The Gull-Billed Tern — Sterna Anglica, Montagu
With this species we come to the true Terns or Sea-Swallows, the preceding species being known as Marsh Terns. The Gull-billed Tern is only a very scarce straggler to our shores, being a southern European species though occurring yearly as far north as Denmark.
In habits there is nothing to distinguish it from our commoner species.
In summer the adult has the whole of the upper parts, including the tail, pearl grey; head and nape dense velvety black; primaries blackish. Under parts pure white; bill and legs black. In winter the head is white streaked with black. Length 15·5 in.; wing 13 in.