Lynn M. Stone / Umbrella cockatoo (Cacatua alba), portrait. Captive.

Lynn M. Stone / Sulphur-crested cockatoo (Cacatua galerita) perched on branch with palm leaves in background. Captive.

Ernie Janes / Sulphur-crested cockatoo (Cacatua galerita) Hobart Botanical Garden, Tasmania, Australia.

Ernie Janes / Sulphur-crested cockatoo (Cacatua galerita) flock in flight over Hobart Botanical Garden Tasmania, Australia.

Konrad Wothe / Galahs (Cacatua roseicapillus albiceps) drinking, Sturt National Park, New South Wales, Australia.

Staffan Widstrand / Dead Sulphur-crested cockatoo (Cacatua galerita) with ants crawling all over it. Lowland rainforest, Karawawi River, Kumawa Peninsula, mainland New Guinea, Western Papua

Frederique Olivier / Little corellas (Cacatua sanguinea) pair grooming each other, Pilgonaman Gorge, Cape Range National Park, Western Australia.

Konrad Wothe / Palm cockatoo (Probosciger aterrimus) displaying, Cape York Peninsula, North Queensland, Australia.

Konrad Wothe / Palm cockatoo (Probosciger aterrimus) perched in the wind, Cape York Peninsula, North Queensland, Australia.

Konrad Wothe / Palm cockatoo (Probosciger aterrimus) displaying, Cape York Peninsula, North Queensland, Australia.

Konrad Wothe / Palm cockatoo (Probosciger aterrimus) displaying and vocalising, Cape York Peninsula, North Queensland, Australia.

Konrad Wothe / Palm cockatoo (Probosciger aterrimus) displaying and vocalising, Cape York Peninsula, North Queensland, Australia.