Great Black-backed Gull (Larus marinus)

(last update: July 12, 2015)

Jean-Michel Sauvage (France)
Morten Helberg (Norway)
Nils Helge Lorentzen (Norway)
Mars Muusse (Netherlands)

Great Black-backed Gull (Larus marinus) 2cy: June 14 2002, Le Portel - Boulogne sur Mer, France (50.42 N - 01.34 E).

Primary moult stage: p6 as long as p5 and p9-10 still juvenile. In NW France 2cy Great Black-backed Gull show very advanced primary moult with higher moult scores than surrounding michahellis, argenteus and graellsii
An individual with active moult in the rectrices, as can be seen in the missing central tail-feather. The wing-coverts moult to second generation is almost completed with all greater coverts fresh. The two lower tertials are still missing. Median covert #12 is slightly shorter than other median coverts. The upper rows of the lesser coverts are growing simultaneously. The majority of the scapulars (70%) has been moulted to third generation.

A very advanced bird regarding plumage moult. Soft parts still very immature, juvenile-like.