Lesser Black-backed Gull (graellsii & intermedius)

(last update: 22-2-2011)

LBBG 3cySeptember 24 2001, IJmuiden, the Netherlands.

A 3cy LBBG, probably with a Dutch ring, maybe even from IJmuiden colony. Clues for 3cy are:

1. black markings in the rectrices,
2. tertials without a complete white tip, but white tip confined to the inner web (it remains unclear whether this only applies to immaturity),
3. old visible secondaries with brown spaghetti pattern,
4. some of the lesser coverts, especially in the carpal edge, typical brown,
5. no white mirror on P10 and white tips on the bleached brown outer primaries hardly developed.

An example of an individual which may arrest the moult, although it is known that the moult gap in the primaries can be very small in LBBG (certainly when compared to e.g. Herring Gull and Yellow-legged Gull). P6 is full-grown, P7 is over half of it's length and still P8 has not been shed; P8 to P10 are old. It's interesting to find out to what extend such graellsii/intermedius LBBGs really suspend or arrest the moult at this stage. Notwithstanding the small moult gap, they may even complete the primary moult in an ordinary way. Maybe research in Southern Europe can answer this question.