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Hello

This gull I photographed at Hirtshals, Northern Jutland, Denmark, 14/9-2011.

Any comments on the ID of the gull would be appreciated.

Best wishes, Rune

hi rune,

looks like stemming from one of the polish or latvian caspian gull colonies. the bird is quite classic but slightly late in scap moult indicating a more northern origin like e.g. this from 11.09. finland: http://www.tarsiger.com/images/hytpe/11 ... 6P9436.JPG. of course it would be hard to exclude an argentatus parent or grandparent but imo it can go as a pure bird.

cheers

lou

Hi Lou

Thanks

So you think that the underwings are within the variation of Caspian Gull?

Best wishes, Rune

definitely! caspians with dark underwings are the rule e.g. in danube delta. have a look at the birds from 2. and 4.09.2010: http://lou.bertalan.de/gulls/m_grp.php? ... nans%201cy

Somehow not a pure argentatus - or cachinnans for that matter. In flight it seems to have a michahellis tail pattern and the inner primaries shows a pattern similar to michahellis or cachinnans.
Without going in to all the detailes - why not a arg. x cach.

JanJ

I can agree with Jan. Bird very similar to these juv. ringed in mixed colony (arg. x cach), which in my opinion really can be a hybrid of Lar arg & Lar cach.

Michal

For me, this bird is a Herring Gull. A species in which all the shown features fits.

Two more pictures taken by Søren Kristoffersen ca be seen here http://www.pbase.com/nature_pix/image/138212447 and here http://www.pbase.com/nature_pix/image/138212450.

Rune

I am sure, the Hirtshals-gull is an Hybrid HG x CP. The fresh tertial-pattern (dark with broad pale top) is a typical cach-feature. But shape and quite dark underwing belongs more to HG.

I hate this birds. Next year I will personally try to get more information in the Lausitz mixed colony. The local ringer Heiko Michaelis (sic!) calculates 60% pure cach, rest HG and hybrides, only a few YLG. 15 year ago the majority were HG with some CG and YLG.

I agree with Oskar; why not a HG?