Herring Gull (argentatus & argenteus)

(last update: February 11, 2013)

Herring Gull 4CY, March 13 2013, Noordwijk, the Netherlands.

Third generation flight feathers: inner primaries appear adult-like, including P5; outer primaries immature looking, lacking mirror on P10. When resting, bird may be mis-aged as 3CY.