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Home , Stilt sandpiper

VOL. 14 (8) DECEMBER 1992 313

AUSTRALIAN WATCHER 1992, 14, 313-317

Stilt in non-breeding plumage, Avalon Saltworks, Victoria, 17 December 1990. Note tibia length. Plate 47 Photos: R. Bugg A Second Australian Sighting of the Micropalama himantopus

by FRED T.H. SMITH, 71 Cobden Street, Kew, Victoria 3101

Introduction The Stilt Sandpiper Micropalama himantopus is a long-distance migrant that breeds on wet and dry, arctic and subarctic tundras across North America (Johnsgard 1981). After breeding, it migrates south to north-eastern Argentina and rarely strays to other parts of the world (Hayman eta!. 1986). It has been recorded once before in Australasia, a bird in partial breeding plumage at Darwin, Northern Territory, in August 1980 (McKean 1981). This paper documents a second record from Australia, a bird in non-breeding plumage at the Avalon Saltworks near Geelong, Victoria, from 8 December 1990 to 3 March 1991, nearly 4000 km south-east of Darwin. Subsequently a third record was reported for Australia, at Alice Springs (N.T.), between the two previous localities, on 7 October 1991 (Benson 1991).

The sighting, with initial field notes Fred Anderson and I were observing at the eastern section of the A val on Saltworks (properly known as the Lara Operation of Cheetham Salt Ltd) on the morning of 8 December 1990, where large numbers of migratory waders and small numbers of Red-capped Plovers Charadrius ruficapillus were present. They were mostly at rest on flat muddy areas in a shallow salt evaporation pond, an intertidal roost and feeding area, a few metres from the shore of Corio Bay. Most numerous of the migratory waders were ferruginea, in their pale non-breeding plumage, except for one which, unusual for the time of year, was in complete breeding plumage. There were lesser numbers of Sharp-tailed Sandpipers C. acuminata and Red-necked C. ruficollis. Weather conditions were good at the time, with practically no wind and an overcast sky which gave a soft, even light that negated glare. Some waders were feeding in shallow water, (4 em deep, near the muddy flats. While closely observing the above species at about 1105 h, from a range of c. 45 m, with Bushnell Spacemaster II spotting scopes at 20 x magnification, we saw AUSTRALIAN 314 SMITH BIRD WATCHER a slightly deeper grey wader feeding near some winter-plumaged Curlew Sandpipers. At first it seemed to be a slightly darker , but there was something different in its posture and bill shape. I suspected it to be a Stilt Sandpiper, from its shape and my prior experience of Stilt Sandpipers in northern Canada (Front Cover, Plate 44), although those were in breeding and juvenile plumages and therefore different in appearance from the Avalon bird which was in non-breeding plumage (Plate 47). The bird was standing up to its abdomen in the shallow water, mostly with Curlew Sandpipers which were also abdomen-deep in the pond. For the first 20 minutes of observation the bird sometimes rested for several minutes in the water, often crouching behind a short, upright, broken stem or behind another wader, usually a Curlew Sandpiper, and occasionally behind a small group of waders. It was not feeding, just standing hunched at rest, in the water, and rarely changing position. After a while it began to wade and feed, mostly belly-deep but occasionally it showed part of the expected yellow-green of the tibia, which was clearly seen. Eventually it carne ashore and we were able to see the long, fine, spindly yellow­ green legs which confirmed its identity. We then wrote a field description.

