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Friday, 6 January 2012

White-winged Swallow

White-winged Swallow

The White-winged Swallow, Tachycineta albiventer, is a resident breeding bird in tropical South America from Colombia, Venezuela and Trinidad south to northern Argentina. Being non-migratory, stray birds are not often encountered; one was seen on July 6, 1996, on the Tuira River downstream of Unión Chocó, Panama, and another one at Schoelcher, Martinique, on August 10, 1993.
The adult White-winged Swallow is 13.2 cm long and weighs 17 g. It has iridescent blue-green upperparts, white underparts and rump, and white edgings to the secondary flight feathers. The sexes are similar, but juvenile plumage is grey brown above apart from the white rump.
The call is a harsh chirrup.
White-winged Swallows are easily distinguished from the related Tree Swallow, which has occurred within its range, by the white in the wings; this is lacking in the otherwise quite similar Tree Swallows. White-winged swallows also have a heavier bill than North American species.
The White-winged Swallow is usually found near water, and feeds primarily on flying insects. It normally occurs in pairs or small flocks.
This swallow builds a cup nest lined with other birds' feathers and some seed down in a tree hole,between boulders or in man-made structures. The clutch is 3-6 white eggs. A nest in Cuyabeno Reserve (Ecuador) was found to contain recently-hatched young on August 30, 2003.

Blue-and-white Swallow

Blue-and-white Swallow

The Blue-and-white Swallow (Notiochelidon cyanoleuca) is a passerine bird that breeds from Nicaragua south throughout South America, except in the deserts and the Amazon Basin. The southern race is migratory, wintering as far north as Trinidad, where it is a regular visitor. The nominate northern race may have bred on that island.
Sometimes placed in the genus Pygochelidon,it was first formally described as Hirundo cyanoleuca by French ornithologist Louis Vieillot in 1817, based on a specimen he believed to be from Paraguay.The scientific names mean the same as the English common name.The adult Blue-and-white Swallow averages 11–12 cm long and weighs about 10g. It has dark blue upperparts and white underparts, and its underwings and the undersurface of its short forked tail are blackish. The juvenile is brown above, buff-tinted below, and has a less forked tail.The call is a buzzing dzzzhreeee.
There are three subspecies. The nominate N. c. cyanoleuca occurs from Nicaragua and Trinidad south to northwestern Argentina, Paraguay and Uruguay. The migratory southern race N. c. patagonica is larger (13.5 cm), has paler underwings, and white basal undertail coverts. N. c. peruviana is restricted to coastal Peru up to 2500 m altitude. It is smaller than patagonica, has less white in the undertail, darker underwings and duskier flanks.


Surucua Trogon

Surucua Trogon

The Surucua Trogon (Trogon surrucura) is a species of bird in the Trogonidae family. It is found in humid forest and nearby habitats in south-eastern Brazil, eastern Paraguay and far north-eastern Argentina. It includes two subspecies; the southern nominate subspecies with a red belly and the northern aurantius with an orange-yellow belly. The latter has sometimes been considered a separate species, the Brazilian Trogon (Trogon aurantius). The name Orange-bellied Trogon has also been suggested, but this leads to confusion with the Central American Trogon aurantiiventris.

Wood Stork

Wood Stork

The Wood Stork (Mycteria americana) is a large American wading bird in the stork family Ciconiidae. It was formerly called the "Wood Ibis", though it is not really an ibis.The adult is a large bird 83–115 cm (33–45 in) tall and 140–180 cm (58–71 in) in wingspan. Males typically weigh 2.5–3.3 kg (5.5-7.3 lbs); females weigh 2.0–2.8 kg (4.4-6.2 lbs),although large birds are up to 4.5 kg (10 lbs).It appears all white on the ground, with blackish-gray legs and pink feet. In flight, the trailing edge of the wings is black. The head is dark brown with a bald, black face, and the thick downcurved bill is dusky yellow. Juvenile birds are a duller version of the adult, generally browner on the neck, and with a paler bill.This is a subtropical and tropical species which breeds in much of South America, Central America and the Caribbean. The Wood Stork is the only stork that presently breeds in North America. In the United States there is a small and endangered breeding population in Florida, Georgia, and South Carolina, along with a recently discovered rookery in southeastern North Carolina. On the other hand, in Santa Catarina state (Brazil), its decline seems to have been reversed: after an absence between the late 1960s and the mid-1990s, the species is now again regularly encountered there, in particular in the Tubarão River region.It is likely that the Paraná River region's wetlands served as a stronghold of the species, from where it is now re-colonizing some of its former haunts.Globally, it is considered a Species of Least Concern by the IUCN due to its large range.
The Wood Stork is a broad-winged soaring bird that flies with its neck outstretched and legs extended. It forages usually where lowering water levels concentrate fish in open wetlands; it also frequents paddy fields. Walking slowly and steadily in shallow water up to its belly, it seeks prey, which, like that of most of its relatives, consists of fish, frogs and large insects. It catches fish by holding its bill open in the water until a fish is detected.


