About Fulica leucoptera Vieillot, 1817
The white-winged coot (Fulica leucoptera Vieillot, 1817) measures 35 to 43 cm (14 to 17 in) in length and weighs approximately 400 to 600 g (14 to 21 oz). The sexes have identical outward appearance. Adults have a yellow to greenish yellow bill and a small yellow to orange-yellow frontal shield, though these colors can vary further. Their legs and feet are pale sea green to yellow-green, with blackish toes and joints. Their plumage is slaty gray, and is darker (blacker) on the head and neck. They have white undertail coverts, and wide white tips on their secondaries give the species its English common name. Immature birds have a dusky olive bill, greenish gray legs and feet, gray-brown upperparts, and paler underparts compared to adults. Juveniles are dark drab gray, with dusky mottling on a white head and neck. The white-winged coot is distributed across most of southern South America: it occurs in northern to central Chile, and in a separate range from eastern and southern Bolivia, Paraguay, and far southeastern Brazil, extending south through Uruguay and Argentina to Tierra del Fuego. There is also an established population in the Falkland Islands, and the species has been recorded as a vagrant in Peru. It lives in freshwater lagoons, ponds, marshes, and river backwaters, and prefers those habitats with grassy or bare shores and large amounts of submerged plants or floating duckweed. It may sometimes be found on near-shore saltwater.