Further observations The writer observed the bird on 11 separate days from the date of the original sighting, sometimes in company with Anderson, until it was last seen on 3 March 1991. The other dates were 15, 17 & 23 December 1990; 8, 17, 21 & 23 January 1991; and 9 & 23 February 1991. Most follow-up observations varied from at least one hour to several hours in duration. The bird was never seen on the mudflats, or wading in the shallows, of nearby Corio Bay. It preferred each of three adjoining, shallow salt-ponds with slightly elevated mudflats in them and upright, protruding, short, snag-like remnants of Shrubby Glasswort Sclerostegia arbuscula. There the Stilt Sandpiper was usually found wading belly-deep and feeding among the short snags. It was often the wader farthest out in the water but, later during its stay, slightly larger and longer-legged Marsh Sandpipers stagnatilis fed near it or in even deeper water. Having selected one of its preferred feeding places, the bird waded around steadily and unhurriedly, over a small area, probing its bill sporadically straight up and down into the water and soft mud below, often with its head and neck completely immersed. The feeding sessions, in one place, lasted from several minutes to over an hour. Although the bird seemed not to object to feeding in company and near other small waders such as Curlew and Sharp-tailed Sandpipers and Red-necked Stints, it often fed up to a metre from them, particularly in slightly deeper water where its longer legs gave it an advantage. A number of times the bird was discovered feeding alone, well away from other waders. Although the main feeding action was as described above, sometimes it fed close to a muddy edge where its legs were partly exposed and, rarely, out on the mudflat where they were completely exposed. In the latter positions, with legs partly or fully in view, it was observed engaging in another style of unexpected feeding activity, which was noted particularly on the first day of observation and seldom thereafter. It abandoned the deep probing and moved around, picking , mainly kelp flies, from the surface of the water, using a stalking and snatching action similar to that of Wilson's Phalaropus tricolor. The Stilt Sandpiper half crouched, with legs flexed, main!} in water, then leant forward and darted its bill straight ahead to take an from the surface. Sometimes it was seen stalking insects from the protruding short snags in a pond, occasionally completely inverting its bill to take a food item from a difficult crevice in a snag or similar situation. When feeding by VOL. 14 (8) DECEMBER 1992 Stilt Sandpiper, Second Australian Sighting 315

snatching, or with the head more erect, its neck appeared rather long. I found only one reference to a similar feeding practice: Bent (1927) mentioned the observation of J. T. Nichols who wrote, 'I have seen it alight on flooded dead marsh, wading in the puddles and picking at the projecting dead stubble about on its own level. ' Frequently, the Stilt Sandpiper suddenly flew up alone and went a long distance to another feeding place, usually in one of the other three shallow salt-ponds. It was then, while in flight, that the white rump, lack of wing-bar on the grey upperwings and the toes projecting well past the tail tip could be seen to advantage. On a few occasions it was noted at rest and sometimes preening, on the mudflat, usually with Curlew Sandpipers, where the full length of its legs could be seen. Although the body size of the Stilt Sandpiper seemed only fractionally greater than that of the Curlew Sandpipers, its long legs gave it a height advantage of several millimetres over them. On 17 January 1991, David Plant and Norman and Noreen McKendrick had the Stilt Sandpiper under observation for about an hour when, at approximately 1000 h, it suddenly flew high up and headed westward, out over nearby Corio Bay where it was lost from view. We left the saltworks and visited the Werribee sewage farm, about 10 km in a direct line north-east of the Avalon Saltworks, where after directions from Wally Coles we found the Stilt Sandpiper in marshland at about 1400 h. By appearance it seemed to be the A val on bird which, after flying westward earlier in the day from the saltworks, must have completely changed direction and flown north­ easterly to the sewage farm. This was the only time that it was noted away from the Avalon Saltworks. I noted it back at the saltworks on 21 January 1991. During February 1991 the breast, side and undertail covert streaking of the Stilt Sandpiper had become slightly more elongated, darker and more prominent, and a few scattered darker feathers were on the upperparts. These were the first signs of change to breeding plumage, and its state of plumage when last seen by the writer. . The Stilt Sandpiper was nearly always in company with Curlew Sandpipers and, because of their similarity in non-breeding plumage, it is considered worthwhile to list a few of the salient points of difference. The females of both species average slightly larger than males, mainly in bill, tarsus and wing length (Prater et al. 1977, Cramp & Simmons 1982, Hayman et al. 1986). Some of both species appear to be close in body size and bill length, but there is an obvious difference between them in length of tarsus and in leg colour. The feeding habits and postures of both species at A val on were similar, although the Stilt Sandpiper had a straighter up-and­ down motion of the bill when probing for food items.

