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 23 2003, IJmuiden, the Netherlands (52.27 N - 04.33 E).

An individual in active wing-covert moult to second generation. The median coverts have been replaced. The inner lower lesser coverts and inner greater coverts have been replaced and current moult arrived at the outer lower lesser coverts (missing and several fresh tips visible) and the outer greater coverts coverts (missing). The lesser coverts are still juvenile, but a few outer lesser coverts in the lowest row are missing. The upper tertials are second generation as well.

This bird has the rectrices still juvenile, but the inner pair will be dropped soon. Primary moult stage: P7-P10 still juvenile, P4 fully grown. As can be seen in the picture, all secondaries are still juvenile. Only a few scapulars have been renewed recently: several lower scapulars show buffish centres and a few lower upper scapulars have been moulted to third generation feathers, still with a pattern like second generation scapulars. The soft parts are very immature but the bill-base starts to turn pinkish.