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Lokalitet:
Langano - Etiopien
2011-12-23
Fotograf: Thomas Varto Nielsen - Se profil

Titel: 1cy / 1st winter

Beskrivelse: Dokumentationsfoto. Iflg. "Gulls" skulle det være næsten umuligt at kende ung Fuscus fra ung Heuglini, Således står der under juvenil Heuglini: "most are inseparable on the basis of plumage alone". Ganske rigtigt ser jeg af og til ungfugle/1. vinter som dragtmæssigt ligner en mellemting. Men jeg ser også fugle som den på billedet her, med Lysere (mere grå) ryg og lysere undervinger end Fuscus. Og har de så tilmed lidt svartbag over sig, især næbbet, kommer de i notesbogen som Heuglini. Men det kan jo sagtens være jeg tager fejl og kommentarer er derfor meget velkomne. Jeg oploader dette ringe foto netop for at finde ud af om jeg er på rette spor ang ID af Sildemågerne i Etiopien. Jeg kan iovrigt ikke finde billeder af ung Heuglini i netfugls galleri. Jeg kan oplyse om Silde/Solvmåge komplekset i Etiopien at: Langt den almindeligste er Fuscus, derefter kommer Heuglini som er fåtallig vintergæst. Disse er de eneste to der med sikkerhed forekommer (der ses også adulte Heuglini). Cachinnans og Barabensis er rapporteret flere gange og forekommer formentlig, men jeg har aldrig set fotodokumentation og har heller ingen sikre egne obs. Desuden er Taimyrensis, Armensk Måge og sågar Argentatus (!) rapporteret, men der er vist ingen dokumentation. Det er dog sandsynligt at nogle af disse forekommer, især Taimyrensis er flere gange meldt herfra. Og kan man så egentlig udelukke at fuglen på billedet er en Taimyrensis? I så fald burde et "tvivl om bestemmelsen" måske tilfojes dette billede. Generelt ser man ret få store måger og de er ofte ret sky, så der er ikke helt ligetil at få styr på dem.

Uploadet 2012-02-17 Publiceret 2012-02-17 Larus fuscus heuglini Lesser Black-backed Gull
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Kommentarer
Jan Jörgensen
19. feb. 2012 kl. 00:26
Hi Thomas. There´s no real reason - or should we say - safe reason to consider that your 1st winter birds are 'taymyrensis' (we wouldn´t know how to identify them anyway due to similarities to fuscus/heuglini. There seems to be no real proof for this invalid taxon (Yésou 2002)to occur in the area. Any such claims probably refers to heuglini/barabensis. Much left to be said about this problematics. taimyrensis and here Since both fuscus (Baltic) and heuglini occur in Ethiopia it could be anyone of these. Judging from the pic above there might be structural reasons for heuglini, seems a bit heavy with a large bill for Baltic fuscus, not taking sexual variation into the equation though. Then again, how can we be sure from a couple of flight pic and for that matter, in real life. I can´t think of any fullproof reason for a safe identification of heuglini or Baltic fuscus in a case like this. There´s some good stuff here JanJ
Thomas Varto Nielsen
20. feb. 2012 kl. 18:04
Hi Jan Thank you very much for comment and very useful links! Regarding the structure of this particular bird. It was seen in the same area for several days along with about 15 Fuscus (1cy, 2cy and adults). It was always easy to find, even though it was mostly seen at great distance. The plumage fits Heuglini and also the structure - directly compared with Fuscus. That's why I chose photos of this bird. But if even this one can't be safely identified , then it is really difficult!
Jan Jörgensen
20. feb. 2012 kl. 20:55
After looking again, my suggested - on structure and bill size - heuglini is probably not an entierly bad suggestion, it might even be the correct id for this bird. With your descriptio and in direct comparison with Baltic fuscus it could well be. However from where I stand with these pic I´m going to play safe. Some Baltic fuscus can show underwing pattern similar to yours, as can be seen here (although taken in Oct). Have a look at some juv/1st winter heuglini types here and notice the variability both structurally and moult of scapulars. Wonder what Klaus might have to say? JanJ
Klaus Malling Olsen
20. feb. 2012 kl. 21:26
I have a strong heuglini-feeling on this bird. Allthough fuscus and heuglini plumagewise may be so similar as to be called identical, this bird definately shows too strong bill for even the largest fuscus; bill and head in such large birds often recalls Yellow-legged or even Greater Black-backed Gull. Thomas have seen the bird together with fuscus and noted the differences, this adds to its ID as a heuglini.
Knud N. Flensted
20. feb. 2012 kl. 22:54
I agree very much in L. heuglini. Same arguments as Klaus mentions :-)

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