Little Corella
Cacatua sanguinea

Little Corellas are members of the cockatoo genus. They are native to most of central Australia, but in the Sydney area, they are thought to be introduced although they may have been present before westerners landed. They can form huge flocks and in Sydney are usually found in parks and grassland. Smaller numbers of Long-billed Corellas can also be found in Sydney and differ mainly in beak length and the amount of red around the face - the little having less.
 

1: Victoria Park, Sydney, 26/02/2010.