Tuesday, 8 July 2014

Possible Kumlien's Gull (Larus [glaucoides] kumlieni), 4cy, 03.02.2012, Aabenraa Harbour

Case: 2013-167 (also 2013-163)
Date: 2012-02-03
Site: Aabenraa Harbour, Denmark
Observer: *Clemens Portofeé, Martin Gottschling

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 faint pigmentation along the tip of the outer primaries; however, the flight shots do not seem to show 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: 3.2.2012. Foto: Martin Gottschling
Date: 3.2.2012. Foto: Martin Gottschling

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