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 1CY, October 03 2002, Le Portel, NW France.

This 1CY michahellis has started the partial moult in autumn (post-juvenile moult): the upper two tertials have been shed; the inner greater coverts #1-2 are replaced and #3 is growing; median coverts #2-4 are new, #5 is growing, #6 is missing and #7 is new, #8 is missing, #9-10 & #13 are new.
In the lower lesser coverts #5-6 are replaced, #7-8 are missing, #10 is growing, #11-12 new. About five lesser coverts are replaced for second generation feathers. All feathers not mentioned are still juvenile.
A small number of michahellis (about 5%) moult some of the tail-feathers in autumn of it's first calendar year. This individual has replaced two tail-feathers and two tail-feathers are missing.