Wednesday 9 July 2014

Possible Kumlien's Gull (Larus [glaucoides] kumlieni), 4cy, 28.01.2012, Thorsminde Harbour

Case: 2013-164
Date: 2012-01-28
Site: Thorsminde Harbour, Denmark
Observer: *Allan Kjær Villesen, Jørgen Nissen

From these photos alone it seems not safe to exclude a well-marked Iceland Gull (Larus glaucoides) though this is not to say it is not Kumlien's Gulls. It has without doubt some dark pigmentation along the tip of the outer primaries, but as photos of the open wing are missing it is not possible to determine whether is has a clear Kumlien's/Thayer's pattern on the outer primaries. Note that it is not abnormal for 2nd- and, especially, 3rd-cycle glaucoides to show a brown wash on the outer primaries. The plumage of such well-marked immature gulls often looks quite retarded, with still lots of brown in the wing. Note that the brown wash on outer primaries of such birds simply matches the brown wash on outer secondaries, as is often the case in other 3rd-cycle gulls (e.g. Herring Gull). It is therefore considered just to be a trait of immature plumage.

Date: 28.1.2012. Foto: Allan Kjær Villesen
Date: 28.1.2012. Foto: Allan Kjær Villesen
Date: 28.1.2012. Foto: Allan Kjær Villesen
Date: 28.1.2012. Foto: Jørgen Nissen
Date: 28.1.2012. Foto: Jørgen Nissen
Date: 28.1.2012. Foto: Jørgen Nissen

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