Elegant Tern
Thalasseus elegans
Long-billed tern of the Pacific coast, from the U.S. to Chile. Pale gray above with shaggy black cap in breeding plumage; nonbreeding birds develop white forehead. Best field mark is the slender orange bill with a slight droop. Strictly coastal; commonly found on beaches and estuaries. Similar to Royal Tern but smaller and slimmer with a thinner bill. Harsh grating calls similar to other terns.
识别特征
The elegant tern (Thalasseus elegans) is a tern in the family Laridae. It breeds on the Pacific coast of southern California in the United States and western Mexico, and migrates south to Peru, Ecuador and Chile for the northern winter; in the late summer and fall, some also disperse north to Oregon and more rarely Washington. This species breeds in very dense colonies on coasts and islands, including Isla Rasa and Montague Island in Mexico, as well as South Bay Salt Works (San Diego) and Bolsa Chica Ecological Reserve in California. Exceptionally, vagrants can occur inland on suitable large freshwater lakes. The elegant tern feeds by plunge-diving for fish, almost invariably from the sea, like most Thalasseus terns. It usually dives directly, and not from the "stepped-hover" favored by the Arctic tern. The offering of fish by the male to the female is part of the courtship display. This Pacific species has wandered to western Europe as a rare vagrant on a number of occasions. The first European record was at Carlingford Lough in County Down, Northern Ireland, in late June 1982. It has nested in Spain, and has interbred with a Sandwich tern in France. There is also one record from Cape Town, South Africa, in January 2006, the first record for Africa.
分类信息
The current genus name is derived from Greek Thalassa , "sea", and elegans is Latin for "elegant, fine". [ 9 ] Though described in 1822, the genus was largely treated as a synonym of Sterna until a 2005 study demonstrated that the systematics of the terns needed review. [ 10 ] The closest relative of the elegant tern is Cabot's tern T. acuflavidus , which breeds on the Atlantic coasts of the Americas; this species pair is then next most closely related to the Old World Sandwich tern . [ 11 ] [ 12 ] [ 13 ]
- 学名
- Thalasseus elegans
- 命名信息
- (Gambel, 1849)
- 目
- Charadriiformes
- 科
- Laridae
- 属
- Thalasseus
分布与栖息地
Breeding range: NA, MA : coastal e Pacific of sw California and Baja California and Gulf of California (nw Mexico). Non-breeding range: to coastal e Pacific from n California to c Chile.
- 繁殖区
- NA, MA : coastal e Pacific of sw California and Baja California and Gulf of California (nw Mexico)
- 非繁殖区
- to coastal e Pacific from n California to c Chile
- 迁徙
- Complete migrants
行为
Migration pattern: Complete migrants.
保护状况
Population trend: stable.
- 种群趋势
- stable
照片
分布
鸟叫声
其他鸟类
Banggai Crow
Corvus unicolor
An entirely black, short-tailed, pale-eyed crow confined to the island of Peleng in the Banggai Islands. Occurs in groups within canopy of montane forest. Tail just barely extends beyond wingtips when perched. Shorter-tailed and shorter-billed than Slender-billed Crow, and shows a pale eye, unlike that species. Voice also differs. Song is a “whee-kew-kew-kew,” with a rasping note starting the series and higher-pitched, ascending whistles following.
Nubian Woodpecker
Campethera nubica
Mid-sized green-backed woodpecker with intricate patterning. The crown is red in males, red and white-speckled black in females. Note the heavily streaked ear, bold spotting below, and plain white throat. Generally common and conspicuous in most types of savanna habitat. Usually in pairs, which give a loud duet of “keek” notes. Very similar to Bennett’s Woodpecker, but separated by the black-streaked ear. Also similar to Golden-tailed and Mombasa Woodpeckers, but easily separated by the spotted rather than striped underparts.
Malagasy Palm Swift
Cypsiurus gracilis
A very slender gray-brown swift with a long, deeply forked tail that is often held closed, making it look needle-like and pointed. The erratic flight pattern, with frequent direction changes and rapid wingbeats on long, scythe-shaped wings, is distinctive. Less gregarious than other swifts; usually found in pairs or small flocks, and association with other swallows and swifts is usually only fleeting. Forages over a wide variety of habitats with palms, including savanna, coastal scrub, towns, villages, cultivated areas, forest edge, and clearings, from sea level up to 1100 meters of elevation, preferring lowlands. Nests and roosts in palms, especially Hyphaene, Bismarckia, and coconut palms. Gives a high-pitched, metallic “tre-tit-tit-tit-tit-tit-tit-tit” call, solitarily or in unison with others. Separated from other swifts by its longer and thinner tail. Further separated from the larger Madagascar Swift by its much weaker and more fluttering flight.
开始您的观鸟之旅
在户外识别鸟类，并在下一次观察时随手查阅鸟类图鉴。