Mystery Photographs
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Mystery photographs "| /\Q Last month's four pipit photographs (repeated here as plates A \j*j 37-40) were taken by Dr Klaus Robin in Switzerland, where the bird was present for several days in December/January 1982/83. They are selected from a series of 12 black-and-white prints sent to the Rarities Committee by Dr Roland Luder for an opinion on the identity of the bird. 34 [Bril. Birds 79: 34-39, January 1986] Mystery photographs 35 37-40. Mystery photographs 109 (Klaus Robin) Brief accompanying notes referred to a cream-coloured breast, rather yellowish-brown upperparts, flesh-coloured legs, and a call resembling that of Dunnock Prunella modularis or Reed Bunting Emberiza schoeniclns. The choice was between Meadow Pipit Anthus pratensis and Red-throated Pipit A. cervinus in one of its non red-throated plumages. There was strong initial opinion that it was a Red-throated Pipit (9:1 in favour on the first circula tion). The eventual clear majority view, however, was for Meadow Pipit: including the opinions of three international experts also consulted, the final votes were ten for Meadow, one for Red-throated (an unrepentant JTRS), and two undecided. It must be said at the outset that the severity of the problem set here is rather artificial. In the real field situation, Red-throated Pipit is almost always first identified by its flight call, which when heard fully is to some ears among the most distinctive of all bird noises: a very high-pitched, penetrating 'psssss', which starts emphatically and trails off to an almost inaudible finish, lasting a full half-second. Some observers apparently have trouble in distinguishing the call from that of Olive-backed Pipit A hodgsoni or Tree Pipit A. trivialis {Brit. Birds 73: 233; 74: 228-229), but at least it's quite unlike the short, squeaky notes of Meadow Pipit. The Dunnock- or Reed Bunting-like call described for this bird does not help: which of the varied calls of these species did it resemble? With a stretched imagination, this imprecise description could fit either Red-throated or Meadow. In the field, differences in colour tones would also be helpful. Red- throated always lacks Meadow's usually obvious yellowish-olive tones on the upperparts and ear-coverts, and is instead generally greyish, greyish- brown or obviously brownish-toned in these areas, much depending on the light. The 'rather yellowish-brown' upperparts noted for the mystery bird 36 Mystery photographs 41. Meadow Pipit Anlhuspratcnsis, Netherlands, April 1983 (ArnoudB. van den Berg) therefore seems to be a clear point in favour of Meadow. Also, the colour of the pale markings on the upperparts and wings, and—especially—the base-colour on the flanks and breast of Red-throated is usually obviously creamier or whiter than that of Meadow, which is usually pale buffy-yellow in these areas. The infrequent 'grey-and-white morph' Meadow Pipits (which may be familiar to observers who search pipit flocks in autumn: on Scilly, for example, something like one in 200 is of this type) can look like Red-throateds in these respects, however, with the result that it would take the sharpest of observers confidently to claim a Red-throated without hearing the call or seeing the diagnostic finely streaked rump (plain on Meadow). The mystery bird unhelpfully managed to keep its rump hidden in the whole 12-print series, but the 'cream-coloured breast' seems to be a contradictory point in favour of Red-throated. As an aside, it would be interesting to know what these 'grey-and-white morph' Meadow Pipits are. Perhaps the coloration is age-related, or that of a particular geographic population, or (in my view most likely) just the extreme of a cline of colour variation. In addition, Red-throated tends to look slightly heavier and shorter-tailed (especially in flight), like Tree Pipit, and Meadow has a very short projection of primaries beyond the tertials, which is tiny or lacking on Red-throated (plate 39 seems to show a Meadow-like wing-structure, but it is debatable). So, for silent, 'rumpless' birds (or black-and-white photographs) the best Mystery photographs 37 clinchers probably lie in the following differences in plumage patterns and tones: HEAD Differences are sometimes slight, but Red-throated tends to show a more darkly streaked crown, longer and more defined supercilium, more uniformly dark ear-coverts, bolder and 'cleaner' pale submoustachial stripe, and malar stripe ending in a larger dark patch at sides of lower throat. UPPERPARTS Red-throated shows pale stripes or 'tramlines' at the sides of the mantle, but, because they are whiter and are outlined with blackish stripes, they are more contrasting and obvious than the similar marks shown by many Meadow Pipits. The centres of the wing-coverts and tertials are darker, giving slightly greater contrast with the whiter fringes than is the case with Meadow. 42. Red-throated Pipit Anlhus cervinus, Kenya, February 1973 (J. F. Reynolds) 38 Mystery photographs UNDERPARTS The breast-streaking on Red-throated is more strongly con trasting, better-defined, slightly bolder and—most important—more con tinuous than on Meadow, giving a more striped, less streaked appearance. On Red-throated, the breast-streaking usually extends down the full length of the flanks at the same strength (usually showing as two bold, black stripes), whereas on Meadow the flank-streaking is thinner and more broken than the streaking on its breast. The mystery bird's head pattern is better for Meadow, with subdued supercilium which also gives greater contrast to a pale eye-ring, and rather pale-centred ear-coverts. Allowing for photographic effects which can exaggerate contrasts, the mantle, wing-covert and tertial patterns of the mystery bird also seem well within the range of Meadow. Allowing for the fluffed-out breast-feathers in some photographs (e.g. plate 39), which exaggerates the thickness of the streaks, the breast does not seem suffi ciently boldly striped for a Red-throated; indeed, plate 40 (in which the breast-feathers are sleeked down) shows an unremarkable, Meadow-like pattern. On the flanks, the streaking is clearly thinner and more broken than on the breast, and does not show as two bold stripes (although caution is clearly necessary over how the feathers lie and how much of the flanks are concealed under the wing), and this is perhaps the strongest single pro- Meadow feature in the photographs. The Rarities Committee thanks Dr Luder for posing this hopefully instructive problem, and Per Alstrom, Jon Dunn and Killian Mullarney for their valued comments. PJG 43. Red-throated Pipit Anlhus cervinus, Kenya, February 1973 (/. F. Reynolds) Mystery photographs 39 44. Meadow Pipit Anthuspratensis, Dumfriesshire, summer 1975 (Robert T. Smith) 45. Mystery photograph 110. Identify the species. Answer next month .