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Biologická data

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The Black Swan (Cygnus atratus) is a large waterbird, a species of swan, which breeds mainly in the southeast and southwest regions of Australia. With a body length of up to 142 cm and a wingspan reaching over 2 meters, it is one of the largest waterfowl in the world. The Black Swan is distinguished by its mostly black plumage, which contrasts strikingly with its bright red bill, tipped with a white band. Its eyes are deep brown, and juveniles can be differentiated by their greyer plumage and paler bills.

Black Swans are unique not only in color but also in their aquatic behaviors. They are excellent swimmers and are almost exclusively found in wetlands, including lakes, rivers, and sometimes even the open sea, as long as there is a nearby freshwater source for drinking. These birds are also capable flyers, although they are more often seen gliding majestically across water surfaces than in the air.

The diet of the Black Swan is primarily vegetarian. They feed on a variety of aquatic and marshland plants, both submerged and emergent. Their long necks serve them well in foraging for food underwater. In deeper water, they upend, similar to ducks, to reach vegetation below the surface. On land, they will also graze on grasses and crops, which sometimes brings them into conflict with farmers.

Social creatures, Black Swans are often found in large flocks, which can number in the thousands in areas rich in food and habitat. They are highly territorial during the breeding season, which can occur any time after significant rainfall events. Their nests are large mounds of reeds, grasses, and weeds, built at the water’s edge. A typical clutch contains 4 to 8 greenish-white eggs, which are incubated by both parents for about 35 to 40 days.

One of the most fascinating aspects of Black Swan behavior is their monogamous pairing, which often lasts for many years and, in some cases, for life. Interestingly, a significant portion of pairs are homosexual, particularly among males. These pairs will sometimes mate with a female only to obtain eggs, after which they drive the female away and raise the offspring themselves.

Cultural significance surrounds the Black Swan in its native Australia and beyond. It is the state bird of Western Australia and appears in the flags and heraldry of several Australian states. The term "black swan" has also entered the lexicon as a metaphor for an unexpected or unforeseeable event, especially one of large magnitude, inspired by the European discovery of Black Swans in Australia, an event that overturned the old presumption that all swans were white.

In conclusion, the Black Swan is a captivating species, not only for its striking appearance but also for its unique behaviors and the cultural symbolism it carries. Its adaptability to both natural and modified landscapes has allowed it to thrive in many areas, although it remains a protected species to ensure its continued survival in the wild.