BrokenWing Chronicles
Short Billed/Long Billed Cockatoos
Long-billed Black Cockatoo
Two almost-identical species of white-tailed black cockatoo, with partly overlapping range. Differences in habitat preference and use, and calls that, while similar, are sufficiently distinctive to be useful in separating the species in the field, when in localities where either may be found, and where the often hidden, long fine bill tip cannot be seen. The Long-billed (Calyptorhynchus baudinii) is also known as Baudin's Cockatoo, the Short-billed (Calyptorhynchus latirostris) is often, locally, Carnaby's Cockatoo.
Long-billed Black-Cockatoo ( Baudin's)
with Eucalyptus calophylla seed capsule.The long fine tip of the bill is often hidden in feathers, difficult to see in side view, except when bill is opened. From the front, the bill appears narrower than that of the short-billed species.
The Short-billed Black Cockatoo (Carnaby's)
lacks the very finely pointed bill tips, and may also be obscured by feathers in side view. From the front, it looks wider than that of the long-billed species.
A pair of Short-billed Black Cockatoos feeding on a grevillea shrub. Unlike the long-billed, this species usually must feed upon more accessible seeds, such as those of banksias, grevilleas, hakeas and dryandras. Here the flowers of Grevillea eriostachya are chopped apart for nectar or other food content; the flock soon leaves the ground littered with the fallen flowers.
But the fine-pointed bill of the Long-billed Black Cockatoo enables it to pry the seeds from very hard wooden fruits of the Marri, which is the common food tree for the species. This species occupies wetter and more heavily forested coastal regions; the short billed species is usually further north and inland, in drier woodlands, but with substantial range and habitat overlap.
Short-billed Black Cockatoo
The flock moves on from tree to tree or shrub of open forest, woodland or sandplain, their noisy wailing calls making them impossible to overlook. As they dive away, then swoop up to the next perch, the white panels in the tail show conspicuously with the spreading of these feathers.
This extensive cluster of flowering grevilleas, covering an area of perhaps 10 acres, attracted a large number and diversity of birds, for the surrounding bushland was in drought, and poor both in wildflowers and birds. Calls also include other birds feeding on nearby flowers.
These birds, together with the Red-tailed Black Cockatoo, are are now subject of long-term research by the Western Australian Museum. A public awareness programme, Cockatoo Care, is aimed at focussing attention upon their survival requirements. This is being supported by the W.A.Water Corporation, whose forest catchment areas are a vital part of the habitat for these birds. Further information:
www.cockatoocare.com and
www.museum.wa.gov.au
NAMING and RELATIONSHIPS of the WHITE-TAILED BLACK-COCKATOOS of South-Western Australia: LONG-BILLED (BAUDIN'S) and SHORT-BILLED (CARNABY'S)
The similar Long-billed (Baudin's) and Short-billed (Latham's) Black-Cockatoos have 'progressed' from being combined as one together as a race of the eastern Yellow-tailed Black Cockatoo, to being now two full species, both are white-tailed.
It is only in comparatively recent times that the Short-billed and the Long-billed Black-Cockatoos have been recognized as being each a full species. Not so very far back ornithologists were unaware that there was any variation at all within the White-tailed Black-Cockatoo,.
Early recognition was from Serventy and Whittell, In Birds of Western Australia ( Paterson Brokensha , Perth, 1948, 1962 revised edition) They list only the one white-tailed species, C baudinii, but uniquely they recognize three races (page 245: "Two well-marked sub-species occur. In the forested South-West corner is a form with a narrow bill (tenuirostris) and to the east of Albany, ...is found the heavy-billed race with the mandible shortened (latirostris, I.C. Carnaby). They keep baudinii as the nominate, presumably covering White-tailed Black-Cockatoos elsewhere in WA.
Forshaw in his major work in 1969 on this family (Forshaw J. M., Australian Parrots, Lansdowne Press, Melbourne, 1969), lists just three species of black-cockatoo, these being the Black Cockatoo, Calyptorhynchus funereus , the Red-tailed Black-Cockatoo (C. magnificus), and the Glossy Cockatoo (C. lathami).
In that work Forshaw describes (page 53) , apart from the yellow-tailed nominate race lathami of eastern Australia, just one Western Australian race, C. funereus baudinii, with a range extending from approximately the Murchison River south to near Esperance. He states that it is known as the White-tailed Black-Cockatoo or Baudin's Cockatoo.
Forshaw seems to put little faith in above publications, saying "there may be two distinct populations in south-western Australia. The bills of the birds from the extreme south-western corner are said to be longer and narrower than those of inland birds." The differences of bill shape had previously led Carnaby (1948) to describe the shorter-billed form as race latirostris from a specimen collected at Hopetoun.
Continued