A NOTE ON FIELD-IDENTIFICATION OF By P. J. HAYMAN (Plate 44) R. MEINERTZHAGEN ( of Arabia, p. 474) has shown that specimens exist which are intermediate between the ( p. pratincola) and the Black-winged Pratincole (Glareola nordmanni). The latter which is dominant in S.E. and S.W. Asia is considered to be a colour phase of G. p. pratincola. I have not seen any of these intermediate birds either in the hand or in the field and the following discussion refers to typical birds of both forms. Most observers, when first seeing a pratincole, invariably look for the colour of the under wing-coverts, but these are often difficult to determine, especially in G. p. pratincola as the red colour becomes lost in the shadow of the wing. The pattern of the upper-parts is in fact a surer guide to specific identification in flight. Once aware of the differences between the two forms, I have had no trouble in separating them in the field. Features common to both forms in summer and winter, i.e. head-pattern, under-parts, rump and tail, black legs and the white shaft of the second primary, which have no direct bearing on identification, are omitted in the following notes. PRATINCOLE Upper-parts : In flight this form shows a strongly contrasting wing-pattern (drawing, plate 44), whereas the Black-winged form has almost uniform upper-parts. Inner primaries and outer secondaries are pale, forming a break in the dark areas of the wing. All secondaries have a white trailing edge which is emphasized by being seen against the dark inner secondaries. Under-parts : In flight, directly overhead, the under-sides of the wings look extremely dark, much more so than one would expect. If a bird is held in the hand and the wing viewed through half-closed eyes the red-brown colour of the axillaries and coverts will be seen to have almost the same tonal value as the grey-brown feathers surrounding it—hence the difficulty in picking out this feature in the field. Generally the red-brown under wing-coverts can only be picked out in the best light conditions, or especially when caught by a setting sun, when they are clearly visible over 300 yards away. [Also often on take-off.—P.A.D.H.]. The markings of the upper-parts are the best guide to this form (if the colour of the under wing-coverts is not visible) ; particular emphasis should be placed on the contrasting wing-pattern and, if it can be seen, the white trailing edge to the secondaries. BLACK-WINGED PRATINCOLE

312 VOL. XLIX] PRATINCOLE RECOGNITION 313 When I first saw birds of this form, I was surprised at their "black-and-white" appearance which is enhanced in dull weather. Upper-parts : Upper-parts have a marked green tinge. At close range the darker primaries and secondaries show up fairly well against the rest of the wing, but this distinction is largely lost at longer range. There is no white trailing edge to the secondaries. The rump shows up very well and is much more obvious than in the Pratincole. Under-parts : The black of the under wing-coverts is striking, especially in bright weather and can easily be seen at a reasonable range. But if an observer is not familiar with relative under-wing shades of the two forms, this feature as a sole means of identifi­ cation (unless noted beyond reasonable doubt) should be used with caution. Almost uniform upper-parts, jet black under wing-coverts, lack of a white trailing edge to the secondaries and pied appearance in the field distinguish this form from the Pratincole. On nth September 1954, I saw a mixed party of nine adult and juvenile birds (G. nordmanni), all in winter plumage, at Kabrit in the Suez Canal Zone. Most adults had streaked breasts and a few had marked pectoral bands; one bird showing a distinct pink suffusion below the pectoral band. The leg colour of some birds was noted as grey-black, but I have an entry in my field note­ book which states that "legs look pale yellowish and trail as the birds take off". When approached, the birds stretched their wings above their backs for a few seconds and flicked their tails down suddenly when nervous. Photographs of Pratincoles at the nest in the Camargue (France) have been published in British Birds (vol. xli, plates 47-51). PLATE 44

Drawn by P. ]. Hayman (Upper) PRATINCOLE (Glareola pratincola) (Lower) BLACK-WINGED PRATINCOLE (Glareola nordmanni) _, sketches are designed to show that there are more striking differences in the field between typical specimens of the two species than the colour of the under-wing, which is often difficult to determine. The Pratincole has a strongly contrasting wing-pattern with pale inner primaries and secondaries, and a white trailing edge to the latter. The Black-winged has more uniformly dark upper-parts which contrast more with the rump, while the whole bird has a more black-and-white appearance (see page 312).