Probably the most common gull in Portugal, especially in the winter, but Black-headed Gulls tend to breed further north. The head is not actually black but dark chocolate and during the winter months it shows an almost white head with two black lateral lines, one behind the eye culminating in a prominent black "ear", and one above the eye and reaching over the head. In winter birds the beak is dark orange to red with a black tip, while in summer plumage the beak is a consistent dark red. The back is light grey throughout the year and the belly remains white also. Juveniles show a scaly orange tinge to the back and wing feathers and the head is also tinged orange.
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