The domesticated Muscovy duck

(Cairina moschata forma domestica )

Unlike other domestic ducks, the Muscovy did not originate from the Mallard. Muscovy ducks originated from wild Muscovys which are native to Central and South America and Mexico. There a are a few feral populations established in the USA.

The Muscovy duck has been bred since pre=columbian times by Native Americans.

The domestic Muscovy is much heavier than it's wild counterpart. Muscovy drakes can reach a weight around 15lbs. The hens are much smaller reaching a weight around 6.6lbs. The males do not have the flying capapbilities of their wild counterpart, due to their weight. The hens, however, can fly and are often found on the roof of the barn if their wings are not clipped. 

Muscovys do not mate for life like the Mallard and can breed up to 3 times a year. They are natural setters and very capapble mothers.

Muscovy ducks are a very popular table fare. They also make excellent insect control and pets. They will aslo eat, amphibians, small fish, reptiles and like to graze pasture and water plants. 

Reference: Muscovy Duck: Wikipedia