Yellow-legged Gull - Larus michahellis

(last update: October 08 2013)

Delfín González
Gabriel Martín
Antonio Gutierrez
Amir Ben Dov
Mars Muusse

Yellow-legged Gull michahellis 2CY, May 04 2001, Etaples, NW France (50.42N,1.34E).

2CY michahellis with a few third generation grey scapulars. Michahellis normally moult at least some median coverts and in many cases also the inner greater coverts and randomly some inner lesser coverts to second generation feathers in the post-juvenile moult (first pre-basic moult). Therefore, by May, 2CY michahellis show many old and abraded second generation wing-coverts. This is an easy clue to distinguish it from West-European Herring Gulls, argenteus, which may moult one or two median coverts to second generation feathers in autumn, but in 97% of the Herrings, all wing-coverts are juvenile, throughout the winter. By May, birds with old juvenile wing-coverts, combined with onlyfresh second generation wing-coverts, therefore are most probably Herrings. Nevertheless, even some michahellis may show complete juvenile wing-coverts by early May, as some pictures on this site show.