| Case Summary for:
Submission No 360: Black-billed Cuckoo-Dove Macropygia nignirostris;
Darnley Island, Torres Strait, Queensland. 27th August 2002 (Unpublished). Verdict: Not Accepted This submission relates to the sighting of a bird considered to be a Black-billed Cuckoo-Dove by one member of a party of birdwatchers visiting Darnley Island in Torres Strait on the 27th August 2002. The bird was observed on a dry metal road close to the airport and was in view for an estimated 2 minutes, providing the observer with the opportunity to note salient features. Other birdwatchers were alerted to its presence but unfortunately it was not relocated. The observer quickly recognised the dove as a Macropygia by its "low to the ground stance and attenuated profile, mainly the long tail". It was estimated to be a little more robust than the familiar Bar-shouldered Dove Geopelia humeralis, which is common on the island, and had a longer tail. Key features noted include: "a rusty brown head, neck and body (with no barring or spotting), slightly darker brown upperwing coverts, and blackish primary tips. The longish tail was brown with barring on the upper surface. The bill was black, legs & toes reddish. Both Brown Cuckoo-Dove M. amboinensis and Mackinlay's Cuckoo-Dove M. mackinlayi have plain tails so were easily eliminated. Members agreed that identity in this instance relies heavily on the barred-tail. Of all the Macropygia only nignirostris displays a barred tail. Votes resulted in a mixed response; those voting in favour noting the experience of the observer and the clear presence of the barred tail and those voting against did so due to the brevity of the sighting, the lack of any opportunity to take field notes or photographs, the lack of any direct size comparison or other corroboration. Single observer sightings of species new to Australia are traditionally very difficult to accept when views are brief. Coates (1985) describes this species as "a medium sized pigeon with a long broad tail. Plumage generally rufous-brown, darker on wings, tail rich chestnut barred with black; iris variable (red, yellow, white or brown); orbital skin red; bill black or brown; legs and feet red or brown. Sexes similar but female faintly barred and mottled with black all over. And with tail more clearly barred than in male. In sub-adults the tail is irregularly barred". Coates also states that: "this species occasionally comes to the ground to drink from pools at the forest edge in dry weather". Thus the presence of an individual of the claimed species on the ground in open country would be very much out of character. Very little is known about the movements of Black-billed Cuckoo-Dove,
although (Coates 1985) does indicate that this species is more common
in the hills within mainland New Guinea and that this species has been
recorded as a vagrant to Watom Island, East New Britain Province (Coates
1985). The bird sighted here may well have been a Black-billed Cuckoo-Dove
but the committee was unable to reach the minimum requirement (7 out 8
votes in favour of acceptance) to reach a positive outcome.
· Beelher, B.M., et.al. 1986. Birds of New Guinea. Princeton
University Press, New Jersey.
Tony Palliser
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