Herring Gull- Zilvermeeuw (argentatus & argenteus)

(last update: 9-2-2007)

(2 images) Herring Gull  DA 228127 3cy (argenteus), March 16 2003, Boulogne-sur-Mer, France (50.42N,1.34E).

A typical argenteus, ringed in France, metal DA 228127. As can be seen in many of the argenteus Herring Gulls with a French ring (most probably from the population breeding in the Calais region) the moult stage and bare parts coloration is advanced compared to Belgium and Dutch argenteus. See e.g. these birds:

• DA 212950, 2cy argenteus in April, June & July
• DA 216321, 2cy argenteus in May, June & July
• DA 216323, 2cy in April, May & June
• adult March

The new scapulars are plain adult-like pale grey contrasting with the barred lesser coverts, creating a grey saddle in this individual. The bill is typical for 3cy birds, but advanced in coloration compared to other argenteus in March: already yellow at the base, a red gonydeal spot and a broad bill-band. Note the rather pale yellow iris and the red orbital ring. The black-brown second generation primaries lacking the mirror on P10, although there is a whitish patch at the place where the mirror will appear in later years. Compared to Scandinavian argentatus, the general impression resembles argentatus in 4cy, which also show an almost complete grey scapular region and single grey feathers in the tertials, inner greater coverts and a few lesser coverts.
The moult-stage of 3cy argenteus is sometimes difficult to interpret by March. The scapulars are more or less uniform grey. Many grey scapulars appear abraded at the fringes already, especially in the upper scapulars.
This French individual has moulted the upper tertials (now barred) and some wing-coverts in the partial autumn moult as 2cy bird: tertials #1-3 have been replaced, greater coverts #1-2, all but two visible inner and central median coverts have been replaced. In the lower lesser coverts, the central and outer feathers have been replaced and five lesser coverts were included in the partial autumn moult. The new feathers have fresh fringes and tips and are adult-like in their patterns, most are completely grey.