Great Black-backed Gull (Larus marinus)

(last update: July 12, 2015)

Great Black-backed Gull (Larus marinus) sub-adult, September 17 2001, Vuurtorenvlakte, Maasvlakte, the Netherlands (51.59 N - 04.01 E).

Primary p5 fully grown and p9-p10 still present. Both old primaries show a mirror, the mirror on p10 merges with the white tip. Probably this is an older sub-adult with many adult-like features and a late primary moult. However, note the extensive black markings on the bill.