![]() ![]() They are less common on tropical islands, although a few species do live on islands such as the Galapagos and New Caledonia. They breed on every continent, including the margins of Antarctica, and are found in the high Arctic as well. The gulls have a worldwide cosmopolitan distribution. Swallow-tailed gulls are endemic to the Galapagos Islands. The plumage of the head varies by breeding season in nonbreeding dark-hooded gulls, the hood is lost, sometimes leaving a single spot behind the eye, and in white-headed gulls, nonbreeding heads may have streaking. The head of a gull may be covered by a dark hood or be entirely white. The wingtips of most species are black, which improves their resistance to wear and tear, usually with a diagnostic pattern of white markings. A few species vary in this, the ivory gull is entirely white, and some like the lava gull and Heermann's gull have partly or entirely grey bodies. The general pattern of plumage in adult gulls is a white body with a darker mantle the extent to which the mantle is darker varies from pale grey to black. ![]() In the air, they are able to hover and they are also able to take off quickly with little space. The walking gait of gulls includes a slight side to side motion, something that can be exaggerated in breeding displays. They are more adept walking on land than most other seabirds, and the smaller gulls tend to be more manoeuvrable while walking. ![]() Indeed, they are the least specialised of all the seabirds, and their morphology allows for equal adeptness in swimming, flying, and walking. The bill colour is often yellow with a red spot for the larger white-headed species and red, dark red or black in the smaller species. The bill is generally heavy and slightly hooked, with the larger species having stouter bills than the smaller species. Gulls have moderately long legs, especially when compared to the similar terns, with fully webbed feet. The tails of all but three species are rounded the exceptions being Sabine's gull and swallow-tailed gulls, which have forked tails, and Ross's gull, which has a wedge-shaped tail. They are generally uniform in shape, with heavy bodies, long wings, and moderately long necks. Gulls range in size from the little gull, at 120 grams ( 4 + 1⁄ 4 ounces) and 29 centimetres ( 11 + 1⁄ 2 inches), to the great black-backed gull, at 1.75 kg (3 lb 14 oz) and 76 cm (30 in). The Pacific gull is a large white-headed gull with a particularly heavy bill. Gulls have been observed preying on live whales, landing on the whale as it surfaces to peck out pieces of flesh. Others rely on kleptoparasitism to get their food. Many species of gulls have learned to coexist successfully with humans and have thrived in human habitats. Certain species have exhibited tool-use behavior, such as the herring gull, using pieces of bread as bait with which to catch goldfish, for example. For example, many gull colonies display mobbing behavior, attacking and harassing predators and other intruders. Gulls are resourceful, inquisitive, and intelligent, the larger species in particular, demonstrating complex methods of communication and a highly developed social structure. The young are precocial, born with dark mottled down and mobile upon hatching. They lay two or three speckled eggs in nests composed of vegetation. Gulls nest in large, densely packed, noisy colonies. Large white-headed gulls are typically long-lived birds, with a maximum age of 49 years recorded for the herring gull. The large species take up to four years to attain full adult plumage, but two years is typical for small gulls. Gulls are typically coastal or inland species, rarely venturing far out to sea, except for the kittiwakes. Gulls have unhinging jaws which allow them to consume large prey. Live food often includes crustaceans, molluscs, fish and small birds. Most gulls are ground-nesting carnivores which take live food or scavenge opportunistically, particularly the Larus species. They typically have harsh wailing or squawking calls stout, longish bills and webbed feet. Gulls are typically medium to large in size, usually grey or white, often with black markings on the head or wings. An older name for gulls is mews, which is cognate with German Möwe, Danish måge, Swedish mås, Dutch meeuw, Norwegian måke/ måse and French mouette, and can still be found in certain regional dialects. Until the 21st century, most gulls were placed in the genus Larus, but that arrangement is now considered polyphyletic, leading to the resurrection of several genera. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. Flying subadult silver gulls at Kiama beach, Australia, during Christmas 2013 ![]()
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