[order] ANSERIFORMES | [family] Anatidae | [latin] Oxyura ferruginea | [authority] Eyton, 1838 | [UK] Andean Duck | [FR] Erismature des Andes | [DE] Peruan. Schwarzkopfruderente | [ES] Pato Andino | [NL] Rosse stekelstaarteend
||Colombia to Southern Cone
The stiff-tailed ducks are part of the Oxyurinae subfamily of ducks. All have, as their name implies, long stiff tail feathers, which are erected when the bird is at rest. All have relatively large swollen bills. These are freshwater diving ducks. Their legs are set far back, making them awkward on land, so they rarely leave the water. Their unusual displays involve drumming noises from inflatable throat-sacs, head throwing, and erecting short crests. Plumage sequences are complicated, and aging difficult. Plumage is vital for survival because of this animals tendency to spend time in the water. Without plumage this duck would die of hypothermia because of an inability to regulate its body temperature. A fossil species from the Late Pliocene or Early Pleistocene of Jalisco (Mexico) was described as Oxyura zapatanima. It resembled a small Ruddy Duck or, even more, Argentine Blue-bill. A larger Middle Pleistocene fossil form from the southwestern USA was described as Oxyura bessomi; it was probably quite close to the Ruddy Duck.
The male is chestnut with a black head and a bright blue bill which has a slight bump over the nostril. It usually holds its tail cocked. Adult males have a rust-red body, a blue bill, and an all blackface with with black cap. Adult females have a grey-brown body with a greyish face with a darker bill, cap and a cheek stripe.
Listen to the sound of Andean Duck
Copyright remark: Most sounds derived from xeno-canto
recorded by Andrew Spencer
South America : Colombia to Southern Cone
Freshwater swamps, lakes, pools, and marshes with emergent vegetation and open water are preferred breeding habitats, although outside the breeding season the species can also be found on larger lakes, brackish lagoons and estuaries
Unlike most waterfowl, pairs form on the breeding grounds. Males perform unique, comical courtship displays and establish seasonally monogamous pair bonds, but some males are polygynous. Females lay large, rough, white eggs in well-concealed nests over water; their eggs are the largest relative to body size of all waterfowl, with a correspondingly high energetic cost of egg production. Highly precocial ducklings are tended by the female only and for a shorter period of time than most ducks. Some non-paternal males are known to accompany the brood but provide no care. Unusual among waterfowl, except other stiff-tailed ducks, a small percentage of Andean Ducks apparently undergo 2 remigial molts per year. Based on its strong relation with the Ruddy duck we estimate the incubation period to just under a month; fledging period 7-9 weeks with a clutch size of 5-15 eggs.
These birds dive and swim underwater. They mainly eat seeds and roots of aquatic plants, aquatic insects and crustaceans.
copyright: Josep del Hoyo
Not recognized by the Birdlife taxonomic workgroup. There is considerable debate about the taxonomy of this species with many authorities considering it to be a sub-species of Ruddy Duck Oxyura jamaicensis which is found in North America and the Caribbean as well as in South America. Others treat the South American sub-species O. j. andina and O. j. ferruginea as a separate species
Race ferruginea often considered a full species; race andina, intermediate between jamaicensis and ferruginea, might be of hybrid origin. Population of North America has been assigned separate subspecies rubida, though doubtfully valid.
Sedentary with some small movements observed.