Konrad Wothe,Konrad Wothe / Greater Rhea (Rhea americana) male, Pantanal, Brazil, South America

Gabriel Rojo / Greater rhea (Rhea americana) eggs in nest, at edge of arable field. Patagonia, Argentina. October.

Gabriel Rojo / Greater rhea (Rhea americana) nest with many eggs, at edge of arable field. Patagonia, Argentina. October.

Angelo Gandolfi / Greater rhea (Rhea americana), three feeding on agricultural land. Brazil.

Angelo Gandolfi / Greater rhea (Rhea americana), six walking across grassland. Cerrado, Brazil.

Franco Banfi / Greater rhea (Rhea americana) Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / Greater rhea (Rhea americana) Pantanal wetlands, Mato Grosso, Brazil

Luke Massey / Rhea (Rhea americana) chicks, Pantanal, Brazil.

Luke Massey / Rhea (Rhea americana) chicks, Pantanal, Brazil.

Luke Massey / Rhea (Rhea americana) male with his chicks, Pantanal, Brazil.

Luke Massey / Rhea (Rhea americana) male with his chicks, Pantanal, Brazil.

Sylvain Cordier / Greater Rhea (Rhea americana) chicks, Torres del Paine National Park, Patagonia, Chile.

Hermann Brehm / Greater Rhea (Rhea americana) profile, Pantanal, Brazil

Gabriel Rojo / Common rhea, (Rhea americana) head portrait, La Pampa, Argentina

Bernard Castelein / Greater Rhea (Rhea Americana) walking, St Cruz le la Sierra, Bolivia

Sylvain Cordier / Greater rhea (Rhea americana) two birds fighting, Punta Norte, Peninsula Valdes, Argentina

Sylvain Cordier / Greater rhea (Rhea americana) fight between two birds, Punta Norte, Peninsula Valdes, Argentina.

Barrie Britton / Greater rhea (Rhea americana), Fazenda Baia das Pedras, Pantanal, Brazil. Taken on location for BBC Wild Brazil series.

Gabriel Rojo / Greater rhea eggs (Rhea americana) La Pampa , Argentina

Suzi Eszterhas / Greater rhea (Rhea americana) walking through Pantanal, Brazil.

Gabriel Rojo / Greater rhea (Rhea americana) resting on grass, La Pampa , Argentina

Gabriel Rojo / Greater rhea (Rhea americana) portrait, La Pampa, Argentina

Roland Seitre / Greater Rhea (Rhea americana) chicks, Argentina, captive.

Roland Seitre / Greater rhea (Rhea americana araneipes) Beni, Bolivia.

Roland Seitre / Greater rhea (Rhea americana araneipes) Beni, Bolivia.

Roland Seitre / Greater rhea (Rhea americana araneipes) Beni, Bolivia.

Angelo Gandolfi / Greater rhea (Rhea americana) feeding, Brazil.

Angelo Gandolfi / Greater rhea (Rhea americana) portrait, Brazil.

Angelo Gandolfi / Greater Rheas (Rhea americana) in mating display, Brazil.

Nick Upton / Greater rhea (Rhea americana) pair looking around. Captive.

Nick Upton / Greater rhea (Rhea americana) portrait. Captive.

Nick Upton / Greater rhea (Rhea americana) portrait. Captive.

Fernando Faciole / Greater rhea (Rhea americana) alert in Pantanal wetlands. Transpantaneira Highway, Pocone, Mato Grosso, Brazil.

Fernando Faciole / Greater rhea (Rhea americana), with five chicks, trying to drink at mud pool overcrowded with caimans due to ongoing drought. Transpantaneira Highway, Mato Grosso, Brazil.

Roland Seitre / Greater rhea (Rhea americana) standing over its clutch of eggs in nest, South America. Captive.

Roland Seitre / Greater Rhea (Rhea americana) protecting its clutch of eggs in nest. Argentina. Captive.