Herring
Gull 5.335.119
2cy (argenteus), April 12 2001, IJmuiden,
the Netherlands (52.27N 04.33E).
A Dutch ringed argenteus, Vogeltrekstation Arnhem: 5.335.119, ringed as pullus at Bloemendaal, on May 29 2000. Now in 2cy, this individual shows the common moult stage in 2cy argenteus by April: the juvenile wing-coverts and tertials are abraded, the primaries are bleached brown and the bill-base starts to turn paler. The upper lower scapulars have been replaced for second generation feathers, with the last moulted scapulars showing buffish tones on the centres.
Argenteus will show a second partial moult of head and body-feathers in spring. This partial moult starts in January and ends by May, bringing birds in so-called "first summer" plumage. The head and under-parts will turn white by June.
By April, some argenteus will show three generation of scapulars: still a few juvenile scapulars in the rear lowest row (first generation), a few very fresh lower upper scapulars with a clear buffish tone and a neat white fringe, still with a similar pattern as the second generation feathers (third generation) and most scapulars are slightly worn upper scapulars and upper lower scapulars (second generation). The juvenile tertials, lesser, lower lesser and median coverts have a notched pattern, worn by April. The juvenile greater coverts show a 'piano-key' pattern; in argenteus on the outer greater coverts as well. This pattern has gone lost as the white parts of the feathers are worn away. The juvenile tertials are very abraded as well.
The secondaries, primaries and primary coverts are bleached, but the juvenile inner primaries still show an obvious pale window, prominent from below and above. The under-wing is rather uniform grey-brown patterned. The tail has a broad sub-terminal band and isolated dark bars on the basal half.
|