Heuglin's Gull (L. heuglini / antelius)
Amir Ben Dov (Israel)
Chris Gibbins (Scotland)
Hannu Koskinen (Finland)
Mars Muusse (the Netherlands)
3cy heuglini: December
Below you will find a copy of Descriptive update on gull taxonomy: 'West Siberian Gull', by Valery A. Buzun published in British Birds 95 • May 2002 • 216-232. Most of the text below is a copy of that article, but now illustrated with many more birds and figures, and additional data from Dutch samples.
"I" in the text below refers to the original author Buzun. If any errors occur in this text, please let me know and mail to marsmuusseatgmaildotcom.
Descriptive update on gull taxonomy: 'West Siberian Gull' - Valery A. Buzun
Geographical variation in antelius
It follows from table 4 that variation in wing length from east to west is simply an artefact of small sample size. When the sexes are combined for samples from Kanin and Russkii Zavorot, all the differences are not significant (Wilcoxon t-test). There are no significant tendencies for weight and other body-size parameters to increase towards the eastern end of the breeding range. If clinal size variation exists, the trends are extremely weak.
References - See PDF
[Additional, Mars Muusse: some Lesser Black-backed Gulls have been recorded in (eastern and central ) Europe in winter, still growing outer primaries by January or February. The possibility to identify such birds as heuglini is discussed HERE.
Nesting adult and nest site (below) of 'West Siberian Gulls' Larus heuglini antelius, Russkii Zavorot peninsula, Malozemel'skaya Tundra, Russia, June 1996. Concealment of nests is not typical, but some pairs nesting on mainland tundra use willows Salix arctica or S. glauca to shelter the nest. For details, see Buzun (in press).The callipers in plate below show 10 cm.
General clues for ageing 3cy heuglini in fresh third winter plumage
3cy heuglini in November-December normally show a plumage very much similar to adult birds. A variable number of immature features may still be possible, but best clue to age this group probably is the presence of broad dark centres of the greater primary coverts. Small, sharply defined centres on slate grey feathers probably is possible in full adults as well, but when the centres are broad brownish-black and the tips of these greater primary coverts are pale whitish, this may be good indication for 3cy birds. Furthermore, black may still be apparent in the rectrices, some brown wash may be visible on some wing-coverts and the bill-band may be obviously broad in third winter birds.
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