Long-winged harrier | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Accipitriformes |
Family: | Accipitridae |
Genus: | Circus |
Species: | C. buffoni |
Binomial name | |
Circus buffoni (Gmelin, JF, 1788) | |
Nonbreeding Breeding Year-round |
The long-winged harrier (Circus buffoni) is a common bird of prey species endemic to South America. They are members of the family Accipitridae, under the genus Circus which encompasses other harrier species. Its range encompasses most of South America, in grassland and wetland all across the continent. The long-winged harrier is a carnivorous bird, and will feed on many different animals found in its habitat. Like owls and other harrier species, the long-winged harrier has a distinctive facial disc, which is used to triangulate the bird's hearing while it is hunting.
The long-winged harrier is classified as a species of least concern by the IUCN Red List, however their population has been observed to decline due to habitat degradation by human activity.
The long-winged harrier was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae . He placed it with the falcons, eagles and their relatives in the genus Falco and coined the binomial name Falco buffoni. [2] Gmelin based his description on the "Cayenne ringtail" that had been described in 1781 by the English ornithologist John Latham in his multi-volume work A General Synopsis of Birds. Latham had examined a specimen from Cayenne that formed part of a private collection in London. The specimen had been given the title "Duc de Buffon". [3] The long-winged harrier is now one of 16 harriers placed in the genus Circus that was introduced in 1799 by the French naturalist Bernard Germain de Lacépède. [4] [5] The genus name Circus is derived from the Ancient Greek kirkos, referring to a bird of prey named for its circling flight (kirkos, "circle"), probably the hen harrier. The specific epithet buffoni is from the name of the French naturalist, the Comte de Buffon. [6] The long-winged harrier does not have any recognised subspecies. [5]
The long-winged is mid-sized bird of prey, and like most birds of prey species, the females are larger than the males. Males will weigh from 390 to 464 g (13.8 to 16.4 oz) and females will be slightly heavier, ranging from 400 to 645 g (14.1 to 22.8 oz). [7] Their length can range between 46 and 60 cm (18 and 23.5 in) and their wingspan ranges between 120 and 155 cm (47 and 61 in). [7] As other harrier species, the lon-winged harrier can be identified by its long and narrow tail and its especially long wings. [8] Their wings and their back are mostly grey, with the primary feathers on the wings being much darker than the rest of the wing feathers, which are streaked with variants of white, grey and brown. [9]
The long-winged harrier can arbor 2 different morphs, a dark morph and a light morph. In dark morph individuals, the belly is all black with females having more of a brown undertone. [10] The light morph individuals can be identified by their white underparts, which contrasts heavily with their dark morph counterpart. [10] Juvenile long-winged harriers usually have the same colour patterns as females, but they have a more speckled chest. [11] The long-winged harrier morphologically resembles its close relative, the cinereous harrier (Circus cinereus), which can also be found in South America, but their range rarely overlaps.
As all other birds of prey species, the long-winged harrier possesses sharp talons used to catch their prey on the ground or in the air, and their legs are bright orange. The species also shares the large hooked beak of other birds of prey, which it uses to tear apart meat once it catches its prey.
The long-winged harrier is part of the only diurnal bird of prey group to possess a facial disc. The facial disc is formed by a group of easily recognizable group of feathers that form a disc shape around the bird's face. [12] These feathers can be raised in response to sounds and can improve the bird's hearing when it is hunting by triangulating sounds in its ear holes. [12]
Little is known of the long-winged harrier's vocalization, as is not a very vocal bird. It will call mostly when in flight and some variation of the bird's call include a fast succession of "klee-klee-klee", and a more quiet "thrill" with a quickly descending pitch.
The long-winged harrier's year-round range encompasses most of eastern South America, including eastern Argentina, Uruguay, Brazil and Paraguay, and extends up to Colombia, Venezuela, and the northern tips of Guyana, Suriname and French Guiana. [10] [13] The species has also been observed occasionally in extant areas such as Bolivia, Peru, Chile, Trinidad and Tobago, and all the way down to Tierra del Fuego in southern Argentina. [10] [13] [11] It is vagrant to Panama and the Falkland Islands. [14]
This species occupies large grasslands and agricultural fields, where their wide-range active hunting technique is very effective. Their habitat also includes savanna, marshes and wetlands of South America.
