Herring Gull (argentatus & argenteus)

(last update: February 11, 2013)

Herring Gull sub-adult, July 18 2013, Noordwijk, the Netherlands.

4CY, no ring, no provenance on origin and age.
Aged by vestiges of immaturity, most noticable dark markings in centres of the greater porimary coverts, in combination with adult-like pattern on primaries and secondaries. Probably moult arrested at late stage, leaving inner secondaries and one tail-feather (R5) old, which indicate 4CY bird.
Active moult in primaries (complete moult in summer months): P4/P7, and P6 almost at full length.