The sickle-billed vanga (''Falculea palliata'') is a species of

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

in the

vanga The family Vangidae (from ''vanga'', Malagasy for the hook-billed vanga, ''Vanga curvirostris'') comprises a group of often shrike-like medium-sized birds distributed from Asia to Africa, including the vangas of Madagascar to which the family o ...

family Vangidae. It is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

within the genus ''Falculea''. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

. Its natural

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

s are tropical dry

forest A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...

s and tropical dry

shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally o ...

Taxonomy

The sickle-billed vanga was described by

Isidore Geoffroy Saint-Hilaire Isidore Geoffroy Saint-Hilaire (; 16 December 1805 – 10 November 1861) was a French zoologist and an authority on deviation from normal structure. In 1854 he coined the term ''éthologie'' (ethology). Biography He was born in Paris, the ...

in 1836, who also erected the genus ''Falculea'' to place it in. There are no subspecies. Like many members of the

family it was previously placed in another family by early scientists. In the case of this species it was placed with the crows and jays in

Corvidae Corvidae is a Cosmopolitan distribution, cosmopolitan Family (biology), family of Songbird, oscine passerine birds that contains the crows, ravens, Rook (bird), rooks, magpies, jackdaws, jays, treepies, choughs, and Nutcracker (bird), nutcrackers ...

by H. Gadow in the 1883 Catalogue of the British Museum. Within the Vangidae it seems that the closest relatives are the Bernier's vanga (''Oriolia bernieri''), the white-headed vanga (''Artamella virdis'') and the three species in the genus ''

Xenopirostris ''Xenopirostris'' is a genus of birds in the family Vangidae. They are all endemism, endemic to Madagascar. Species It contains the following species: References

Xenopirostris, Bird genera Endemic birds of Madagascar Taxa named by ...

''. It is thought that the sickle-billed vanga split from the white-headed vanga around 1.1 million years ago. The two species share similar plumage but are very different in size and bill shape, reflecting the wide plasticity in body shape and feeding ecology in the vanga

radiation In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes: * ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infr ...

. Both species, as well as their other close relatives, also share a unique intense black colouration in the mouth.

Description

The sickle-billed vanga is the largest of the vangas, measuring in length and weighing . The most striking feature is the

bill Bill(s) may refer to: Common meanings * Banknote, paper cash (especially in the United States) * Bill (law), a proposed law put before a legislature * Invoice, commercial document issued by a seller to a buyer * Bill, a bird or animal's beak Pl ...

, which is strongly decurved and measures and is blue-grey fading to ivory at the tip. The

plumage Plumage () is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, there can b ...

is striking, with a white head, breast and belly and the back, wings and tail being black with a blue sheen. The iris is brown and the orbital ring around the eye is black. The legs are strong and coloured dark grey to pale blue. There is no

sexual dimorphism Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

. Juveniles are similar to adults but the black feathers on the back and wings are tipped with buff.

Distribution and habitat

The sickle-billed vanga is endemic to Madagascar, where it is found throughout the western side of the island. It ranges from sea-level up to . It is found in

dry deciduous forest The tropical and subtropical dry broadleaf forest is a habitat type defined by the World Wide Fund for Nature and is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive ...

as well as thorn-forest. It can also be found in open savanna and in wooded areas around villages. The species is non-migratory. The species is common within its range and is protected by a number of national parks, including

Andohahela National Park The Andohahela National Park is situated in Anosy in the south-east of Madagascar. It is remarkable for the extremes of habitats that are represented within it. The park covers of the Anosy mountain range, the southernmost spur of the Malagasy H ...

Ankarafantsika National Park Ankarafantsika National Park is a national park near Andranofasika in the Boeny Region of Madagascar. The closest city is Majunga north of the park. Ankarafantsika is mostly tropical in climate type. The Sakalava people are the predominant ethn ...

