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) 4cy: January 13 2012, IJmuiden, the Netherlands.

Scapulars, median coverts and tertials show adult-like greyish black colour. Primaries with obvious white tips and distinct mirror on P10 and P9. Still many vestiges of immaturity in several feather tracts indicate 4cy. Note adult like secondaries.