Gulls in NW Europe
(last update: September 25, 2011
Herring Gull sub-adult (argenteus) August 22 2012, Katwijk, the Netherlands.
Immature appearance, and may be taken for an advanced 3cy, but most probably in 4cy, lacking a mirror on P10; but note the rather adult-like centres of the old secondaries and mature bare part coloration. P6/P8.
