Great Black-backed Gull (Larus marinus)

(last update: July 12, 2015)

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

Great Black-backed Gull (Larus marinus) adult, September 20 2015, IJmuiden, the Netherlands.

P5/P8. Large mirror on both P9 and P10. Rectrices and secs moult. Some old coverts have a brown hue.