Description The following description of the Stilt Sandpiper at Avalon Saltworks is from field notes by the writer. Upperparts: at rest, grey overall, a little deeper grey on crown. Primaries and tail blackish brown. Narrow supercilia off white, extending from near the forehead to rear of lower crown and nearly converging at that point. Dark mark on !ores from bill to eye. Small feathers of the upperparts and tertials narrowly fringed off white. The wing tips projected a few millimetres past the tail tip. (Originally the wing tip, or primary, projection was not as apparent and Robert Swindley suggested that this was because the primaries had not reached their full length following moult). Underparts: off white from chin to undertail coverts, with breast and sides of neck densely overlaid with short, grey streaks which continued more sparsely along the sides to the undertail coverts. Chin unstreaked. AUSTRALIAN 316 SMITH BIRD WATCHER

Bill: all dark. Long, nearly 1 1/z times the head length. Mostly straight, with a slight decurve distally. Straighter and thicker than in Curlew Sandpiper. Tip with less decurve and slightly thicker than in Curlew Sandpiper. Eyes: dark, with thin, pale orbital ring. Legs: greenish yellow (yellower in good light when wet) . Long, appearing thin and spindly probably because oftheir length. Noticeably longer than in Curlew Sandpiper when both species seen together on shore. Call: not heard during period of observation. Upperparts in flight: long-winged, grey generally, primaries and tail darker, no wing­ bar; prominent white rump; all of toes projecting well past tail tip. (Underwing coverts mostly white) . Towards the end of its stay, the Stilt Sandpiper developed a few scattered dark feathers on the upperparts and there was a small amount of dark flecking on the undertail coverts. The grey streaks on the breast, sides and undertail coverts became darker and more prominent.

Discussion The illustration 208b, Plate 85 in Hayman et al. (1986) of an adult non-breeding Stilt Sandpiper is closely similar to the A val on bird which, however, was slightly deeper grey overall on the upperparts, and the supercilium was less distinct towards the forehead than the one they depict. A photograph on p. 125 of Chandler (1989) is of a first-winter bird, with mantle ruffled, and is reminiscent of the Avalon bird. Apart from its upperparts being noticeably deeper grey than those of the Curlew Sandpiper (the shade of grey being more like that of a Grey-tailed Tattler Tringa brevipes), it also had greyer, more noticeable streaking on the breast, sides and undertail coverts. In flight there was no apparent wing-bar on the upperwings, which was in contrast with the white wing-bars of Curlew Sandpipers. Although the white rump of both species was similar, the toes projected noticeably in flight past the tail tip in the Stilt Sandpiper but it was difficult to see any of the foot of a Curlew Sandpiper. The Stilt Sandpiper was sometimes difficult to pick out quickly, because of its similarity to Curlew Sandpipers. One observer noticed that the mantle feathers of the Stilt Sandpiper were often raised, as if caught in a breeze, whereas those of the Curlew Sandpiper were usually not raised. This later proved to be a quick way of locating the Stilt Sandpiper. During the nearly three months' stay of this wader in the observation area, visits were made by several local and interstate observers. Occasionally up to 20 or more people were present at the same time to view the Stilt Sandpiper and it is probable that nearly 100 saw the bird. Rohan Bugg photographed the bird, although images of it obtained are small (Plate 47) .

Acknowledgements Particular thanks are extended to Robert J. Swindley for his comments on the plumage state of the A val on Stilt Sandpiper, and to Rohan Bugg for allowing the use of his photographs. The efforts of Laurie O'Connor and Geoff Gayner to obtain photographs, unfortunately unsuccessfully, for this paper on the bird are also greatly appreciated.

References Benson, A. (1991), 'Observation of Stilt Sandpiper', Cumberland Bird Observers Club News!. 13(2), 4. Bent, A.C. (1927), life Histories of North American Shorebirds, Part 1, Dover, New York. VOL. 14 (8) DECEMBER 1992 Wattle Colour of Brush-turkey 317

Chandler, R.J. (1989), The Macmillan Field Guide to North Atlantic Shorebirds, Macmillan, London. Cramp, S. & Simmons, K.E.L. (1982), The Birds ofthe Western Palearctic, vol. 3, Oxford University Press, Oxford. Hayman, P., Marchant, J. & Prater, T. (1986), Shorebirds, An Identification Guide to the Waders of the World, Croom Helm, Kent. Johnsgard, P.A. (1981), The Plovers, Sandpipers and Snipes of the World, University of Nebraska Press, Lincoln & London. McKean, J.L. (1981), 'First record of the Stilt Sandpiper from Australasia', Notornis 28, 48. Prater, A.J., Marchant, J.H. & Vuorinen, J. (1977), Guide to the Identification and Ageing ofHolarctic Waders, BTO Guide 17, British Trust for Ornithology. Received 17 July 1991 •