Flying Steamer Duck

This is a robust and heavily built waterfowl species, notable for being the only member of its genus that retains the functional ability for sustained flight, although its take-off requires a significant running start on the water surface. Its total length ranges from 66 to 71 centimeters, with adult males weighing between 2.4 and 3.1 kilograms and females being slightly lighter at 2.1 to 2.8 kilograms. The upperparts and flanks are covered in grayish-brown plumage, while the underparts present a clean white coloration. A distinctive white wing speculum is highly visible during flight and when the wings are folded. Sexual dimorphism is clearly expressed in head and bill color: breeding males exhibit a pale gray to whitish head contrasted with a bright orange-yellow bill, whereas females and non-breeding males possess darker gray heads and duller greenish-yellow or dusky bills.

Geographical distribution: It is native to the southern tip of South America, with its range encompassing portions of Chile and Argentina, as well as the Falkland Islands. In Chile, its distribution spans from the Los Lagos Region southward to Cape Horn. In Argentina, it is found from the provinces of Neuquén and Río Negro down through the mainland and coastal areas of Tierra del Fuego.

Habitat: Unlike other species in its genus which are strictly marine, this bird exhibits a broader ecological adaptability, utilizing both marine coastal environments and freshwater bodies. It frequently occupies rocky coastlines, sheltered bays, channels, and river mouths, but also establishes permanent populations in inland freshwater lakes, Andean lagoons, and fast-flowing rivers within the Patagonian forests and steppes.

Feeding: The diet is predominantly carnivorous, consisting mainly of benthic aquatic invertebrates. In marine environments, it actively dives to forage on bivalves, gastropods, and various crustaceans such as crabs and amphipods. In freshwater habitats, its prey selection shifts toward aquatic insect larvae and small fish. It acquires food through plunge-diving, propelled by its strong, webbed feet to reach underwater substrates.

Behavior: It is renowned for its highly aggressive and territorial nature, fiercely defending its feeding and breeding zones against conspecifics and other waterbird species. Although capable of flight, it frequently resorts to running across the water´s surface while vigorously flapping its wings, a characteristic behavior known as "steaming" which creates a prominent wake. During the post-breeding season, it undergoes a complete molt, temporarily losing its ability to fly and forming moderate-sized molting flocks in secluded coastal areas.

Nesting: The breeding season takes place between October and January. The nest is built on the ground, carefully concealed within dense shrubs, tall grasses, or rocky crevices near the water´s edge. The nest structure is a shallow depression lined with twigs, grass, and a thick layer of pectoral down plucked by the female. A typical clutch consists of 5 to 9 cream-colored eggs. Incubation is performed solely by the female and lasts for approximately 30 to 40 days, while the male maintains a constant vigil nearby, serving as a highly defensive territorial sentinel.

Conservation status: It is currently classified as Least Concern (LC) on the IUCN Red List of Threatened Species. Although global populations appear to be stable, localized threats persist, including predation on eggs and chicks by introduced species such as the American mink (Neovison vison), marine pollution from oil spills, and the degradation of inland freshwater bodies due to anthropogenic development and tourism.