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Case Summary for:
Submission No 239: Green Sandpiper Tringa ochropus; Darwin Rubbish Tip, NT, 4th March 1998. Submitted by Niven McCrie. Verdict: Accepted This case relates to a sighting of a sandpiper on a roadside puddle close to the Darwin rubbish tip on the 4th March 1998. The bird was viewed using binoculars at a distance estimated to be less than 20 metres and although brief were considered by the observer to be excellent. Despite exhaustive searches the bird was not relocated. As described the bird was superficially similar to a Wood Sandpiper Tringa glareola. Quoting directly from the submission: "The crown was dark, heavily streaked and lacking any sense of a 'cap' (as frequently seen on Wood Sandpipers)". "Ear coverts were dark and streaked laterally". "Bold pure white eye-ring, with broad pure white supercilium extending from the eye forward to the bill, but not extending behind the eye". Upperparts were "dark grey-brown, with no conspicuous spotting or pale feather edges". Although some fairly dull spotting was present on the wing coverts. "Rump and tail extensively white". The breast was dark, streaked and clearly demarcated from the white underparts. Legs were dull dark-grey-green. Importantly, the underwing was seen clearly and this was described and sketched to show a very dark wing lining, darker than the primaries, which were dark grey, perhaps brownish. Some whitish spotting on the underwing lining was clearly seen, although a distinct pattern was not apparent; rather just scattering of spots on a dark wing lining. There was no area of white or even pale areas to the underwing lining. The upperwing was "dark without any white markings and the intensity of the white rump & tail was no doubt enhanced by the darkness of the back and wings and the black barring at the end of the tail". Also of importance was the call which was described as a loud rather shrill "tee-tee-tee". Direct comparison with Wood Sandpiper was not possible at the time of the sighting. However, the observer did make an effort to view Wood Sandpipers successfully the following day and some comparative notes were made and presented to the committee as part of the submission. After the first round of voting several members felt that the evidence (as is so often the case with single observer sightings) was insufficient to warrant acceptance as a first for Australia. Some of the material was open to uncertainty and considered not entirely convincing. The extent of the black & white appearance was insufficiently emphasized, the description of the call was open to interpretation, the tail should perhaps (in the view of one member) be mostly black not mostly white and the contrasting underwing contradicts (in part) available literature and significantly, information relating to the diagnostically shorter legs of a Green Sandpiper, which do not trail beyond the tail in flight was not available. After two more rounds of voting it was determined that the observers extensive experience with Wood Sandpiper and the many positive aspects to this record were hard to ignore: · The extensively white rump and tail contrasting the dark back and wings and with bold black subterminal bands to tail fits the general (i.e. rather black & white) impression one gets of a Green Sandpiper on flushing and although the number of bands was not accurately discerned, the sketches clearly show them as relatively broad and black bands clustered near the end of the tail (cf. narrower and much duller greyish bands that occupy a greater area of the tail in Wood Sandpiper; see illustrations in Shorebirds). · The very dark underwing, with coverts described as darker than the remiges (and apparently spotted whitish) is diagnostic and rules out any thought of Wood Sandpiper, which has a much paler greyish underwing with coverts whitish and finely barred and spotted grey and appearing noticeably paler than the remiges. The fact that the observer checked his field impression of the Green against Wood Sandpipers the following day and confirmed these fundamental differences is further evidence in support of the identification as Green Sandpiper. The fact that the coverts were described as spotted rather than barred or spotted and barred white is of little importance as the precise nature of the markings is (and was) difficult to discern without exceptionally clear views. · The general shape and proportions and the overall rather contrasting dark & white plumage pattern as shown in the sketches agree well with the species, as does the description of dark grey-green legs. · The flight call agrees well with the descriptions in Chandler (1989) and Shorebirds; that the call transcription doesn't agree precisely is of little importance as these vary widely because perceptions differ; what is important is that the pattern of the call fits, which it does. That the observer noted a clear difference between this call and that of Wood Sandpipers when listening to the latter the following day also supports this aspect of the identification. Considering the date of observation and the description of the upperparts (clearly pale-spotted only on the wing-coverts and tertials cf. the mantle, back and scapulars), it seems reasonable to surmise that the bird was in non-breeding plumage. But whether in adult or first immature plumage one cannot say for certain. The committee resolving after a third and final round to accept this record as Australia's first as a Green Sandpiper Tringa ochropus. A non-breeding bird of unknown age.
References and Bibliography
Tony Palliser |