24/03/2004
Share 

Focus On: Daurian Jackdaw – Britain next?

2505c85e-e65f-43e6-90f8-2cc358f501bb

Daurian Jackdaw Corvus dauuricus is the eastern equivalent of Eurasian Jackdaw Corvus monedula, with which it forms a superspecies; indeed in the past some authors have 'lumped' the two species. Daurian Jackdaw breeds in southern Siberia from 96°E, eastwards to Amurland and Ussuriland, south through Mongolia and Manchuria to northern and western China. It is a short-distance migrant and winters south to Russian Turkestan, Korea, Japan and southern China. Populations are resident to migratory, with northern breeding areas usually vacated except in mild weather. There is a suggestion that juveniles move further south than adults in the winter.

The identification of Daurian Jackdaw was recently covered by Paul Leader in British Birds. Daurian Jackdaw has three age-related plumages. Juveniles and adults have a pied plumage, whilst first-year birds have a largely black plumage. First-winters can be aged as such by their brownish primaries and brownish pointed rectrices, using the same criteria as for Eurasian Jackdaw. In Western Europe, an adult will look strikingly obvious, but it is likely that some first-winter birds are being overlooked. First-winters can show prominent silvery head streaking after the early winter period, prior to which the head is largely unstreaked. During this late autumn/early winter period identification from Eurasian Jackdaw is tricky but can be achieved through several features: glossy black throat contrasting with the upper breast; dark iris; and dark nape.

Daurian Jackdaw is yet to occur in Britain, but there have been 7 records from elsewhere in western Europe, some of which may have involved the same bird. The records are: Finland (May 1883), Sweden (April 1985), two in the Netherlands (May 1995 and May 1997), France (June 1995) and Denmark (April 1997). The 1995 and 1997 records might have related to just two birds, or perhaps even the same bird picked up in different years? All have been distinctive adults in pied plumage and all have been in spring, an occurrence pattern unique for 'sibe' passerines in Europe, but one that might be explained by first-winters being overlooked during their arrival in western Europe and being identified when they are present in their conspicuous adult plumage. As with many species, the escape possibility looms, but if these records involved escapees it would be expected that the European occurrence dates would be evenly distributed throughout the year. It is perhaps more likely that these birds are genuine vagrants that have arrived during the autumn and have gone undetected in the interim due to their nondescript plumage and birders' lack of attention to corvid flocks.

Content continues after advertisements

Given that the autumn of 2003 was superb for the range and number of 'sibes', might the first addition to the British list of 2004 be a pied spring bird on the east coast?

Below are images of the species taken in Japan. As can be seen from the photos, pied adults are quite distinctive. However, 1st-winter birds could easily be overlooked amongst their congeners in a European setting. The bird with a deformed upper mandible might struggle to make it past the rarities committee, but illustrates that even wild birds can have deformities!

Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson) Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson)

Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson) Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson)

Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson) Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson)

Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson) Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson)

Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson) Daurian Jackdaw: Kyoto, Japan - Jan 2004. (Photo: Neil Davidson)

Eurasian Jackdaw: Fairhaven, Lancs. - Jan. (Photo: Sue Tranter) Eurasian Jackdaw: Fairhaven, Lancs. - Feb. (Photo: Sue Tranter)

References

Leader, P J. 2003. 'Identification of Daurian Jackdaw.' British Birds 96:520-523.
Cramp, S., and Perrins, C. M. (eds) 1994. The Birds of the Western Palearctic. Volume 8. OUP Oxford.
Madge, S., and Burn, H. 1994. Crows and Jays. Christopher Helm, London.
Written by: Russell Slack