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, September 21 2002, Dannes / Boulogne-sur-Mer, NW France. 

This is a 2CY michahellis which started the partial moult in the wing-coverts. Tertials #1-3 are new, greater coverts #1-2 are new, median coverts #1-2 and #7 and further outwards are new. In the lower lesser coverts #1-2, #4-5 are new and #11-13 are missing. The lower lesser coverts contain two new and two missing feathers. The new scapulars have a grey base and brown sub-terminal bar. The exact age of these new scapulars is difficult to ascertain, there are a few lower scapulars which probably belong to third generation, but a few upper scapulars are probably fourth generation, although they still appear third generation-like in pattern. This of course is quite different from the development of scapular pattern in e.g. argenteus. See Gull Topography for explanation of feather tracts.