Herring Gull- Zilvermeeuw (argentatus & argenteus)

(last update: 24-12-2006)


Herring Gull plumages:

hg 1cy July
hg 1cy August
hg 1cy September
hg 1cy October
hg 1cy November
hg 1cy December

hg 2cy January
hg 2cy February
hg 2cy March
hg 2cy April
hg 2cy May
hg 2cy June
hg 2cy July
hg 2cy August
hg 2cy September
hg 2cy October
hg 2cy November
hg 2cy December

hg 3cy January
hg 3cy February
hg 3cy March
hg 3cy April
hg 3cy May
hg 3cy June
hg 3cy July
hg 3cy August
hg 3cy September
hg 3cy October
hg 3cy November
hg 3cy December

hg sub-ad January
hg sub-ad February
hg sub-ad March
hg sub-ad April
hg sub-ad May
hg sub-ad June
hg sub-ad July
hg sub-ad August
hg sub-ad September
hg sub-ad October
hg sub-ad November
hg sub-ad December

hg ad January
hg ad February
hg ad March
hg ad April
hg ad May
hg ad June
hg ad July
hg ad August
hg ad September
hg ad October
hg ad November
hg ad December

Herring Gull 1036 2cy (argenteus), December 24 2004, Westkapelle, the Netherlands (51.33N 03.25E). Picture by Pim Wolf.

An orange ringed argenteus, probably ringed in the York project, U.K. A few new scapulars appear rather pale plain grey, but most feathers are second generation-like showing bars and anchors. The bill is typical for 2cy birds. The second generation primaries are dark brown and the tips are very limited.
After the complete moult, a partial moult started in September and included several wing coverts (see e.g. the inner greater coverts) and the upper tertials. These feathers appear fresher in the wing.

The complete moult in argenteus is finished by October and overlaps with the partial autumn moult. Between September and November, the average 2cy argenteus start a simultaneous partial autumn moult in the wing-coverts, including the upper tertials, some median and lower lesser coverts and often the inner greater coverts.
The head shows neat fine streaking and the under-parts and rump are pale, mottled with brown. The scapulars and mantle are replaced for third generation feathers, finishing with the replacement of the rear lowest scapulars. The pattern of these third generation scapulars is more or less similar to the anchor pattern of the second generation feathers. Simultaneous with replacement of the lowest scapulars, argenteus moult some of the lower upper scapulars in November. By October, argenteus the new scapulars may appear adult-like pale grey or grey-based. 

By early October, argenteus finish the complete moult, with the central greater coverts and outer lesser coverts moulted last. By December, argenteus has finished the primary moult. The second generation tail-feathers show a clear-cut blackish tail-band with only isolated blackish markings on the white basal half.