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 with almost all wing-coverts moulted to second generation. Last juvenile wing-coverts can be found in the upper row of the lesser coverts (the carpal edge), just beneath the scapulars. Almost half of the lesser coverts are missing and many have been replaced already for second generation coverts. The gap in the greater covert row has been closed. The outer greater coverts moult inwards, the inner coverts moult outwards and the two tracts meet at about covert #8. The tertials are second generation as well.

This bird is moulting the rectrices, with R3-R4 still growing. Primary moult stage: P9-P10 still juvenile, P5 fully grown. Recently moulted lower upper scapulars have buffish centres and show the same (second generation like) pattern as the white based lower scapulars. The soft parts are very immature with the bill mostly black.