A large, heavily built Tern that is officially only a winter visitor and keeps to the coast, but I have seen them both inland over the lake in front of the Quinta and also in September, which is not particularly winter. Sandwich Terns have a long black bill with a distinct yellow tip, and a small crest at the back of the head and they're the only Tern, (apart from the Caspian), that is relatively common in the area to have a totally white neck as all the others have a black nape.
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