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

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

Jiri Lochman / Major Mitchell's cockatoo (Cacatua leadbeateri) flock, Willandra Lakes UNESCO Natural World Heritage Site, New South Wales, Australia.

Jiri Lochman / Galah cockatoo (Cacatua roseicapilla) flock at water, Willandra Lakes UNESCO Natural World Heritage Site, New South Wales, Australia.

Jiri Lochman / Sulphur-creasted cockatoo (Cacatua galerita) pair, one displaying to another, Wollemi National Park, Greater Blue Mountains UNESCO Natural World Heritage Site, New South Wales.

Roger Powell / Sulphur-crested cockatoo (Cacatua galerita) looking down from a fir tree, Halls Gap, Victoria, Australia.

Roger Powell / Sulphur-crested cockatoo (Cacatua galerita) resting in a eucalyptus tree, Halls Gap, Victoria, Australia.

Roger Powell / Young woman feeding Sulphur-crested cockatoos (Cacatua galerita) in a park, Sherbourne, Victoria, Australia.

Roger Powell / Little corella (Cacatua sanguinea) male displaying to female from the top of a tree. Mary River Park, Northern Territory, Australia,

Roger Powell / Little corella (Cacatua sanguinea) feeding on a eucalyptus nut in the tree canopy. Mary River Park, Northern Territory, Australia,

Roger Powell / Four little corellas (Cacatua sanguinea) gathering on a branch before flying to their roost. Mary River, Northern Territory, australia,

Tim Laman / Sulphur-crested cockatoo (Cacatua galerita) in swampy area of rainforest, New Guinea, June.