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Case Summary for:
Submission No 213: Purple-backed (Daurian) Starling Sturnus sturninus, Christmas Island. 4 June 1996. Submitted by Richard Hill. Verdict: Accepted This submission concerns a record of a starling reported from Silver City, Christmas Island on 4 June 1996. The initial find was reported to a local ornithologist who was subsequently able to view the bird, take note of important features and compare with available literature (Mackinnon & Phillips 1993 and King et al. 1984) jointly with the finders. The bird was observed in vegetation along a garden fence-line. The description provided outlines a light grey bird approximately 18cm in length. The head and body appeared very sleek with a short tail. A dark eye was clearly visible and a thin white ring could be seen around the outer edge. The upperparts revealed a distinct white bar extending to form a V across the back along with some secondary barring. The leading primaries appeared glossy black, being iridescent green in sunlight. The underside was very pale grey with a buff colouration to the vent. There was a dark mark on the nape that was first thought to be shadow and later confirmed to be a distinct dark patch. Legs grey in colour with a notable long tarsus. Although the description contains a few technical inaccuracies (e.g. the white V-mark is formed by the scapulars and is not a true wing bar) and makes no mention of either the buff rump or the panel in the folded remiges (Lewington et al 1991), the observers have clearly noted most of the major characters that, taken together, are diagnostic of a first-year or adult male Purple-backed (or Daurian) Starling. The field sketches are a valuable adjunct to the brief though more than adequate description; and the fact that the original observers were able to obtain corroboration from a third observer and check identification with relevant field guides further serve to make for an acceptable Australian first. The illustrations in Lewington et al. (1991) suggest that the combination of a black nape mark, blackish ‘back’ and blackish primaries with distinct green iridescence fits only a male in either adult, first-winter or first summer plumage. In the same plumages females are much browner above and about the head, having a warm-brown ‘back’ (mantle and inner scapulars) and lacking the dark nape-patch and green iridescence in the remiges. Lewington et al. further note that first-winter birds are like the adult of its respective sex, but differ in usually retaining some distinctive juvenile wing feathers; the outermost tertial and the innermost c. four secondaries, these being brownish and distinctly pale-fringed and contrasting with the darker remaining remiges. They further state that these feathers are normally moulted in late (i.e. N hemisphere) winter, so that first-summer males are usually indistinguishable from the adult male. It is also worth noting that Daurian Starling is a fairly long distant migrant in East Asia. It breeds in Russia (Transbaikalia region to S. Amur regions) and South to China (Manchuria) and Korea. Over-wintering in lowland areas of Malaysia and Indonesia from October to April (Van Marle & Voous 1988, Lewington et al. 1991). On Sumatra, the species is reported to frequent open country, rice fields, gardens and other cultivation and is often recorded in villages and towns (Van Marle & Voous loc.cit.). It is also listed by Andrew (1992) as occurring on Java. Its occurrence on Christmas Island is therefore not unsurprising. The species is also established as a long-distance vagrant, with at least two accepted records from the Western Palearctic (Lewington et al., Riddiford et al. 1989). The committee has no reservation in accepting this record as a first-year or adult male Purple-backed (Daurian) Starling.
References and Bibliography
Tony Palliser |