Simon Rix (writing www.oslobirder.blogspot.com) took a trip to Marienlyst today, trying to locate the Med Gull (something he succeeded with). He looked through the Common Gulls present, and found this one:
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| Photo: Simon Rix |
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| Photo: Simon Rix |
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| Photo: Simon Rix |
A very dark Common Gull. After some reading I found the text about first winter Larus canus kamtschatschensis in Olsen and Larssons "Gulls" very interesting. "Compared to canus and heinei darker and more grayish-brown with extensive streaks". Already here it looks good. An it continuous. "Flanks often extensively dark-spotted or barred, together with breast-sides and upper belly". Later it stands stuff like: "Paler forehead, chin and throat", "Undertail coverts white with extensive Vs", "Lesser and median coverts with triangular dark centres and pale edges", "Underwing have broader dark tips", "Broad, dark tail-bar", "Broader white tail tip than in canus/heinei", and "Bill pinkish, but pink frequently dulled by grey". (Not all of them direct quotes)
What to think about the bird? Hard to say. Canus has a huge variation, and to claim a kamtschatschensis in Norway, when it should has been on its way from Japan to the most east of Sibir and Russia, seems quite a challenge. Maybe they are distinguishable by DNA? The ringing group always want to get their hands on interesting birds!
Hi Sindre,
SvarSlettI also considered kamtschatschensis but according to BWP this is the largest of the subspecies whereas the bird in question was slightly smaller than the accompanying canus. Based on size and darkness I considered brachyhynchus (Mew Gull) but don't believe that the plumage is correct - the chevron markings on the underparts don't fit with pictures I have found on the web.
As you say maybe the ringers should clamp some metal on its leg and secure a feather for DNA.
Simon
I see your point. Still I felt it was quite hard to get a good feeling on size from the photos. Based on plumage alone I think that kamtschatschensis is most correct. Size alone on the other hand fits in the photos both canus (small one) and brachyhynchus. But this is not based on numbers in hand. Think we have to arrange the ringers, and get blood and measurements.
Slett