Thursday, 16 February 2012

Iceland Gull (Larus glaucoides), 3cy, 5.2.2012, Roshage, Hanstholm #4

This is the fourth of eight white-winged gulls found in the Hanstholm Harbour area in just one day, with six Kumlien's /Iceland Gull-types and one 2cy and one 3cy Glaucous Gull.

It has been identified as a Kumlien's Gull by people who have seen it under much better circumstances than illustrated in these photos, but based on my personal view a heavily pigmented Iceland Gull cannot be ruled out. It appears as if the pigmentation is darker on the inner primaries than the outer, i.e. it lacks the Thayer's Gull impression on the outer five primaries. Here are six much better photos of the same individual taken two weeks before on January 21: one, two, three, four, five and six.

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 these 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 just a trait of immature plumage.

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