Black-winged Stilt

Black-winged Stilt

The Black-winged Stilt or Common Stilt (Himantopus himantopus) is a widely distributed very long-legged wader in the avocet and stilt family (Recurvirostridae). Opinions differ as to whether the birds treated under the scientific name H. himantopus ought to be treated as a single species and if not, how many species to recognize. Most sources[citation needed] today accept 2–4 species.Adults are 33–36 cm long. They have long pink legs, a long thin black bill and are blackish above and white below, with a white head and neck with a varying amount of black. Males have a black back, often with greenish gloss. Females' backs have a brown hue, contrasting with the black remiges. In the populations that have the top of the head normally white at least in winter, females tend to have less black on head and neck all year round, while males often have much black, particularly in summer. This difference is not clear-cut, however, and males usually get all-white heads in winter.
Immature birds are grey instead of black and have a markedly sandy hue on the wings, with light feather fringes appearing as a whitish line in flight.


black-necked stilt

black-necked stilt

The Black-necked Stilt (Himantopus mexicanus) is a locally abundant shorebird of American wetlands and coastlines. It is found from the coastal areas of California through much of the interior western United States and along the Gulf of Mexico as far east as Florida, then south through Central America and the Caribbean to northwest Brazil southwest Peru,east Ecuador and the Galápagos Islands. The northernmost populations, particularly those from inland, are migratory, wintering from the extreme south of the United States to southern Mexico, rarely as far south as Costa Rica; on the Baja California peninsula it is only found regularly in winter.It is often treated as a subspecies of the Common or Black-winged Stilt, using the trinomial name Himantopus himantopus mexicanus.However, the AOU has always considered it a species in its own right, and the scientific name Himantopus mexicanus is often seen. Matters are more complicated though; sometimes all five distinct lineages of the Common Stilt are treated as different species. But the White-necked Stilt from southern South America (H. h. melanurus when only one species is recognized), parapatric and intergrading to some extent with its northern relative where their ranges meet, would warrant inclusion with the Black-necked stilt when this is separated specifically, becoming Himantopus mexicanus melanurus. Similarly, the Hawaiian Stilt, H. h. knudseni, is likely to belong to the American species when this is considered separate; while some treat it as another distinct species, the AOU, BirdLife International and the IUCN do not.Thus, in their scheme the Black-necked Stilt is properly named Himantopus mexicanus mexicanus.

Thursday, 15 December 2011

Roseate Spoonbill

Roseate Spoonbill

The Roseate Spoonbill, Platalea ajaja, (sometimes placed in its own genus Ajaja) is a gregarious wading bird of the ibis and spoonbill family, Threskiornithidae. It is a resident breeder in South America mostly east of the Andes, and in coastal regions of the Caribbean, Central America, Mexico, and the Gulf Coast of the United States.A 2010 study of mitochondrial DNA of the spoonbills by Chesser and colleagues found that the Roseate and Yellow-billed Spoonbills were each others' closest relative, and the two were descended from an early offshoot from the ancestors of the other four spoonbill species. They felt the genetic evidence meant it was equally valid to consider all six to be classified within the genus Platalea or alternatively the two placed in the monotypic genera Platibis and Ajaja respectively. However, as the six species were so similar morphologically, keeping them within the one genus made more sense.The Roseate Spoonbill is 71–86 cm (28–34 in) long, with a 120–130 cm (47–51 in) wingspan and a body mass of 1.2–1.8 kg (2.6–4.0 lb).It has long legs, a long neck, and a long, spatulate bill. Adults have a bare greenish head ("golden buff" when breeding) and a white neck, back, and breast (with a tuft of pink feathers in the center when breeding), and are otherwise a deep pink. The bill is grey. There is no significant sexual dimorphism.
Like the American Flamingo, their pink color is diet-derived, consisting of the carotenoid pigment canthaxanthin. Another carotenoid, astaxanthin, can also be found deposited in flight and body feathers. The colors can range from pale pink to bright magenta, depending on age and location. Unlike herons, spoonbills fly with their necks outstretched. They alternate groups of stiff, shallow wingbeats with glides.