page_title: Swan
section_title: Description
hierarchical_section_title: Swan / Description
caption_attribution_description: English: Höckerschwan (Cygnus olor) im Flug, Rheinkrippen bei Bingen am Rhein
context_page_description: Swans are birds of the family Anatidae within the genus Cygnus. The swans' closest relatives include the geese and ducks. Swans are grouped with the closely related geese in the subfamily Anserinae where they form the tribe Cygnini. Sometimes, they are considered a distinct subfamily, Cygninae. There are six living species of swan; in addition, there is a species known as the coscoroba swan which is no longer considered one of the true swans. Swans usually mate for life, although “divorce” sometimes occurs, particularly following nesting failure, and if a mate dies, the remaining swan will take up with another. The number of eggs in each clutch ranges from three to eight.
context_section_description: Swans are the largest extant members of the waterfowl family Anatidae, and are among the largest flying birds. The largest species, including the mute swan, trumpeter swan, and whooper swan, can reach a length of over 1.5 m (59 in) and weigh over 15 kg (33 lb). Their wingspans can be over 3.1 m (10 ft). Compared to the closely related geese, they are much larger and have proportionally larger feet and necks.  Quite unusual for birds, swans have "teeth" - jagged parts of their bill that are used for catching and eating fish. Adults also have a patch of unfeathered skin between the eyes and bill. The sexes are alike in plumage, but males are generally bigger and heavier than females.
  The Northern Hemisphere species of swan have pure white plumage, but the Southern Hemisphere species are mixed black and white. The Australian black swan (Cygnus atratus) is completely black except for the white flight feathers on its wings; the chicks of black swans are light grey. The South American black-necked swan has a white body with a black neck.
  Swans' legs are normally a dark blackish grey colour, except for the South American black-necked swan, which has pink legs. Bill colour varies: the four subarctic species have black bills with varying amounts of yellow, and all the others are patterned red and black. Although birds do not have teeth, swans have beaks with serrated edges that look like small jagged 'teeth' as part of their beaks used for catching and eating aquatic plants and algae, but also molluscs, small fish, frogs, and worms. The mute swan and black-necked swan have lumps at the base of their bills on the upper mandible.
caption: Mute swan landing on water. Due to the size and weight of most swans, large areas of open land or water are required to successfully take off and land.
exif: {"Image Make": "NIKON CORPORATION", "Image Model": "NIKON D80", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Ver.1.01", "Image DateTime": "2007:08:24 14:47:34", "Image ExifOffset": "196", "Image Tag 0x882A": "[2, 2]", "EXIF ExposureTime": "1/250", "EXIF FNumber": "8", "EXIF ExposureProgram": "Aperture Priority", "EXIF ISOSpeedRatings": "160", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2007:07:06 15:38:50", "EXIF DateTimeDigitized": "2007:07:06 15:38:50", "EXIF ShutterSpeedValue": "995723/125000", "EXIF ApertureValue": "6", "EXIF ExposureBiasValue": "-2/3", "EXIF MaxApertureValue": "49/10", "EXIF MeteringMode": "Pattern", "EXIF LightSource": "Cloudy weather", "EXIF Flash": "Flash did not fire", "EXIF FocalLength": "220", "EXIF SubSecTimeOriginal": "10", "EXIF SubSecTimeDigitized": "10", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CVAPattern": "[0, 2, 0, 2, 1, 2, 0, 1]", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Manual", "EXIF DigitalZoomRatio": "1", "EXIF FocalLengthIn35mmFilm": "330", "EXIF SceneCaptureType": "Standard", "EXIF GainControl": "None", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal", "EXIF SubjectDistanceRange": "0"}