Photo Index

Red-backed Shrike Lanius collurio Form kobylini or collurio / phoenicuroides intergrade

Its general characters were as Red-backed Shrike (though it gave the impression of being slightly larger and longer-tailed). However, it differed significantly in the following characters:

(a) brown wing-coverts and back, entirely lacking bright chestnut or rusty hue of typical collurio;
(b) grey of crown suffusing well down onto mantle;
(c) a prominent white patch at the base of the primaries.

Following authors such as Dementiev & Gladkov ('Birds of the Soviet Union'), these characters would equate with kobylini (though kobylini is described as being marginally smaller than collurio). The form kobylini is variously regarded as a subspecies of Red-backed Shrike (Lanius collurio kobylini) or as an intergrade between collurio and Isabelline Shrike Lanius isabellinus of the subspecies phoenicuroides.

As in the Taukum bird, kobylini has browner upperparts than collurio and the grey of the crown extends further down onto the mantle. It tends to show a white primary patch more frequently than in nominate collurio (where such a feature is rare – there is some white at the base of the primaries in the nominate form but it is generally hidden beneath the overlying primary coverts). The breeding range of kobylini encompasses north-west Asia Minor and Crimea.

Although there is considerable individual variation within Red-backed Shrike, Lars Svensson (in litt) does not currently regard this as equating with definable geographical forms. He is now inclined to treat Red-backed Shrike as monotypic, and not to recognise kobylini (or pallidifrons) as valid races. If this view were followed, then the features of the Taukum shrike would be firmly assigned to ingression of phoenicuroides genes into a collurio population.

Of kobylini BWP7 also states: ‘Characters of kobylini probably due to gene flow from Lanius isabellinus phoenicuroides  …’.

Although there was no rufous in the plumage of the Taukum shrike, and the tail was crisply black-and-white, a kobylini-style intergrade between collurio and phoenicuroides appears to be the most likely origin.

In his study of Palearctic shrikes ('Die Würger der Paläarktis'), Panov (1983) illustrated a variety of individuals deemed to be hybrids between Red-backed and Isabelline Shrikes. His illustrations are black and white sketches, with colours indicated by various types of hatching, so precise ‘colour matching’ is difficult. However, one of his sketches appears to show a collurio-like bird with more extensive grey on the upperparts and with white primary patches, and this is labelled as 'velizhanini'. Current studies suggest that there is a whole range of intermediate birds in the region of overlap between collurio and phoenicuroides, and that they cannot be assigned to a few discrete ‘types’.