The black-necked swan (Cygnus melancoryphus) is the largest South American waterfowl – it is found in only Brazil, Argentina, Chile and Uruguay. melancoryphus means black pigment. A red knob or carbuncle at the base of the upper mandible is enlarged in males at breeding season. The black-necked swan has short wings, but still is a fast flyer – of the eight swan species they are the fastest, achieving flight speeds of 50 mph! The black-necked swan has legs that are so well adapted to swimming that it is almost incapable of walking on land. Black-necked swans are unique in that both parents carry their young on their back for the first three weeks of life.