Atlantic Yellow-legged Gull (atlantis)

(last update: October 12, 2011)

Coordinators:
Rui Caratão (Portugal)
Mars Muusse (Netherlands)

Atlantic YLG (atlantis) adult, May 08 2011, Canico - Madeira. Picture: Graham Ekins.

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No black on P4, full sub-terminal band on P5. Mirror on P10, but none on P9. Red spreads only marginally on upper mandible.

Graham's photo comment:

These very dark backed adult gulls approach graelsii Lesser Black-backed Gull in mantle colour. The Azorean birds being the darkest. In this race on the tip of primary 5 there is a large back band on an otherwise paler feather. This is much reduced in Herring Gull.
The immature plumages can be confused with Lesser Black-backed Gull. However, their bills have a heavier gonys angle and they have a pale area on the inner primaries, these are dark in Lesser’s. From 2nd year onwards they also have more red on the bill which like this bird extends on to the lower edge of the upper mandible.
The Atlantis form of Yellow-legged Gull breeds on Madeira, Canaries and Azores. It is an uncommon, mainly winter visitor to Cape Verde. We had a first summer bird fly in off the sea and into Praia Harbour, Santiago, Cape Verde on the 3rd May 2011, an unusual record.