Both drakes are Crested ducks. The White Crested is pure Crested and the Multicolored is an Appleyard/White Crested Cross. Ducks are Blue and Black Swedish and pure White Cresteds. These should result in 50% Crested birds, some pure white and some with Mallard colors, depending upon the female. The young pair grew into the pure White Crested female and the Appleyard/Crested cross. These have been raised with chickens and Guinea hens with no issues.
This is a very old heritage breed. These are the ducks seen in the Dutch paintings of the 1700's.