Several male cockatoos do this. It is done to show strength or dominance. The bird is stating, “This perch belongs to me” It is likely that the bird prefers the owner to back off; however, sometimes this is just a bluff. Some cockatoos behave that way to gain the owner’s attention. Male black palm cockatoos, (a large black bird available in Northern Australia, New Guinea, and Indonesia) usually holds a large stick and bang it on a tree to inform other birds that a certain nesting spot is booked.
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