The slender-billed gull (Chroicocephalus genei ) is a mid-sized gull which breeds very locally around the Mediterranean and the north of the western Indian Ocean (e.g. Pakistan) on islands and coastal lagoons. Most of the population is somewhat migratory, wintering further south to north Africa and India, and a few birds have wandered to western Europe. A vagrant individual was reportedly seen on Antigua, April 24, 1976 (AOU, 2000).
The genus name Chroicocephalus is from Ancient Greek khroizo, "to colour", and kephale, "head". The specific genei commemorates Italian naturalist Giuseppe Gené.
This species is 37 to 40 cm (14.6 to 15.7 in) long with a 90 to 102 cm (35.4 to 40.2 in) wingspan. It is therefore slightly larger than the black-headed gull, which it resembles, although it does not have a black hood in summer. It has a pale grey body, white head and breast and black tips to the primary wing feathers. The head and dark red bill have an elongated tapering appearance, and this bird also appears long-necked. The legs are dark red, and the iris is yellow. In summer, the breast has a faint pink colouration. This bird takes two years to reach maturity, as is usual in gulls. First year immature birds have a black terminal tail band, and dark areas on the wings.
