Males have a green head and neck, with a purplish brown chest, and grey mottling elsewhere. Females have brownish feathers, with some green mottling.
By 12 to 15 weeks, the birds will weigh 6 to 8 pounds (2.7 to 3.6 kg.) Males will grow up to 7.7 pounds (3.5 kg); females up to 6.6 pounds (3 kg.)
A female will lay 35 to 125 eggs a year. The eggs weigh about 80g, or a little more, and have a greenish shell.
The birds are raised chiefly for meat and are good for roast duck.
The Dark Rouen Duck was developed by English breeders from the clear Rouen duck. They made it larger, and plumper, and improved the colour.
The breed was introduced into America in 1850 by D. W. Lincoln of Worcester, Massachusetts, and in 1874, included in the American Poultry Association’s Standard of Perfection.