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COCKATOOS Cacatuidae |
- 21 species in Australasia and islands off southeast Asia
- DR personal total: 9 species (43%), 4 photo'd
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Cockatoos
are a family of (mostly) large psittaciformes in Australasia, although
they range from Australia to the Bismarck Archipelago and the
Philippines. They differ from other parrot-like birds in various
internal ways (e.g., they have a gall bladder), their downy hatchlings,
and the lack of green or blue in their plumage. Thirteen of the 21
cockatoos are white or mostly white, including such large birds as Sulphur-crested Cockatoo (left) of east and north Australia and New Guinea.
Cockatoos
are striking birds of forest, eucalypt woods, or more open country,
depending on species. Coming as I do from the northern hemisphere, I
was very impressed by my first view of such a big white bird in flight.
The size and manner of flight strongly recalled Snowy Owl to me, and
I've had that strange image ever since. |
Another
7 of the cockatoos are black, blackish, or gray; an example is
Yellow-tailed Black-Cockatoo of southeast Australia (right, in a
wonderful shot by Hans & Judy Beste). These big dark birds are also
very impressive in flight. The five species of black-cockatoo somewhat
replace each other geographically, except in southwest Australia where
two very similar species occur sympatrically, and survive because they
differ in bill length and thus eat different seeds.
While
the molecular (de Kloet & de Kloet 2005) and morphological evidence
(e.g., Homberger 1991) has shown that cockatoos are an ancient and
distinct lineage within the psittaciformes, whether to separate them as
a family is debated. Dickinson (2003) preferred to keep all the
psittaciformes in one family. The Handbook of the Birds of the World
series split the psittacines into two families: parrots and cockatoos
(Rowley 1997). Christidis & Boles (2008) add a further family to
that set — New Zealand parrots [Nestoridae] — and others have proposed even more splits. For the moment, I follow Christidis & Boles (2008) in a three-way split. |
| The most widespread cockatoo in Australia is Galah
(below), with its rosy face and underparts, white crown, and gray
upperparts. It was once a bird of the arid interior but, as it is well
adapted to open country, has expanded its range with human settlement
and agricultural development (Rowley 1997). Galah are sociable birds
and can be found in flocks up to 1000 birds. Like most parrots,
cockatoos are monogamous and pair for life. These two (below) appeared
to be mates. |
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The three corellas in Australia are smaller white cockatoos of open country. This is Long-billed Corella
of the southeast (left & below). The one (left) had a favored
century plant in the center of the little town of Deniliquin, New South
Wales, and you can see how it has ripped up that plant while sharpening
its bill.
On my first trip to Australia with two
friends, we took turns driving the rental car. My friend Steve was
driving when I spotted what looked like a bunch of birds out in a
field, so I suggested that we turn around and check them out. "Nah,"
said Steve, who had seen them from the corner of his eye, "it was just
a field full of sheep." But I insisted that they were birds, so we went
back — and found a flock of Little Corella Cacatua sanguinea.
A flock of Long-billed Corella on the ground (below) can still give one
that same image — and of course I now think "sheep" when I encounter
such a flock. |
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Cockatiel Nymphicus hollandicus
is the smallest member of this family; it wanders erratically
throughout the Australian interior. Many Cockatiel are now bred in
captivity, where it is among the most popular of all cage-birds.
Seven
cockatoos are found on islands between New Guinea and the Philippines;
four of them are globally threatened (Birdlife International 2000). One
of those is the beautiful Philippine (or Red-vented) Cockatoo Cacatua haematuropygia,
a Philippine endemic and now rare and local to a few of the southern
islands. When I first visited the Philippines in 1990, our group saw a
pair on the Palawan Island mainland, where a pair flew over us as we
walked along a stream. I wrote: "This is a lovely white small cockatoo;
a bit of yellow wash to the back of the head & bright salmon
undertail coverts." When I returned to the Philippines 15 years later,
this species was almost entirely gone from the main forest of Palawan,
and there were no longer any predictable spots of occurrence. To see
it, one took a boat to a tiny offshore islet, and watched a few fly in
at dusk. Views were limited to white birds in flight a long distance
away from a rocking dinghy. The experience is no longer the same. Let's
hope, though, that they will make a comeback in the future. |
Photos: The Sulphur-crested Cockatoo Cacatua galerita was in Royal Nat'l Park, New South Wales, Australia, in Dec 1997. Hans & Judy Beste photographed the Yellow-tailed Black-Cockatoo Calyptorhunchus funereus in eastern Australia. The pair of Galah Eolophus roseicapillus and the Long-billed Corella Cacatua tenuirostris were at Deniliquin, New South Wales; the Galah on 1 Jan 1998, and the corellas on 31 Dec 1997. Photos © Don Roberson, except for the black-cockatoo © Hans & Judy Beste, used with permission; all rights reserved.
Bibliographic note: Cockatoos have been traditionally covered by books covering psittaciformes; see reviews of family books on my Parrots page.
Literature cited:
Birdlife International. 2000. Threatened Birds of the World. Barcelona, Lynx Edicions.
Christidis, L, and W.E. Boles. 2008. Systematics and taxonomy of Australian Birds. CSIRO Publ, Sydney.
de
Kloet, R.S., and S.R. de Kloet. 2005. The evolution of the spindlin
gene in birds: Sequence analysis of an intron of the spindlin W and Z
gene reveals four major divisions of the Psittaciformes. Molec. Phylog.
Evol. 36: 706-721.
Dickinson, E., ed. 2003. The
Howard & Moore Complete Checklist of the Birds of the World. 3d ed.
Princeton Univ. Press, Princeton, N.J.
Homberger, D.G. 1991. The evolutionary history of parrots and cockatoos: a model for evolution in the Australasian avifauna, in
Acta XX Congress Internationalis Ornitholigici (Bell, B.D., et al.,
eds.). Vols. 1–4. New Zealand Ornithol. Congress Trust Board,
Wellington.
Rowley, I. 1997. Family Cacatuidae (Cockatoos), pp. 246 –279 in Handbook of the Birds of the World (del Hoyo, J., A. Elliott & J. Sargatal, eds). Vol. 4. Lynx Edicions, Barcelona, Spain.
Sibley,
C.G., and J.E. Ahlquist. 1990. Phylogeny and Classification of Birds: a
Study of Molecular Evolution. Yale Univ. Press, New Haven, CT.
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