Milan Radisics / Ducks silhouetted at night on Heroes Square, Budapest, July 2009

David Pattyn / Tufted duck (Aytha fuligula) portrait, sleeping male in breeding plumage. The Netherlands. March.

David Pattyn / Tufted duck (Aytha fuligula) portrait of a male in breeding plumage. The Netherlands. March.

David Pattyn / Tufted duck (Aytha fuligula) portrait of a male in breeding plumage. The Netherlands. March.

Gabriel Rojo / Brazilian duck (Amazonetta brasiliensis) male Ibera Marshes, Corrientes Province, Argentina

Gabriel Rojo / Black-bellied whistling ducks (Dendrocygna autumnalis) group in flight, Ibera Marshes, Corrientes Province, Argentina.

Michael Hutchinson / Brazilian teal {Amazonetta brasiliensis} on marshes, Esteros del Ibera, Argentina

Rod Williams / Brazilian teal {Amazonetta brasiliensis} male with female behind, captive, from Eastern South America

Pete Oxford / Brazilian Teal (Amazonetta brasiliensis) in wetlands, Pantanal, Mato Grosso do Sul, Brazil

Rod Williams / Brazilian Teal (Amazonette brasiliensis ipecutiri) male female pair, Male on right. Captive occurs in South America. .Captive

David Perpinan / Brazilian teal (Amazonetta brasiliensis) pair (male right and female left) resting on the shore of a marshland, Pantanal Mato Grosso do Sul, Brazil,