Gulls
Gulls In North America
The name "sea-gull" does not really apply to any particular species of bird. However, this name would be most appropriately used to describe the herring gull (Larus argentatus), which is the world's most widely distributed species of gull. The herring gull breeds extensively on the coasts of large lakes, rivers, and the oceans of North America and Eurasia. The herring gull spends its non-breeding season in the southern parts of its breeding range, and as far into the tropics as the equatorial coasts of Africa, the Americas, and Southeast Asia. The taxonomy of herring gulls has engendered some controversy among ornithologists due to confusion about the identity of subspecies and whether some of these should be considered as distinct species. Herring gulls breed freely with other seemingly distinct gulls, including the Iceland gull (L. glaucoides), Thayer's gull (L. thayeri), and even the considerably larger, glaucous gull (Larus hyperboreus).
The world's largest gull is the greater black-backed gull (L. marinus). This large, black-mantled species breeds on the north Atlantic coasts of both North America and Europe.
The glaucous-winged gull (L. glaucescens) is an abundant species on the west coast of North and Central America. The western gull (L. occidentalis) is a black-backed species of the west coast of North America and is rather similar to the lesser black-backed gull (L. fuscus) of Europe, which sometimes strays to North America during the non-breeding season.
The ring-billed gull (L. delawarensis) is a common and widespread breeding gull, particularly on prairie lakes and on the Great Lakes, migrating to winter on the Atlantic and Pacific coasts.
The California gull (L. californicus) breeds in large colonies on prairie lakes and winters along the Pacific coast. This is the species of gull that "miraculously" descended on the grasshopper-infested fields of the first Mormons in Utah, helping to save their new colony. When grasshoppers are abundant, these gulls will gorge themselves so thoroughly with these insects that they are temporarily unable to fly.
The laughing gull (L. atricilla) breeds on the coast of the Gulf of Mexico and the Atlantic states. Like other black-headed gulls, this species has a white head, with some black spots, during the non-breeding season. Franklin's gull (L. pipixcan) is another black-headed species, breeding on small inland lakes, potholes, and marshes of the prairies, and migrating to the west coast of South America to spend the winter. Bonaparte's gull (L. philadelphia) breeds beside lakes and in other wetlands in the subarctic taiga and muskeg. This species commonly builds its nests in short spruce trees.
The black-headed gull (Larus ridibundus) is a small, widespread European species, which has recently begun to breed in small numbers in eastern Canada, particularly in Newfoundland.
Almost all species of gulls are in the genus Larus. One exception in North America is the kittiwake (Rissa tridactyla), a subarctic, highly colonial, cliff-nesting marine species that lacks the hind toe found in other species of gulls. The kittiwake breeds in large colonies in various places in the Canadian Arctic as well as in northern Eurasia. This species spends its non-breeding season feeding pelagically at sea, as far south as the tropics.
Another non-Larus species is Sabine's gull (Xema sabini), a fork-tailed gull that breeds in the arctic tundra of northern Canada, Greenland, Spitzbergen, and Siberia, and migrates down both the Atlantic and Pacific coasts to winter at sea off Peru and eastern South Africa. The ivory gull (Pagophila eburnea) is a rare, all-white species that only breeds in a few small colonies in the High Arctic of Canada and Siberia.
Ross's gull (Rhodostethia rosea) is another rare gull of the Arctic, breeding in a few places in eastern Siberia and, very rarely, at Hudson Bay in Canada. Ross's gull is a particularly beautiful small-sized gull, with bright-red legs and subtly pink breast and face plumage. On rare occasions, individuals of Ross's gull will wander to more southerly regions of North America, to the great excitement of many bird watchers.
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