The Coscoroba Swan is a species of waterfowl endemic to southern South America. It is the smallest of the birds called "swans", but still a large species of waterfowl.
The Coscoroba Swan feeds mainly on grasses and small water plants, but also mussels and fish. The female incubates the eggs, while the male stands guard and aggressively helps to protect the fledglings against predators after hatching. Coscoroba Swans live to an age of approximately twenty years.
The Coscoroba Swan breeds in South America from southern Chile and central Argentina south to Tierra del Fuego and the Falkland Islands. In winter it flies north to central Chile, northern Argentina, Uruguay and the southeast tip of Brazil.
Its habitat is well-vegetated swamps and lagoons. Its population is estimated at 10,000–25,000 birds.