Not always pretty. This cockatoo is suffering from 'beak and feather' disease.
Semi urban fringe, open dry sclerophyll forest.
This area was mid-way through one of the worst droughts on record when this disease took hold. I estimated that 70% were showing signs of disease and eventually about 30% died from it. Things may have been exacerbated by people feeding them as feeding stations become centres for infection. This viral disease is amazing in that it cleverly affects all except flight feathers and spreads via the 'dust' of the failing feathers. The beak is also badly affected meaning many birds die from starvation. Glad it's all over.