Sickle-billed Vanga
Encyclopedia
The Sickle-billed Vanga (Falculea palliata) is a species of bird
in the vanga
family Vangidae. It is monotypic
within the genus Falculea. It is endemic to Madagascar
. Its natural habitat
s are tropical dry forest
s and tropical dry shrubland
.
in 1836, who also erected the genus Falculea to place it in. There are no subspecies. Like many members of the vanga
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
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
. 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
. Both species, as well as their other close relatives, also share a unique intense black colouration in the mouth.
, which is strongly decurved and measures 77 mm (3 in) and is blue-grey fading to ivory at the tip. The plumage
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
. Juveniles are similar to adults but the black feathers on the back and wings are tipped with buff.
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 900 metres (2,952.8 ft). It is found in dry deciduous forest
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
, Ankarafantsika National Park
, and Berenty Reserve
. As such it is evaluated as Least Concern
by the IUCN.
and the Crested Drongo
. The species feeds on a wide range of terrestrial invertebrates, including spiders, cockroaches, crickets, beetles, and worms. Small vertebrates, including chameleon
s and gecko
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
s, which are absent from Madagascar (they do not fully fill the niche as they do not hammer the wood for prey).
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
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
and the males in the group will defend the territory from rivals and from potential or actual predators.
The nest
is atypical for the family, consisting of a large untidy bowl of twigs, 30 – in diameter, situated 9 – 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
, 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
after 19 to 23 days.
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
in the vanga
Vanga
The vangas are a group of little-known small to medium-sized passerine birds restricted to Madagascar and the Comoros. They are usually classified as the family Vangidae. There are about 22 species, depending on taxonomy...
family Vangidae. It is monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
within the genus Falculea. It is endemic to Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
. Its natural habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s are tropical dry forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s and tropical dry shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
.
Taxonomy
The Sickle-billed Vanga was described by Isidore Geoffroy Saint-HilaireIsidore Geoffroy Saint-Hilaire
Isidore Geoffroy Saint-Hilaire was a French zoologist and an authority on deviation from normal structure. He coined the term ethology.He was born in Paris, the son of Étienne Geoffroy Saint-Hilaire...
in 1836, who also erected the genus Falculea to place it in. There are no subspecies. Like many members of the vanga
Vanga
The vangas are a group of little-known small to medium-sized passerine birds restricted to Madagascar and the Comoros. They are usually classified as the family Vangidae. There are about 22 species, depending on taxonomy...
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
Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs and nutcrackers. The common English names used are corvids or the crow family , and there are over 120 species...
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
Bernier's Vanga
The Bernier's Vanga is a bird species in the family Vangidae. It is in the monotypic genus Oriolia. It is endemic to Madagascar. Its natural habitat is subtropical or tropical moist lowland forests. It is threatened by habitat loss.-References:* BirdLife International 2004. . Downloaded on 26...
(Oriolia bernieri), the White-headed Vanga
White-headed Vanga
The White-headed Vanga is a species of bird in the Vangidae family. It is monotypic within the genus Artamella. It is endemic to Madagascar....
(Artamella virdis) and the three species in the genus Xenopirostris
Xenopirostris
Xenopirostris is a genus of birds in the Vangidae family. They are all endemic to Madagascar.It contains the following species:* Van Dam's Vanga * Pollen's Vanga...
. 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
Evolutionary radiation
An evolutionary radiation is an increase in taxonomic diversity or morphological disparity, due to adaptive change or the opening of ecospace. Radiations may affect one clade or many, and be rapid or gradual; where they are rapid, and driven by a single lineage's adaptation to their environment,...
. 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, measureing 32 cm (12.6 in) in length and weighing 106 to 119 g (3.7 to 4.2 oz). The most striking feature is the billBeak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
, which is strongly decurved and measures 77 mm (3 in) and is blue-grey fading to ivory at the tip. The plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
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
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
. Juveniles are similar to adults but the black feathers on the back and wings are tipped with buff.
Distribution and habitat
Madagascar dry deciduous forests
The Madagascar dry deciduous forests represent a tropical dry forest ecoregion generally situated in the western part of Madagascar. The area has high numbers of endemic plant and animal species but has suffered large-scale clearance for agriculture...
as well as thorn-forest
Madagascar spiny thickets
The Madagascar spiny thickets is an ecoregion in Madagascar. The vegetation type is found on poor substrates with low, erratic winter rainfall. An estimated 14,000 to is covered with this habitat, all in the southwest of the country...
. 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
Andohahela National Park
Andohahela National Park, in southeast Madagascar, is remarkable for the extremes of habitats that are representened within it. The park covers 760 square kilometers of the Anosy mountain range, the southernmost spur of the Malagasy Highlands...
, Ankarafantsika National Park
Ankarafantsika National Park
Ankarafantsika National Park is a National Park in the Boeny Region of Madagascar. The closest city is Majunga 115 km north of the park. Ankarafantsika is mostly tropical in climate type. The Sakalava people are the predominate ethnic group in the park. The rodent Macrotarsomys ingens occurs only...
, and Berenty Reserve
Berenty Reserve
Berenty Reserve is a small private reserve of gallery forest along the Mandrake river, set in the semi-arid spiny forest ecoregion of the far south of Madagascar. For more than three decades the primatologist Alison Jolly , researchers and students have visited Berenty to conduct fieldwork on lemurs...
. As such it is evaluated as Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
by the IUCN.
Diet and feeding
The Sickle-billed Vanga is a social species, particularly in the non-breeding 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 flocks with the related White-headed VangaWhite-headed Vanga
The White-headed Vanga is a species of bird in the Vangidae family. It is monotypic within the genus Artamella. It is endemic to Madagascar....
and the Crested Drongo
Crested Drongo
The Crested Drongo is a species of bird in the Dicruridae family.It is found in Comoros, Madagascar, and Mayotte....
. The species feeds on a wide range of terrestrial invertebrates, including spiders, cockroaches, crickets, beetles, and worms. Small vertebrates, including chameleon
Chameleon
Chameleons are a distinctive and highly specialized clade of lizards. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a...
s and gecko
Gecko
Geckos are lizards belonging to the infraorder Gekkota, found in warm climates throughout the world. They range from 1.6 cm to 60 cm....
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
Woodpecker
Woodpeckers are near passerine birds of the order Piciformes. They are one subfamily in the family Picidae, which also includes the piculets and wrynecks. They are found worldwide and include about 180 species....
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 Ankarafantsika National ParkAnkarafantsika National Park
Ankarafantsika National Park is a National Park in the Boeny Region of Madagascar. The closest city is Majunga 115 km north of the park. Ankarafantsika is mostly tropical in climate type. The Sakalava people are the predominate ethnic group in the park. The rodent Macrotarsomys ingens occurs only...
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
Polyandry refers to a form of marriage in which a woman has two or more husbands at the same time. The form of polyandry in which a woman is married to two or more brothers is known as "fraternal polyandry", and it is believed by many anthropologists to be the most frequently encountered...
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
Territory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
and the males in the group will defend the territory from rivals and from potential or actual predators.
The nest
Bird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
is atypical for the family, consisting of a large untidy bowl of twigs, 30 – in diameter, situated 9 – 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
Bird egg
Bird eggs are laid by females and incubated for a time that varies according to the species; a single young hatches from each egg. Average clutch sizes range from one to about 17...
, which are creamy white with mottling (particularly towards the larger end of the egg). Both sexes incubate
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
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
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
after 19 to 23 days.