Isabelline Shrike
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HANDBOOK OF WESTERN PALEARCTIC BIRDS SHRIKES of all-dark lores even in breeding a (a few exceptions noted, rump/uppertail-coverts. Adult o Red-backed Shrike gener- though, displaying a complete mask), and have on average ally separated by ear-coverts and back being warm brown, ISABELLINE SHRIKE paler sand-brown upperparts and paler brown wings (tertials often tinged rufous, and nape and sides of neck tinged grey Lanius isabellinus Hemprich & Ehrenberg, 1833 especially are paler brown compared to isabellinus). Uppertail (Isabelline has darker brown-grey ear-coverts and more is on average slightly paler and less vivid rufous. Sexes differ uniform grey-brown upperparts, lacking contrasting grey in the same way as in isabellinus, only less obviously, and nape), longer primary projection and shorter tail. The tail is Fr. – Pie-grièche isabelle; Ger. – Isabellwürger some are difficult to sex. Ssp. arenarius has smaller white darker, less rufous-tinged, above and paler greyish-white or Sp. – Alcaudón isabel; Swe. – Isabellatörnskata primary patch, which can be entirely hidden by coverts, and cream-coloured, less russet-tinged, below. However, a very The Isabelline Shrike breeds mainly in Mongolia and is the smallest of the three. – Note that numerous birds few have confusingly similar tail-colour, both species being China, east of the closely related Turkestan Shrike, appear intermediate between arenarius, tsaidamensis and rather similarly rufous-tinged. In such cases, often helpful to isabellinus, being difficult to label subspecifically away from note precise pattern of outer tail-feathers, these having dark a species with which it has often been lumped in breeding ranges. subterminal bars but only very tips paler (Red-backed: more the past. However, here these two are regarded as extensive dark subterminal bars and well-marked cream- VOCALISATIONS Resemble those of Red-backed and separate species, and at least adult aa usually white edges to distal parts of tail-feathers, especially on outer Brown Shrikes. Alternative song, or ‘advertising call’, a differ rather clearly. It occupies similarly dry and webs). – Note that Isabelline and Red-backed are known repeated harsh, loud zech or vehv from prominent perch. In to fairly frequently hybridise locally in Central Asia, further warm habitats as the Turkestan Shrike, being alarm a drawn-out series of harsh notes, tsche-tsche-tsche- complicating matters. – First-winter Isabelline resembles commonly found in deserts and semi-deserts, tsche-tsche-… (BWP). Has similar prolonged warbling sub- first-winter Brown Shrike, but latter differs structurally from preferably along rivers and on mountain slopes. It song full of mimicry as Red-backed. Isabelline in somewhat larger head, heavier bill and narrower is a summer visitor, wintering further south, from E and more graduated tail, although the difference in size of L. i. isabellinus, o, presumed ad, Greece, Mar: a moderately SIMILAR SPECIES Strongly resembles Turkestan Shrike, Africa to NW India. marked o in terms of barring but has quite warm orange-buff especially in o and immature plumages; see Identifica- head and bill can be very slight in relation to ssp. cristatus, body-sides (unlike o Turkestan Shrike, which is usually more tion and under Turkestan Shrike for details. – First-winter the race of Brown most likely to occur in W Europe. Brown L. i. isabellinus, a, presumed 1stS, Kuwait, Mar: moult contrast heavily barred and whiter below). Being o, the rather large Isabelline Shrike resembles adult o Red-backed Shrike, is generally darker and more rufous above with more dark outside breeding. – Adult a isabellinus differs from Turke- white primary patch indicates an ad; all visible wing-feathers, in tertials and inner primaries, possibly also in greater coverts, in both being dull or warm brown above, with any fine barring barring retained longer into first autumn (thereby resem- stan Shrike by combination of less rufous-tinged crown/nape spring seems to indicate a 1stS bird, but an aberrantly moulting including primary-coverts, are ad-type (1stS often retains some juv feathers). (L. Stavrakis) on upperparts usually restricted to crown, scapulars and bling Red-backed more than