Latin: Nomonyx dominica
Average length: M 14", F 13"
Average weight: M 0.90 lbs, F 0.75 lbs.
Description: Masked ducks bear a close resemblance to the closely related ruddy duck, but they are smaller and in flight display a pronounced white speculum. Unlike the ruddy duck, the masked duck rises easily off the water when taking wing. Male masked ducks have an irregularly shaped black facial mask that covers its crown and cheeks and extends to a brilliant blue bill. A white spot is visible on the chin, but the remainder of the head, neck and chest are chestnut red. The back and sides are a similar shade, but are streaked and spotted with black. The lower chest and belly are white and the legs and feet are grayish or blackish-brown. The long wedge-shaped tail is composed of stiff black feathers. The male sometimes utters a loud "kiri-kuroo," often repeated when surprised. Female masked ducks resemble their counterpart in ruddy ducks. The principle difference is that masked ducks have two transverse bars of dark brown across buff-colored cheeks, one through the eye and one from the base of the bill to the back of the head. Ruddy duck females have a single transverse bar across the cheeks. The female has low hissing and clucking calls.
Breeding: In North America, masked ducks breed along the Gulf Coast of Texas. Female masked ducks are known to nest near water in rice fields and among rushes and lay an average of 4-6 buff-white eggs with granular shells.
Migrating and Wintering: Masked ducks are typically sedentary and the highest winter densities are found in southern Texas. However, masked ducks have been recorded in southern Florida and Louisiana.
Masked ducks are endemic to the Neotropical Realm. They are widely distributed but rather scarce in lowland Mexico, Central America, the Caribbean and tropical South America west of the Andes, south to northern Peru and east of the Andes, south to northern Argentina and Uruguay (Scott and Carbonell, 1986).
Population: The vast majority of suitable habitat for masked ducks in Texas is privately owned, making accurate population estimation difficult. Surveys conducted in 1992-'93 along the Gulf Coast of Texas suggest a maximum population of 3,817 birds.
Food habits: Masked ducks dive to feed on the seeds, stems, leaves and roots of aquatic plants; aquatic insects and small crustaceans.