The black swan (Cygnus atratus) is a large water bird of the Anatidae family, native to Australia. It is notable for its striking all-black plumage (except for the tips of its wings) and red beak, and belongs to the genus of swans along with other large species.

General characteristics

This swan measures approximately 110 to 140 cm in body length, with a wingspan of between 1.60 and 2.00 m. Its weight is usually between 3.7 and 9 kg. It has black plumage, except for the white flight feathers that can be seen when it flies. The beak is bright red with a white band near the tip. Males are slightly larger than females, although both display the same color pattern.

Feeding

It feeds mainly on aquatic plants, algae, and submerged or emergent vegetation, which it accesses thanks to its long neck. It also sometimes grazes on grasses near the water when aquatic food is scarce.

Behaviour

Black swans usually live in pairs, often for life, and defend their territory during the breeding season. Outside of breeding season, they may gather in large flocks, and even in flight they adopt V-shaped or linear formations. They also display courtship rituals such as the so-called “triumph ceremony” in which both members gesticulate and swim together.

Reproduction

The breeding season generally runs from February to September in Australia. The pair builds a large nest of reeds, grasses, and aquatic vegetation, either in shallow water or on the shore. Unlike other swans, black swans gather to nest in colonies. The female lays between 4 and 8 eggs (although this can vary), which both parents incubate for 35 to 48 days. The young swim almost immediately after hatching and can fly within a few months, although they remain with their parents until they mature.

Threats

Although the species is not seriously threatened, it may suffer from the loss of wetlands and alterations to its aquatic habitat, such as water pollution or a decline in aquatic vegetation.

Distribution

The black swan is native to southeastern and southwestern Australia, including Tasmania. It has also been introduced to New Zealand and parts of Europe, where there are feral populations. It lives in lakes, rivers, freshwater or brackish wetlands, as well as estuaries and shallow seas when food is available. It prefers areas with easily accessible aquatic vegetation.

Did you know? 

Unlike most swans, which have white plumage, this one is black except for the tips of its wings, which are only visible in flight.

Its long neck is very pronounced: among swans, it is one of the longest in proportion to its body.

In 18th-century European culture, the appearance of the black swan was so surprising that it gave rise to the use of the expression “black swan” to describe an unexpected event.

Conservation status

The International Union for Conservation of Nature (IUCN) classifies the black swan as Least Concern, given that it has a stable population and wide distribution.