Patagonian crested duck
Encyclopedia
The Patagonian Crested Duck (Lophonetta specularioides specularioides), also known as the Southern Crested Duck, or the Grey Duck in the Falkland Islands, is the nominate of two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 of the Crested Duck
Crested Duck
The Crested Duck is a species of duck native to South America, the only member of the monotypic genus Lophonetta. It is sometimes included in Anas, but it belongs to a South American clade that diverged early in dabbling duck evolution . There are two subspecies: L...

.

Description

The duck has a grey chin, neck and face, with the body plumage a mixture of brown and grey feathers giving a mottled look. Its eyes are red with black pupil
Pupil
The pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. It appears black because most of the light entering the pupil is absorbed by the tissues inside the eye. In humans the pupil is round, but other species, such as some cats, have slit pupils. In...

s. The crown and the feather
Feather
Feathers are one of the epidermal growths that form the distinctive outer covering, or plumage, on birds and some non-avian theropod dinosaurs. They are considered the most complex integumentary structures found in vertebrates, and indeed a premier example of a complex evolutionary novelty. They...

s surrounding the eyes are dark brown or blackish. The tail feathers are also dark, sometimes black. It has a black beak
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...

 and dark grey to black legs and webbed feet. It moults twice a year and also has an annual wing feather moult. It is a medium-sized duck around 50–60 cm in length. Females and males weigh about 1 kg though usually the males are slightly larger. It is very similar to the other subspecies, the Andean Crested Duck
Andean Crested Duck
The Andean Crested Duck is one of two subspecies of the Crested Duck. It is much rarer than its sibling subspecies, the Patagonian Crested Duck.-Description:...

, differing in being slightly smaller, with more distinctively mottled underparts, and a lighter purple speculum
Speculum feathers
The speculum is a patch, often distinctly coloured, on the inner remiges of some birds.Examples of the colour of the speculum in a number of ducks are:* Common Teal and Green-winged Teal: Iridescent green edged with buff....

 with green or bronze reflections.

Young ducks have smaller crests than the adults, or lack crests entirely. The faces of the young birds are browner than those of the adults; the abdomen is also much whiter and the mandible a pinkish colour.

Distribution and habitat

The duck occurs in southern South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

, where it is found in Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

, Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 and the Falkland Islands
Falkland Islands
The Falkland Islands are an archipelago in the South Atlantic Ocean, located about from the coast of mainland South America. The archipelago consists of East Falkland, West Falkland and 776 lesser islands. The capital, Stanley, is on East Falkland...

. It may be found by the coast or in freshwater. It lives in marshland, swamps, lakes and pools, or in sheltered bays on the coast. It is non-migratory; in winter it finds a sheltered place to stay during the colder months. For high altitude and high latitude birds this usually involves dispersing along the South American coast.

Breeding

The reproductive season of the duck varies according to geographical location. In the Andes it is mainly between January and March, whereas in more southern areas it tends to be later, between October and December. Preferred nesting habitat is on the ground in tall grass or shrubbery on small islets or lake shores, but occasionally further away from water. The nest is built by a solitary pair and is made up of vegetation and lined with their soft breast feathers.

A clutch of eggs is made up of between five and eight cream-coloured eggs, which weigh about 56 g and are 63 x 43 mm in size. A double brood is quite common. Incubation is undertaken by the female, and takes about 30 days, following which the eggs hatch synchronously. Once hatched both parents tend to the ducklings. They fledge at about 10–11 weeks old.

Feeding

The duck eats aquatic invertebrates such as insects and their larvae, crustaceans and molluscs. It also eats small amounts of aquatic plants such as the filamentous algae common in many ponds. The diet for the young is much the same as their parents. To get their food the ducks dive for algae and invertebrates at the bottom of waterbodies. Diet varies between fresh and salt water habitats, as well as seasonally.

Status and conservation

The Patagonian Crested Duck is not endangered. Although its global population is unknown, there are thought to be around 10,000 breeding pairs in the Falkland Islands. Its sibling subspecies, the Andean Crested Duck, is extremely rare even in captive collections.

Predators

One of the main predators of the Patagonian Crested Duck is the Black-crowned Night Heron
Black-crowned Night Heron
The Black-crowned Night Heron commonly abbreviated to just Night Heron in Eurasia, is a medium-sized heron found throughout a large part of the world, except in the coldest regions and Australasia .-Description:Adults are...

. Adult ducks have few other predators though the younger ducklings are subject to predation by Brown Skua
Brown Skua
The Brown Skua , also known as the Antarctic Skua, Southern Great Skua, Southern Skua, or Hākoakoa , is a large seabird that breeds in the subantarctic and Antarctic zones and moves further north when not breeding...

s.

External links

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