Herring Gull - Zilvermeeuw (argentatus & argenteus): sub-adult February
(last update: 07 april 2004)
4cy (argenteus), February 07 2003,
Boulogne/Mer, France (50.43N-01.37E).
A 4cy argenteus ringed as pullus on July 08 2000 at Zeebrugge, Belgium (51.20N 03.11E): Bruxelles H-108933. This agenteus shows all the familiar characteristics of a 4cy in February:
From January to April, 4cy argenteus moult to so-called "third summer" plumage. The head and under-parts will appear all-white by early May. The tail-feathers, wing-coverts and primaries are not replaced in this moult, therefore most birds strongly resemble "third winter" birds, although the white primary tips wear away and dark patches start to bleach. The iris is often yellowish, the orbital ring yellowish-orange in argenteus and the bill predominantly yellow with a red gonydeal spot and limited black markings along the culmen by April.