Black-necked Swan
Encyclopedia
The Black-necked Swan is the largest waterfowl
native to South America
. Males are 115 to 140 cm (45.3 to 55.1 in) and weigh 4.5-6.7 kg (10-14.8 lbs); females are 100 to 124 cm (39.4 to 48.8 in) and weigh 3.5-4.4 kg (7.7–9.7 lbs). The wingspan ranges from 135 to 177 cm (53.1 to 69.7 in). The body plumage is white with a black neck, head and greyish bill
. It has a red knob near the base of the bill and white stripe behind eye. The sexes are similar, with the female slightly smaller. The cygnet has a light grey plumage with black bill and feet. The Black-necked Swan was formerly placed in monotypic
genus, Sthenelides.
The smallest member in its genus, it is found in freshwater marshes, lagoon
and lake
shores in southern South America
. The Black-necked Swan breeds in Chilean Southern Zone
, Patagonia
, Tierra del Fuego
and on the Falkland Islands
. In the austral winter, this species migrates
northwards to Paraguay
and southern Brazil
. The wetlands created by the Great Chilean Earthquake
like Carlos Anwandter Nature Sanctuary
in Cruces River
have become important population centers for the Black-necked Swan.
In 2004 and 2005 thousands of Black-necked Swans in the Carlos Anwandter Nature Sanctuary in Chile
died or migrated away following major contamination by Valdivia Pulp Mill
located on the Cruces River
which feeds the wetlands. By August 2005 the birds in the Sanctuary had been "wiped out"; only four birds could be observed from a population formerly estimated at 5,000 birds. Autopsies on dead swans attributed the deaths to high levels of iron and other metals polluting the water.
The Black-necked Swan, like its nearest relatives the Black
and Mute Swan
is relatively silent. Also, unlike most wildfowl, both parents regularly carry the cygnets on their backs. The female lays four to six eggs in a nest of vegetation mound. The diet consists mainly of vegetation, insects and fish spawn.
Widespread and common throughout its habitat, the Black-necked Swan is evaluated as Least Concern on the IUCN Red List
of Threatened Species. It is listed on Appendix II of CITES.
Waterfowl
Waterfowl are certain wildfowl of the order Anseriformes, especially members of the family Anatidae, which includes ducks, geese, and swans....
native to 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...
. Males are 115 to 140 cm (45.3 to 55.1 in) and weigh 4.5-6.7 kg (10-14.8 lbs); females are 100 to 124 cm (39.4 to 48.8 in) and weigh 3.5-4.4 kg (7.7–9.7 lbs). The wingspan ranges from 135 to 177 cm (53.1 to 69.7 in). The body plumage is white with a black neck, head and greyish bill
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...
. It has a red knob near the base of the bill and white stripe behind eye. The sexes are similar, with the female slightly smaller. The cygnet has a light grey plumage with black bill and feet. The Black-necked Swan was formerly placed in monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
genus, Sthenelides.
The smallest member in its genus, it is found in freshwater marshes, lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
and lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
shores 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...
. The Black-necked Swan breeds in Chilean Southern Zone
Zona Sur
The Zona Sur is one of the five natural regions on which CORFO divided continental Chile in 1950. Its northern border is formed by the Bío-Bío River, the limit with the Central Chile Zone. By west with the Pacific Ocean, by the east with the Andean mountains and Argentina. Its southern border is...
, Patagonia
Patagonia
Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...
, Tierra del Fuego
Tierra del Fuego
Tierra del Fuego is an archipelago off the southernmost tip of the South American mainland, across the Strait of Magellan. The archipelago consists of a main island Isla Grande de Tierra del Fuego divided between Chile and Argentina with an area of , and a group of smaller islands including Cape...
and on 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...
. In the austral winter, this species migrates
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
northwards to Paraguay
Paraguay
Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the...
and southern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. The wetlands created by the Great Chilean Earthquake
Great Chilean Earthquake
The 1960 Valdivia earthquake or Great Chilean Earthquake of Sunday, 22 May 1960 is to date the most powerful earthquake ever recorded on Earth, rating 9.5 on the moment magnitude scale...
like Carlos Anwandter Nature Sanctuary
Carlos Anwandter Nature Sanctuary
Carlos Anwandter Nature Sanctuary is protected wetland in Cruces River about north of Valdivia, Chile. The sanctuary is named after the German politician Carlos Anwandter who settled in Valdivia during the 1850s...
in Cruces River
Cruces River
The Cruces River is a river near Valdivia, Chile. Río Cruces originates from hills near the Villarica volcano and flows then in south-west direction. The southern and final part of the river follows the Valdivian Coastal Range. At the latitude of Valdivia it is crossed by Río Cruces Bridge near...
have become important population centers for the Black-necked Swan.
In 2004 and 2005 thousands of Black-necked Swans in the Carlos Anwandter Nature Sanctuary 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...
died or migrated away following major contamination by Valdivia Pulp Mill
Valdivia Pulp Mill
The Valdivia Pulp Mill or Planta Valdivia is a pulp mill and biomass-fueled electrical generating station in San José de la Mariquina, Los Ríos Region, Chile. Although the main activity is wood pulp production it generates 61 MW of electricity from the burning of volatiles and black liquor...
located on the Cruces River
Cruces River
The Cruces River is a river near Valdivia, Chile. Río Cruces originates from hills near the Villarica volcano and flows then in south-west direction. The southern and final part of the river follows the Valdivian Coastal Range. At the latitude of Valdivia it is crossed by Río Cruces Bridge near...
which feeds the wetlands. By August 2005 the birds in the Sanctuary had been "wiped out"; only four birds could be observed from a population formerly estimated at 5,000 birds. Autopsies on dead swans attributed the deaths to high levels of iron and other metals polluting the water.
The Black-necked Swan, like its nearest relatives the Black
Black Swan
The Black Swan is a large waterbird, a species of swan, which breeds mainly in the southeast and southwest regions of Australia. The species was hunted to extinction in New Zealand, but later reintroduced. Within Australia they are nomadic, with erratic migration patterns dependent upon climatic...
and Mute Swan
Mute Swan
The Mute Swan is a species of swan, and thus a member of the duck, goose and swan family Anatidae. It is native to much of Europe and Asia, and the far north of Africa. It is also an introduced species in North America, Australasia and southern Africa. The name 'mute' derives from it being less...
is relatively silent. Also, unlike most wildfowl, both parents regularly carry the cygnets on their backs. The female lays four to six eggs in a nest of vegetation mound. The diet consists mainly of vegetation, insects and fish spawn.
Widespread and common throughout its habitat, the Black-necked Swan is evaluated as Least Concern on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
of Threatened Species. It is listed on Appendix II of CITES.
Further reading
Database entry includes justification for why this species is of least concern- David, N. & Gosselin, M. (2002): Gender agreement of avian species names. Bull. B. O. C.Bulletin of the British Ornithologists' ClubThe Bulletin of the British Ornithologists' Club is an ornithological journal published by the British Ornithologists' Club . It is cited as Bull. B. O. C.Many descriptions of birds new to science have been published in the bulletin....
122: 14-49.
External links
- BirdLife Species Factsheet
- IUCN Red List
- Black-necked Swan videos on the Internet Bird Collection
- Stamps (for ArgentinaArgentinaArgentina , 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...
, BrazilBrazilBrazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, ChileChileChile ,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...
, Falkland IslandsFalkland IslandsThe 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...
, UruguayUruguayUruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...
) with RangeMap - Black-necked Swan photo gallery VIREO