Gull
Common name for approximately 47 species of long-winged, web-footed seabirds, the most familiar birds of the seashore. The commonly used name sea gull is a misnomer. Many species nest or feed inland, and most of the rest are strictly coastal; only the kittiwakes are truly oceanic during the nonbreeding season. Gulls are distributed worldwide, excluding only tropical deserts and jungles, the central Pacific islands, and most of Antarctica. Some gulls are migratory.
Characteristics
Gull sizes, from bill to tail, range from 27 to 80 cm (11 to 31 in). The bill is hooked. Except for the totally white ivory gull, the birds vary from pale gray to black above, and from white to gray below. The heads of many have black, gray, or dark brown hoods during breeding season. Many of the gray-winged species have black or darker gray wing tips, often with white spots. The sexes are alike in color. The young have mottled brown or gray plumage, taking as long as four years (in the larger species) to attain the definitive adult coloration through a progressive series of annual molts.
Gulls are equipped for versatility rather than specialization. For example, their wings are good for soaring as well as for strong and agile powered flight, but they cannot use air currents as efficiently as albatrosses or fly as fast as falcons. The foraging of gulls includes fishing, scavenging, egg predation, insect catching, following plows for earthworms and ships for garbage, dropping shellfish from a height to break them open, and foot paddling to stir up organisms in shallow water.