, and

Berenty Reserve Berenty Reserve is a small private reserve, near Amboasary Sud, Anosy. It is situated along the Mandrare River, set in the semi-arid spiny forest ecoregion of the far south of Madagascar. For more than three decades the late primatologist Aliso ...

. As such it is evaluated as

Least Concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

by the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

Behaviour

Diet and feeding

The sickle-billed vanga is a social species, particularly in the tiding flea season when it can travel in groups of up to thirty birds while foraging for food and form roosting groups of over fifty birds. These flocks become smaller during the breeding season, but retain a small group of non-breeders that forage together over a wide area. They will form

mixed-species foraging flock A mixed-species feeding flock, also termed a mixed-species foraging flock, mixed hunting party or informally bird wave, is a flock (birds), flock of usually insectivorous birds of different species that join each other and move together while fora ...

s with the related white-headed vanga and the

crested drongo The crested drongo (''Dicrurus forficatus'') is a passerine bird in the family Dicruridae. It is black with a bluish-green sheen, a distinctive crest on the forehead and a forked tail. There are two subspecies; ''D. f. forficatus'' is endemic t ...

. The species feeds on a wide range of terrestrial invertebrates, including spiders, cockroaches, crickets, beetles, and worms. Small vertebrates, including

chameleon Chameleons or chamaeleons (Family (biology), family Chamaeleonidae) are a distinctive and highly specialized clade of Old World lizards with 200 species described as of June 2015. The members of this Family (biology), family are best known for ...

s and

gecko Geckos are small, mostly carnivorous lizards that have a wide distribution, found on every continent except Antarctica. Belonging to the infraorder Gekkota, geckos are found in warm climates. They range from . Geckos are unique among lizards ...

s, are also part of the diet and are also fed to nestlings. They generally feed in trees and particularly favour large branches, and will probe their long bill deep into holes and use it to lever off bark to get at concealed prey, occupying part of the niche usually filled by

woodpecker Woodpeckers are part of the bird family (biology), family Picidae, which also includes the piculets, wrynecks and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar and the extreme ...

s, which are absent from Madagascar (they do not fully fill the niche as they do not hammer the wood for prey).

Breeding

The sickle-billed vanga is apparently a seasonal breeder, with the season running from October to January in

in the north western part of the island. This coincides with the end of the dry season. The species is one of the vangas that has a

polyandrous Polyandry (; ) is a form of polygamy in which a woman takes two or more husbands at the same time. Polyandry is contrasted with polygyny, involving one male and two or more females. If a marriage involves a plural number of "husbands and wives ...

breeding system, where one female will mate with two or more males and all are responsible for raising the young. It is the female that engages in courtship displays, approaching the male and quivering her wings while holding the body in a horizontal posture. The male does not perform any display in return. Sickle-billed vangas are

territorial A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal. In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, ...

and the males in the group will defend the territory from rivals and from potential or actual predators. The

nest A nest is a structure built for certain animals to hold Egg (biology), eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of ...

is atypical for the family, consisting of a large untidy bowl of twigs, in diameter, situated off the ground in the fork of a tree. The inner structure is lined with more delicate material. It is constructed by both sexes, but more work is done by the female. The clutch consists of three or four

eggs An egg is an organic vessel in which an embryo begins to develop. Egg, EGG or eggs may also refer to: Biology * Egg cell, the female reproductive cell (gamete) in oogamous organisms Food * Eggs as food Places * Egg, Austria * Egg, Switzerland ...

, which are creamy white with mottling (particularly towards the larger end of the egg). Both sexes incubate the eggs, and feed and brood the chicks, but as with nest construction the female does more of the work than the males. The incubation period is 16 to 18 days, and chicks

fledge Fledging is the stage in a flying animal's life between egg, hatching or birth and becoming capable of flight. This term is most frequently applied to birds, but is also used for bats. For altricial birds, those that spend more time in vulnera ...

after 19 to 23 days.

References

{{Taxonbar, from=Q1193043 sickle-billed vanga Endemic birds of Madagascar sickle-billed vanga Taxonomy articles created by Polbot