The black-necked swan is scientifically named Cygnus, meaning swan, and melancoryphus, meaning black pigment.
It is listed as the largest South American water-fowl. The black-necked swan is the least populated member of the Cygnus genus.
It breeds in the Chilean Southern Zone, Patagonia, Tierra del Fuego, and the Falkland Islands.
This species changes its location in the southern winter and moves up north towards Paraguay, Bolivia, and southern Brazil.
It is a short-winged bird, but that does little to its flight speed. It has an average lifespan of 10 years, though it can live up to 30 years.
A group of swans can be called a bevy, bank, herd, wedge, or flight.
Scientific Classification
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Aves |
| Order | Anseriformes |
| Family | Anatidae |
| Genus | Cygnus |
| Species | C. melancoryphus |
Description
The black-necked swan has white plumage, a black head, a black neck, and a grey bill with a red knob at the base.
These red knobs get larger in males during the breeding season. Behind the eyes, there are white stripes. The male swan is a bit bigger than the female.
Its young one has a light-greyish plumage with black feet and bill. It is somewhat quiet like its closest relatives, the mute and black swan.
However, one trait that stands them out from other wild water-fowls is that both the male and female swan often carry their offspring on their back.
The males are called cobs, while the females are called pens. The black-necked swan has up to 24 or 25 vertebrae, which are huge for a mammal as most mammals have just seven.
Among flight birds, the black-necked swan also has the largest size of eggs.
Habits
They are very social animals and very outgoing when it’s not their breeding period. The swans tend to get extremely territorial during their breeding period.
They split into mating pairs and take up nests in small groups or just as a pair.
They reunite once their eggs have hatched, each group numbering up to thousands of birds. They are likely to move around depending on the weather and resources available.
They are day creatures and spend most of their time on the water. The males defend their territory by displaying ferocious behavior, such as pushing their heads forward and bringing them down.
They fight with their wings, and when they are done, they return to the female in victory with a recurring chin lift and calling.
Black-necked swans that are raising their young ones can get very protective. They carry them on their back while swimming. Sometimes, the cobs violently vie for a mating partner.
They do this in something called a triumph ceremony. They challenge a rival suitor, and the winner returns to his prospective mate for an intricate ceremony. They are wary of humans and produce a soft, almost musical sound while flying.
Size
- Body length: 102 – 124 centimeters
- Weight: 4 – 5.4 kilograms
- Wing length: 135 – 177 centimeters
Habitat
They live in swamps, freshwater marshes, brackish lagoons, and shallow lakes in the southern region of South America.
The Great Chilean earthquake created wetlands like the Anwandter Nature Sanctuary in the Cruces River. These wetlands have become a popular spot for the black-necked swan.
Diet
The black-necked swans are herbivores. They primarily feed on aquatic vegetation, but they also feed on fish, eggs, and insects.
Their primary diet of aquatic plants plays a crucial role in their population control and prevents these plants from becoming invasive species.
Offsprings
The young ones of the black-necked swan are called cygnets or flappers. The swan attains sexual maturity two years after birth.
The pens (female swan) can lay up to 4-6 eggs at a time, and the incubation period lasts 34-36 days.
They give birth to their offspring on a nest bedded with vegetation. They attain independence when they reach the age bracket of 8 – 14 months.
The swans are monogamous in their mating, meaning they mate with one partner for life. Each pair of swans court each other by facing each other with shaking wings and nodding.
Conservation
In 2004 and 2005, black-necked swans from the Anwandter Nature Sanctuary died or moved away in their thousands. This was due to contamination by the Valdivia Pulp Mill situated on the Cruces River, which flows to the wetlands.
In 2005, nearly all the swans were killed, with just four birds left from a previous population of about 5,000. The cause of death was examined and discovered to be the high level of metallic content in the water, particularly iron.
Today, the swans are widely dispersed across various countries, and it is now a usual sight throughout the wetlands. The black-necked swan’s conservation status is pegged as Least Concern on the IUCN Red List of Threatened Species.
