Larus fuscus fuscus 2cy, August 03 2002, Stockholm, Sweden.
A second calendar year fuscus with new central median and lower lesser coverts. The outer primaries were all included in the post-juvenile primary moult, so this bird returned in Stockholm with 10 second generation primaries (with rounded tips).
Tertials #1-6 have all been replaced for second generation feathers.
Greater covert #1 is missing, #2-7 were included in the moult last winter and #8-14 (last visible) are fresher, moulted more recently. In the median coverts, #1-4 were included in the winter-moult, #5-8 are much fresher and darker grey, lacking the brown tone of the other coverts, #9 is old and was replaced earlier, #10 is fresher again, lacking abrasion, #11 was moulted on the wintering grounds, #12 (last visible) is fresher. In the lower lesser coverts, #1-2 are old (second generation feathers replaced on the wintering grounds), #3-5 are fresher, #6 is probably missing, #7 is old, #8 is fresher, #9 is old, #10-12 (last visible) are fresher. In the lesser coverts, about 50% (25 feathers) is still old and abraded, replaced on the wintering grounds, while 10% is missing and the others are fresher, darker grey.
The exact age of the scapulars is very hard to ascertain, but three lower upper scapulars are missing. The lower scapulars are fresher, as is the case with several upper scapulars. They are probably third generation feathers, still resembling second generation scapulars in their patterning (an accentuated dark broad central wedge and paler grey towards the fringes).
The recently replaced central median and lower lesser coverts might be third generation as well. The central median and central lower lesser coverts are 'favorite' places to replace feathers in an early stage (post-juvenile moult in September-October) in West-European graellsii and michahellis, and are probably feathers most urgently needed to replace again in the complete moult.
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