'Heavy Ducks' are those which generally weigh over 7lbs in the female and 8lbs in the drake. The largest of the heavy breeds are the traditional English Aylesbury and the Rouen. Drakes can weigh up to 12 lbs and ducks 9-11 lbs.
In general, 'heavies' are the old-established breeds, which were developed for the table. The Cayuga was the table bird of the USA before the Chinese Pekin was imported in 1874. The Pekin revolutionised the table duck industry both in the USA and in the UK where it began to replace the pink-billed commercial Aylesbury.
The Muscovy duck (Cairina moschata) is also classified as a Heavy 'Duck'. It is, in fact, a different species from all the other breeds (which were all developed from the mallard). The Muscovy is indigenous to South America but rapidly spread worldwide after the discovery of the Indies by Columbus. It became known under several labels including Cairo, Barbary and Muscovy .
The Aylesbury (right): This is the British breed of heavy duck also designed, like the Rouen, for the table. It takes its name from the town of Aylesbury in the valley of the Thame, a tributary of the Thames. The white duck was reared there by the thousands in the 1700s and 1800s before a more intensive table duck industry was set set up using Pekin cross breeds. The original table Aylesbury did not have a deep keel. This became a feature of the exhibition strain in the late 1800s. Weights are the same as for the Rouen.
Blue Swedish: Blue ducks were known in Britain in the mid 1800s, but were probably more common in Europe where they were known as the Pommern and Swedish. Standardized in the USA in 1904, the Swedish was standardized in the UK only in 1982. Blue is an unstable colour in both ducks and Poultry. It is an 'impure' (heterozygous) form where the bird carries alleles for blue, not-blue and black. Such birds therefore produce, Blue Swedish, Black Swedish and pale blue Swedish. Blues cannot breed true to colour.
The Cayuga: Black ducks in good condition are arguably the most striking of the coloured breeds. In sunlight, exhibition specimens have a fantastic green sheen. Originating in the USA possibly as early as 1809, they took their name from Lake Cayuga in the 1850s.Drakes weigh 8lbs, and ducks 7lbs. Their eggs are greenish- black. As with all black birds (Black Runner and Black East Indian) the females tend to go white with age, but the drakes retain their colour.
The Pekin: The standard Pekin in the UK is the 'German' upright type, not the American flat, white duck which is probably an Aylesbury/Pekin cross, designed for the table. The plumage should have a yellow tinge - essential for exhibition. This colour is enhanced by a bird having recently grown new, oily feathers, or by diet.
Silver Appleyard ducks and drakes