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The ability to identify individuals within a population is often essential for a detailed understanding of the ecology and conservation of a species. However, some species, including large parrots, are notoriously difficult to catch and mark for individual identification. Palm cockatoos (Probosciger aterrimus) are a large, poorly understood species of parrot which are likely in severe decline within the eastern part – and possibly the western part – of their range on Cape York Peninsula, Australia. Here, we investigated whether three different palm cockatoo call types are sufficiently individually distinctive to function as a non-invasive “marker” for identifying individuals over time. Using Discriminant Function Analysis, overall identification accuracy among 12 putative individuals for all call types was 81% (i.e. 148 out of 183 calls were assigned to the correct individual) on the basis of multiple temporal, energy (amplitude) and frequency measurements on the spectrogram. For three different c...

Vocal dialects have been well studied in songbirds, but there have been fewer examples from parrots. The Australian population of palm cockatoos (Probosciger aterrimus aterrimus) from Cape York Peninsula in far north Queensland has an unusually large vocal repertoire for a parrot. Most calls are made during their unique display ritual, which also includes a variety of postures, gestures and the use of a manufactured sound tool. Here, we quantify the geographic structural variation of contact calls within and between six major populations of palm cockatoos in Australia, as well as the extent to which frequently given call types are shared. We found that palm cockatoos from the east coast (Iron Range National Park) possess unique contact calls and have fewer call types in common with other locations. This may have resulted from their long-term isolation in rainforest habitat refugia. Such variety in vocal traits presents a rare opportunity to investigate the evolutionary forces creating behavioural ...

Parrots are renowned for their capacity for vocal learning and production of diverse sounds in captivity, yet little is known about why such advanced vocal capabilities have evolved. Here, we provide a detailed description and statistical classification of the vocal repertoire of wild palm cockatoos Probosciger aterrimus and investigate the behavioural contexts of vocalizations. We show that palm cockatoos produce vocalizations that conform to most of the common vocalizations described for wild parrots, but also produce a variety of additional syllables in a phonological syntactic manner in the contexts of display and vocal-exchange with neighbouring individuals. These additional syllables are mainly produced by males and are often combined to form long, complex sequences. Unlike most parrots, palm cockatoos defend large multipurpose territories and we speculate that the large vocal repertoire and vocal assemblages of palm cockatoos may function in territorial defense.

In a rare parallel with human instrumental music, wild palm cockatoos manufacture sound tools and produce a rhythmic beat., All human societies have music with a rhythmic “beat,” typically produced with percussive instruments such as drums. The set of capacities that allows humans to produce and perceive music appears to be deeply rooted in human biology, but an understanding of its evolutionary origins requires cross-taxa comparisons. We show that drumming by palm cockatoos (Probosciger aterrimus) shares the key rudiments of human instrumental music, including manufacture of a sound tool, performance in a consistent context, regular beat production, repeated components, and individual styles. Over 131 drumming sequences produced by 18 males, the beats occurred at nonrandom, regular intervals, yet individual males differed significantly in the shape parameters describing the distribution of their beat patterns, indicating individual drumming styles. Autocorrelation analyses of the longest drumming sequences further showed that they were highly regular and predictable like human music. These discoveries provide a rare comparative perspective on the evolution of rhythmicity and instrumental music in our own species, and show that a preference for a regular beat can have other origins before being co-opted into group-based music and dance.

Habitat destruction, hunting and poaching for illegal trade are threatening the long-term survival of the Palm cockatoo Probosciger aterrimus. In 1983 the confiscation of 103 Palm cockatoos by the US Fish and Wildlife Service led to the formation of a breeding consortium, which in 1988 was formalized as an American Zoo and Aquarium Association SSP (Species Survival Plan). Details of the natural history, physical traits and behaviour of Palm cockatoos are given. Enclosure design, captive management and the development and goals of the Palm cockatoo SSP are also described.

Since the mid-1980s 22 Palm cockatoos Probosciger aterrimus (10.7 adults and 2.1.2 young birds) have been maintained at Rotterdam Zoo. Health problems and husbandry experiences with this species are recounted here. Nine (5.4) adults died, five within 2 years of acquisition through governmental confiscation. Three ♂♂were relocated to other zoos which had single ♀♀ Since 199! ten eggs (nine fertile) have been produced collectively by two ♀♀ with three ♂♂ Five eggs hatched, from which two chicks which were being hand-reared died, one at 6 weeks and one at 6 months of age. One chick was unsuccessfully fostered by a pair of Red-sided eclectus parrots Eclectus roratus polychloros and two chicks were successfully parent-reared: a ♀ in 1995 and a ♂ in 1997.

The karyotypes of three species of cockatoos, Cacatua moluccensis, Cacatua goffini, and Cacatua sanguinea, and one Amazon parrot, Amazona aestiva, are described for the first time. These karyotypes are compared to the twenty-three species of psittacines published previously. Cacatua moluccensis appears to be a link in the evolutionary tree between Probosciger aterrimus and the other cockatoo species studied. This study reaffirms that the cockatoos are probably most closely related to the loris (Loriculus sp.) and Amazon parrots based on karyotype (M. W. M. Van Dongen & L. E. M. De Boer, (Genetica 65: 109–117) 1984).