Page:The Common Birds of Bombay.djvu/210

194 though they change as they grow older, it is about three years before they acquire the pure grey and white plumage; so there may be a good deal of variety in the colour of a flock. The Herring Gull breeds in Siberia.

Occasionally you will see a gigantic Gull sitting solitary on a buoy. If the hot season is approaching, its whole head and upper neck will be black, but in the cold season it will be pure white all over, save for the pale grey mantle and a little black on the tips of the wings. If it is a youth, it will be more or less brown or mottled. This is the Great Black-headed Gull (Larus ichthyœtus), which breeds in Siberia but roams all over India in the cold season. One other species may be mentioned, which attracts attention at once by its unusual colour. The body and tail are white, but the mantle is dark brown, and the head, neck and breast are more or less brown according to season. This is the Sooty Gull (Larus hempnchi), which meets us in crowds at Aden on the voyage home, and is common, I believe, along the coast as far east as Sind, but only occasionally appears in Bombay harbour.

Among the Terns one may be distinguished by its size. This is the Large Sea Tern, as Jerdon calls it. In the "Avifauna of British India" it is the Large Crested Tern (Sterna bergii). It is pure white, with a grey mantle and a silky black crest. The bill is yellow and the feet black. This large Tern is very common all along the coast, and has a great fancy for perching on the tops of fishing stakes. There is a smaller species which is very like it in colour, but much paler. Jerdon calls it the Smaller Sea Tern