It has a unique territorial display where the bird (typically the male) drums with a large (i.e. up to 2.5 cm diameter, 15 cm long) stick or seed pod against a dead bough or tree, creating a loud noise that can be heard up to 100 m away. After drumming, the male occasionally strips the drum tool into small pieces to line the nest. Although this drumming behaviour was discovered over three decades ago (in 1984 by G.A. Wood), the reason why palm cockatoos drum is still a mystery. One reason could be that females can assess the durability of the nesting hollow by the resonance of the drumming. Another possibility could be that males drum to mark their territory against other males. The palm cockatoo is an unusual bird, being an ancient species and one of the few bird species known to use tools.
Breeding Palm cockatoos only lay one egg every second year and have one of the lowest breeding success rates reported for any species of parrot. Offsetting this is their very long lifespan. A male commenced breeding at 29 in
Taronga Zoo in Sydney, and a female at the London Zoo was 40 when she laid her first egg in 1966. Breeding takes place inside tree hollows that look like standing pipes. Fires play an important role in the destruction and creation of nest hollows. Fires allow the colonisation of microorganisms and termites, which enter the tree and start hollowing out the inside. Cyclones are important in the final stage of nest hollow development. Anecdotal evidence indicates a palm cockatoo reaching 80 or 90 years of age in an Australian zoo, Although longevity of captive birds is known, the lifespan of palm cockatoos that live in the wild is still unknown.
Food and feeding The palm cockatoo often feeds during the early hours of the day, on a diet consisting mostly of wild
pandanus palm fruits and
kanari tree nuts. They have also been seen eating fruits of
Darwin stringy bark and the
nonda tree, as well as seeds from the
cocky apple tree,
beach almond and
black bean tree. ==Conservation and status==