sunnuntai 17. joulukuuta 2017

Harmaata vain - Too many shades of grey - a Steppe Grey Shrike in Arava in 26th Oct 2017

Pitkästä aikaa lyhyt päivitys ei harmaiden päivien, vaan harmaiden lanttujen inspiroimana :)

Finally had some time to sort out a few pics. Birding in Eilat and Arava area is absolutely fun, even in October, when migration is perhaps not the most intense and many wintering birds are still on their way to south. Some birds are around in good numbers, and the best of all, one can stumble upon a good one practically anywhere, anytime!

This stunner, a first-winter Steppe Grey Shrike, was perching on a traffic sign near Arava junction, exactly here: 30.8555556,35.2611111

Steppe Grey Shrike Lanius pallidirostris, 1st winter

Steppe Grey Shrike Lanius pallidirostris, 1st winter

Steppe Grey Shrike Lanius pallidirostris, 1st winter
Compared to local Great Shrikes, namely Southern Grey Shrike ssp. elegans, this pale steppe form is very different in many respects. Of course it is a young bird, in the most striking of all plumages. Pale sandy-cream overall, isolated dark patch on ear-coverts, pale lores, stubby pale bill, long primary projection and a large white wing patch restricted to primaries only are classic field marks.

Lanius aucheri/elegans, or whatever, from Nizzana, Israel
The taxonomy of Great Grey Shrike complex is a rapidly evolving one, as is their field identification.

For example, the IOC gives Steppe Grey Shrike a specific status, Lanius pallidirostris, split from Southern Grey Shrike Lanius meridionalis; the HBW/BirdLife treats it (as well as other forms) a subspecies of Great Grey Shrike Lanius excubitor pallidirostris, while Dutch committee for avian systematics CSNA places it under name Steppe Grey Shrike Lanius lahtora pallidirostris. Compared to other bodies, the CSNA is not applying Biological Species Concept, but uses phylogenetic approach, thus recognising species in relation to their evolutionary history.

Local Finnish early winter specimen of Northern Great Grey Shrike Lanius excubitor
The Nordic rarities committees cooperated and made an extensive study reviewing variation of nominate and homeyeri -type Great Grey Shrikes in 2016. The dire conclusion was that all classical field marks of homeyeri can be found on specimens within breeding range of nominate excubitor. It is not possible to ID homeyeri on a vagrant context, and conclusively, all previously accepted records of homeyeri were rejected.

Well, borealis/sibiricus is still there...





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