Herring Gull- Zilvermeeuw (argentatus & argenteus)
Herring Gull plumages:
hg sub-ad January
Herring Gull 3cy (argentatus), January 04 2002, Le Portel / Boulogne-sur-Mer, France (50.42N,1.34E).
A 3cy argentatus,
which shows a delicate fine black pattern on a very pale base. The new
third generation upper scapulars
are not plain adult-like grey as in most argenteus, but the
scapular region are moulted to third generation feathers which strongly
resemble the second generation feathers. Consequently, 3cy argentatus
may look very delayed in their moult, compared to argenteus in
mixed groups and they can sometimes be mistaken for 2cy birds.
Compared to argenteus, argentatus may show finer, more
delicately black-patterned feathers, not as bold and smudgy as many argenteus
show (especially in the second generation central greater coverts).
This individual has replaced many wing-coverts in the partial autumn moult as 2cy bird: the upper three tertials, the inner greater coverts, most of the visible median coverts and two inner lower lesser coverts have been replaced. The new feathers show a buffish hue on the pale parts and have fresh fringes and tips.