Jem's Birding & Ringing Exploits in the Eastern Province and elsewhere in Saudi Arabia
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27 December 2013
Caspian Stonechat – Sabkhat Al Fasl
Whilst birding at Sabkhat Al Fasl I found a very nice
male Caspian Stonechat. The Stonechat complex is as its name suggests is very
complex and a new paper has been written by Lars Svensson, Hadoram Shirihai, Sylke Frahnert &
Edward C. Dickinson on the Taxonomy and nomenclature of the Stonechat complex Saxicola
torquatus sensu lato in the Caspian region. This paper suggests that the mainly Asian form becomes the Eastern Stonechat S.
maurus (Pallas, 1773). This species has several recognised subspecies, with
three occurring in Saudi Arabia as well as being Palearctic taxa: maurus breeding
in Russia and marginally in adjacent parts of eastern Europe, in western and
south-central Siberia, Kazakhstan and parts of Transcaspia, east to north-west
Mongolia and south to Afghanistan and northern Pakistan (possibly also in
north-east Iran); variegatus (S. G. Gmelin, 1774) in eastern Ukraine on the lower
Don, east Crimea, the Kalmykiya plains north-east to the Volga Delta area, in
the south on the northern slopes of Caucasus, apparently reaching north Azerbaijan
(named as ‘NCT’ for ‘North Caspian Taxon’); and armenicus Stegmann, 1935, in north-east Turkey, Caucasus
(apparently at least locally on the southern slopes), Transcaucasia and western
and southern Iran (named as ‘SCT’ for ‘South Caspian Taxon’).
Birds previously known as Caspian Stonechat Saxicola torquatus variegatus are thus now known as
North Caspian Taxon (NCT). The paper states
that the northern population has a very characteristic male plumage with
extensive white portions on each side of the inner tail (between half and
three-quarters of the outer tail feathers white), not unlike the pattern in
many wheatears or male Red-backed Shrike Lanius collurio. This can
clearly be seen in the flight shots of the bird I found at Sabkhat Al Fasl with
the paper saying it can easily be seen on a flying bird, but can be more
difficult to confirm on perched birds with closed tails. The amount of white in
the tail on males is subject to a subtle cline; at its maximum in the Volga
Delta region, becoming slightly more restricted in the south. Both sexes
resemble nominate maurus from further east and north in that they have a
large unstreaked pale rump patch, buffish when fresh, white when abraded and bleached.
In comparison, European Stonechat S. rubicola has a streaked rump with
usually limited white. The NCT male has a concentrated red-brown chest patch
and a large white patch on the neck-sides, again more like nominate maurus and
different from most rubicola which again can be seen on the photogrpahs
of the Sabkhat Al Fasl bird. The NCT female is very similar to females of nominate
maurus and usually can be identified only if handled. The female has much
less white on the base of the rectrices than the male, generally requiring that
the tail-coverts be lifted to reveal the white, and a few females lack any. The
name used for the NCT in Vaurie (1959), Ripley (1964), Urquhart (2002) and
Dickinson (2003) has been variegatus.