Azores Gull?

Yellow-legged gulls on Madeira are generally considered to be of the subspecies atlantis also known as Azores gull. However the Madeiran population are a little paler than the birds on the Azores and fall part way between them and classic yellow-legged gull in terms of mantle shade, leaving their true taxonomical status a little vague (at the time of writing). 

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