Assorted Crested Ducks are the hatchery's choice of the many breeds of crested ducks that AV Bird Hatchery hatches, which have not been sold as specific breeds of Crested Ducks. They are characterized by having crests that are globular in form, relatively but not excessively large in size. Since there is a lethal gene involved in producing crested ducks, special mating considerations must be made.