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).

An example of a 2CY ("first summer" / first alternate) michahellis with about 8 third generation grey scapulars (50% of the visible area on side view). By May, only very limited numbers of michahellis lack grey ot grey-based, third generation scapulars. Nevertheless, as an identification feature it's not very strong since some argenteus, graellsii and commonly intermedius share this moult strategy of the scapulars, but it seems to be more common in michahellis and the advanced stage in some michahellis (over 90% of the scapulars grey) is very unlikely to be found in LBBG's. Argenteus may show new grey scapulars, but only a few at most.
Here, note the common pattern on the second generation tertials (all 6 tertials have been moulted) in michahellis: a broad white bar at the tip and a small sub-terminal band. Almost all visible coverts are second generation: just a few (1/3) outer greater coverts, outer 20% of the lessers and outer 25% of the medians on the left wing prove to be juvenile. Of the many michahellis we saw in Etaples and Le Portel, 2CY birds in May did not really appear white-headed. Here, winter streaking is concentrated in the lower neck, a feature shared with 2CY cachinnans.
The complete tail appears to be second generation as well.
Note the bill: not necessarily all black in 2CY michahellis.
Probably, this is a female.