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First-winter Yellow-legged Gull Larus michahellis
First-winter Yellow-legged Gull, 18th April, 2000

Note how similar Yellow-legged may appear to Herring at this time of year, but characteristic details exist:

• The black "mask" around the eye;

• The relatively un-notched greater coverts (not forming the marked bar of Caspian)

• The neat narrow, black tail band, contrasting with unmarked white tail base - the marks visible are on the uppertail coverts.

Further evidence is that of the very early moult of the inner greater coverts and some median and lesser and three tertials.
First-winter Yellow-legged Gull, 20th December, 1999
1st-winter Yellow-legged Gull, 5th January, 2000
1st-winter Yellow-legged Gull, 22nd December, 1999