Larus melanocephalus – Gwylan Môr y Canoldir – Winter visitor
The Mediterranean Gull was first recorded at Skokholm, in 1968, when a second-winter bird was seen on five occasions between 3 and 17 November. The species was subsequently recorded in six of the next twelve years, becoming annual from 1980. The early records were all of single birds which did not stay long, but since 1980 one or two have wintered at Fishguard Harbour and there are records from various parts of the Cleddau Estuary, including Llanstadwell, the Gann and Angle Bay, in most winters.
Comparison of the combination of head and bill markings of individuals revealed that four Mediterranean Gulls wintered at Fishguard Harbour in late 1986, and that they forayed daily west to Strumble Head or east to the Nevern Estuary. Five were there in the winter of 1992/93. It is suspected that these birds, as well as those that are seen on the Cleddau Estuary, also feed inland during the day but so far they have only been seen at Roch Gate, Hill Leys and Treigo. The Mediterranean Gull has only twice been recorded from the south coast of Pembrokeshire, at Lydstep and at Bosherston Pools.