Rouen Ducks are an attractive breed of waterfowl name of the French city where they originated. Rouens are similar in color to the wild Flying Mallard — male drakes have a lustrous green head and neck, a rich purplish brown chest, and steel gray penciling on the upper body, and female hens are mahogany brown with fine penciling of greenish black or brown. Some people refer to Rouens as Mallards but that is incorrect as Mallards fly will quite easily and Rouens do not. A Rouen weighs at least three times that of a Mallard. Mature male Rouens weigh about 7 pounds and females are about 5 pounds.