Great Black-backed Gull (Larus marinus)

(last update: July 12, 2015)

Great Black-backed Gull (Larus marinus) 2cy: May 17 2002, Le Portel - Boulogne sur Mer, France (50.42 N - 01.34 E).

Tertials: #1 - #3 replaced recently, now 2nd gen. Tertials #4 and down into the secondary feathers still juvenile. Base of central secondaries exposed by the dropped greater coverts, these central secondaries obviously still juvenile.
Greater coverts: #1 - #3 replaced early in the complete moult, especially GC2-GC3 already show a whitish, bleached base, missing the brown-grey base tone overall. #4 - #5 just very recently replaced, still buffish brown based. Group of #6 - #10 still juvenile; these feathers are always dropped last in the wing-covert panel, and normally this is the last moult gap in wing-coverts to be detected late July / early August. Greater coverts #11 - #12 missing. GC #13 very fresh. GC #14 and outwards missing.
Median coverts: #1 - #2 replaced early in the complete moult, already show a whitish, bleached base, missing the brown-grey base tone overall. #3 and outwards recently replaced, still buffish brown based.
Lower lesser coverts: mix of recently replaced feathers, still buffish brown based, together with older feathers (like LLC #1), but also probably single juvenile feathers (like LLC #3).
Lesser coverts: same kind of mix as in lower lesser coverts.

below: same image, without text.