always best to put mom and ducklings in a separate area until they are at least 3 weeks old big enough and fast enough to stay out of the drakes way. I make temp fencing with the plastic poultry fencing from Lowes it works great and that way everyone can still see each other and get use to the new lil ones.