Isabelline), and has solidly (none or just a little, mainly on crown), an indistinct and often ad can perhaps not be conclusively excluded. Note very dark bill and black mask typical of a. Some aa can be rather pure grey buff- or pink-tinged supercilium that does not reach fore- above. (A. Halley) head (except sometimes as a diffuse flush), and on average narrower black mask in its forepart, only rarely extending a Turkestan Shrike). Sexes rather similar, more so than in above nostrils and thinly onto forehead. Further, it has much Turkestan Shrike, but o has at least some faint dark barring warmer pinkish-buff or ochre-buff tinge over entire under- on breast, and an incomplete mask, lores being partly pale; parts, including faintly on throat and centre of breast (where blackish bill commonly has paler base to lower mandible. A typical Turkestan is white). Primaries are rather dark, often very few more resemble Turkestan Shrike and are difficult to equally dark as Turkestan Shrike. White primary patch small identify, having a narrow but rather more whitish supercilium to medium-large. Bill often all black, but at least some have and more rufous on crown and nape. – Adult arenarius and a slightly paler base to lower mandible (not seen in breeding tsaidamensis resemble isabellinus but usually differ by lack L. i. isabellinus, a, Mongolia, Jun: jet-black mask and no trace of bars on body-sides infer sex. Unlike Turkestan Shrike, has more indistinct and often buff- or rufous-tinged supercilium, less or no rufous on crown and nape, and sometimes shorter and narrower mask that either reaches bill or only marginally extends to lores and forehead. Warmer below with ochre-buff tinge, including faintly on throat and central breast (where typical Turkestan is white). Such warmer aa often have less pure grey upperparts. (H. Shirihai) IDENTIFICATION Although geographically somewhat variable, this is generally a greyish-brown and buff-white bird with a dark mask and a rufous-tinged uppertail. Size same as, or subtly larger than Red-backed Shrike, with proportionately somewhat longer tail. Of the three subspecies, one is thought to occur more regularly within the treated region (isabellinus; breeds mainly in Mongolia and adjacent areas, wintering in S Uzbekistan, Turkmenistan, Middle East and Arabia, with a few reaching NE Africa), whereas the other two are believed to be winter visitors only to S Iraq and S Iran outside main wintering area in Pakistan and India (arenarius and tsaidamensis; breed o Isabelline (top left: Mongolia, Jun), Turkestan (top right: Kuwait, Apr), Red-backed (bottom left: England, May) and Brown Shrikes (bottom right: Russia, May): first note that Isabelline and Turkestan in easternmost Central Asia and W China). Identification is usually show stronger contrast between rusty-red tail and rump and duller mantle, and nearly always have diagnostic white primary patch. Isabelline further separated from Turkestan by sandier (less a o aa hampered by a lack of knowledge of plumage variation of L. i. isabellinus, (top) and , Russia, May: some are quite pale below, with rusty-orange concentrated on flanks, and upperparts greyish-brown) upperparts, poorly defined but warmer pale supercilium and warmer underparts with less barring at sides. o Red-backed shows rich brown-tinged rufous upperparts, greyish rump and rather pure grey. Black mask on this a complete (including lores), a normal and common pattern of this race. o invariably has at least neck-sides, darker uppertail and heavy barring below, but no white primary patch; it also has the longest primary projection. Typical for o Red-backed is also reddish mask (the others have darker mask). other than adult aa of both Isabelline and Turkestan Shrikes, some faint dark barring on breast. Ear-coverts dark grey-brown but lores mostly pale and unmarked. There is a good deal of individual Brown Shrike is rather similar to Red-backed, but note larger head, narrow and deeply graduated tail (though not visible here), short primary projection, and darker and more complete mask. (Top left: and incomplete information concerning normal ranges variation in plumage colours and patterns. (E. N. Panov) H. Shirihai; top right: A. Al-Sirhan; bottom left: R. Ridley; bottom right: M. Hellström) — 178 — — 179 —.