As all of the extended members of the family Accipitridae, the long-winged harrier is carnivorous, feeding on a large variety of animals due to its widespread distribution. Their diet includes small mammals (such as cavies), amphibians (such as frogs), reptiles (such as lizards) and birds (such as crakes and young coots), with birds consisting the majority of their food intake. [15] [16] It will also feed on bird eggs, varying from taking the whole ball-nests of water-tyrants to raiding heronries. [16] Its hunting strategy differs vastly from other hawks sharing the same habitat such as the roadside hawk (Rupornis magnirostris). [17] Instead of opting for a passive hunting strategy consisting of the use of high perches to locate their prey, the long-winged harrier will fly slowly in large circles above its range in order to find its prey, using its keen vision and hearing. [17]
The long-winged harrier nests on the ground, building its nest between September and October in the grasslands of its habitat. [18] The nests are usually made out of rushes and grass, and are built no more than 3 meters up the ground and no less than 1 meter away from bodies of water. [19] Their breeding season can vary vastly across their range, but it will usually take place in the summer months (September to January). During their reproduction cycle, the nests will usually hold between 3 and 4 eggs per clutch. [18]
Although the species population has been found to be declining, the extended range of the long-winged harrier allows it to be classified as a species of 'least concern' by the IUCN Red List. [14] Their population decline has been attributed to the degradation of its habitat, most notably wetlands, due to drainage, pollution, and other human-caused circumstances. [8] No conservation efforts are currently in action concerning the long-winged harrier as an individual species, but their range occurs in a wide variety of conservation sites and protected areas. [14]
A harrier is any of the several species of diurnal hawks sometimes placed in the subfamily Circinae of the bird of prey family Accipitridae. Harriers characteristically hunt by flying low over open ground, feeding on small mammals, reptiles, or birds. The young of the species are sometimes referred to as ring-tail harriers. They are distinctive with long wings, a long narrow tail, the slow and low flight over grasslands and skull peculiarities. The harriers are thought to have diversified with the expansion of grasslands and the emergence of C4 grasses about 6 to 8 million years ago during the Late Miocene and Pliocene.
The palm-nut vulture or vulturine fish eagle, is a large bird of prey in the family Accipitridae. It is the only member of the genus Gypohierax.
The hen harrier is a bird of prey. It breeds in Eurasia. The term "hen harrier" refers to its former habit of preying on free-ranging fowl.
Montagu's harrier (Circus pygargus) is a migratory bird of prey of the harrier family. Its common name commemorates the British naturalist George Montagu.
The northern harrier, also known as the marsh hawk or ring-tailed hawk, is a bird of prey. It breeds throughout the northern parts of the northern hemisphere in Canada and the northernmost USA.
The short-toed snake eagle, also known as the short-toed eagle, is a medium-sized bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as kites, buzzards and harriers. The genus name Circaetus is from the Ancient Greek kirkos, a type of hawk, and aetos, "eagle". The specific gallicus means "of Gallia".
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The roadside hawk is a relatively small bird of prey found in the Americas. This vocal species is often the most common raptor in its range. It has many subspecies and is now usually placed in the monotypic genus Rupornis instead of Buteo.
The cinereous harrier is a South American bird of prey of the harrier family. Its breeding range extends from the Tierra del Fuego through Argentina and Chile to Bolivia, Paraguay, Peru and southern Brazil; and across the Andes north to Colombia. The bird's population is declining but due to its large range is not considered vulnerable. The term cinereous, deriving from the Latin word for ashy, describes its colouration.
The Papuan eagle is a large bird of prey. It is also known by several other names, including Papuan harpy eagle, New Guinea eagle, New Guinea harpy eagle, or kapul eagle, the latter name from the local name for a usually arboreal, marsupial that the eagle is known to regularly hunt. This is an endemic species to New Guinea, and it can occasionally be found throughout the island. This is a forest-dwelling species, usually occurring in mature rainforest. The Papuan eagle is a fairly little-known species for a large eagle; however, it is known to prey on a wide range of prey, probably by and large mammals and birds from small to quite large sizes. What little study has been conducted about their breeding habits suggests they nest in a large forest tree, perhaps every other year. The Papuan eagle is probably naturally scarce, but it is under the threat of habitat destruction by deforestation, as well as hunting. Due to its small and declining population, the species has been classified as vulnerable by the IUCN.
The grey-faced buzzard is an Asian bird of prey. It is typically 41–46 cm (16–18 in) in length, making it a small-sized raptor. It breeds in Manchuria, Korea and Japan; it winters in South-east Asia.
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The grey goshawk is a strongly built, medium-sized bird of prey in the family Accipitridae that is found in eastern and northern Australia. The white morph of this species is known as the white goshawk.
The upland buzzard is a species of bird of prey in the family Accipitridae. The largest species of the Buteo genus, this buzzard lives in mountainous grassy and rocky areas in areas of Central Asia, northern South Asia and East Asia from Kazakhstan to Korea. The upland buzzard is migratory but typically covers a short distance apparently to avoid snow cover that may hamper prey capture. This species primarily subsists on small mammals but does not shun alternate prey from small to large birds and insects. This little known raptor has a large range, and though generally uncommon, it is not thought to be rare or declining as a species. As a result it is classified as least concern by the IUCN.
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The red-shouldered hawk is a medium-sized buteo. Its breeding range spans eastern North America and along the coast of California and northern to northeastern-central Mexico. It is a permanent resident throughout most of its range, though northern birds do migrate, mostly to central Mexico. The main conservation threat to the widespread species is deforestation.