Hello, Bunny, and welcome to BYC! I'm so glad you decided to join our friendly and helpful community 
Do you know what gender your ducklings are? I don't know what your housing situation is like but I wanted to tip you off to the fact that unless they're both girls they shouldn't be housed with chickens. Male ducks often attempt to mate with chickens if they have the opportunity and their anatomy is not compatible. Your chickens will get injured at best and killed at worst.

Do you know what gender your ducklings are? I don't know what your housing situation is like but I wanted to tip you off to the fact that unless they're both girls they shouldn't be housed with chickens. Male ducks often attempt to mate with chickens if they have the opportunity and their anatomy is not compatible. Your chickens will get injured at best and killed at worst.