nominate Lesser Black-backed Gull (L. f. fuscus)

(last update: 16-12-2010)

Larus fuscus fuscus 2cy, December 10 2010, Ashdod. Picture Amir Ben Dov.

2cy nominate fuscus by December, showing so-called Periodische Staffelmauser. This means that the moult process in the primaries occur in several waves, which not necessarily start at P1 each time, and thus may result in two simultaneous moult waves in the wing. In fact, it is quite normal for nominate fuscus to moult primaries in such a way, and therefore only few immature fuscus birds show the typical sequence as is found in the complete moult in other taxa.
Here, P1-P2 are very new, P3 has been dropped, P4-P9 are fully grown 2nd generation primaries and P10 is currently growing as well, with a small but obvious mirror. Several outer median are almost adult-like blackish, and the central and inner medians are missing. The tail is in active moult as well, and part of the inner secondaries show large white tips, typically associated with 3rd generation feathers. The location of this group of feathers however is interesting; as this is normally the last cluster of secondaries moulted in an "ordinary moult sequence" in large white-headed gulls (S16-S18).