Inhabits Paraguay, Uruguay, Chile, Argentina and Brazil. Lives in shallow water tanks – lakes, ponds, sea bays and swamps. Those shallow waters provide a wide variety of water plants, seeds and small invertebrates, all of which form the basis of Coscorobas diet.
Birds live in pairs, rarely in small groups. A pair occupies a selected territory, which they can effectively defend for many seasons. Coscorobas migrate, but part of population remains on breeding grounds throughout the year. It builds a nest in a place with easy access to water. The female lays up to 9 eggs and incubates them herself, while the male defends the chicks and the territory. As Coscorobas are precocials, young birds follow their mother after hatching and search for food on the bottom of the water reservoir.
- Latin name: Coscoroba coscoroba
- IUCN – Red List – LC – Least concern