Greater Adjutant
Encyclopedia
The Greater Adjutant is a member of the stork
Stork
Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family Ciconiidae. They are the only family in the biological order Ciconiiformes, which was once much larger and held a number of families....

 family, Ciconiidae. Its genus includes the Lesser Adjutant
Lesser Adjutant
The Lesser Adjutant, Leptoptilos javanicus, is a large wading bird in the stork family Ciconiidae. It is a widespread species which is resident breeder in southern Asia from India east to southern China and Java....

 of Asia and the Marabou Stork
Marabou Stork
The Marabou Stork, Leptoptilos crumeniferus, is a large wading bird in the stork family Ciconiidae. It breeds in Africa south of the Sahara, occurring in both wet and arid habitats, often near human habitation, especially waste tips...

 of Africa. Once found widely across southern Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

, mainly in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 but extending east to Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....

, the Greater Adjutant is now restricted to a much smaller range with only two small breeding populations; in India with the largest colony in Assam
Assam
Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...

 and the other in Cambodia
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...

. Populations disperse after the breeding season. This large stork has a massive wedge-shaped bill, a bare head and a distinctive neck pouch. During the day, they soar in thermals along with vultures with whom they share the habit of scavenging. They feed mainly on carrion and offal; however, they are opportunistic and will sometimes prey on vertebrates. The English name is derived from their stiff "military" gait when walking on the ground. Large numbers once lived in Asia, but have declined greatly, possibly due to improved sanitation, to the point of being endangered. The total population in 2008 was estimated at around a thousand individuals. In the 19th century, they were especially common in the city of Calcutta, where they were referred to as the "Calcutta Adjutant". Known locally as Hargila (derived from the Sanskrit
Sanskrit
Sanskrit , is a historical Indo-Aryan language and the primary liturgical language of Hinduism, Jainism and Buddhism.Buddhism: besides Pali, see Buddhist Hybrid Sanskrit Today, it is listed as one of the 22 scheduled languages of India and is an official language of the state of Uttarakhand...

 word for "bone-swallower") and considered to be unclean birds, they were largely left undisturbed but sometimes hunted for the use of their meat in folk medicine
Folk medicine
-Description:Refers to healing practices and ideas of body physiology and health preservation known to a limited segment of the population in a culture, transmitted informally as general knowledge, and practiced or applied by anyone in the culture having prior experience.All cultures and societies...

. Valued as scavengers, they were once used in the logo of the Calcutta Municipal Corporation.

Description

The Greater Adjutant is a huge bird, standing tall at 150 cm (57–60 in). The average length is 136 cm (53.5 in) and average wingspan is 250 cm (99 in). While no weights have been published for wild birds, the Greater Adjutant is along with the Jabiru
Jabiru
The Jabiru is a large stork found in the Americas from Mexico to Argentina, except west of the Andes. It is most common in the Pantanal region of Brazil and the Eastern Chaco region of Paraguay. It is the only member of the genus Jabiru...

, Saddle-billed Stork
Saddle-billed Stork
The Saddle-billed Stork is a large wading bird in the stork family, Ciconiidae. It is a widespread species which is a resident breeder in sub-Saharan Africa from Sudan, Ethiopia and Kenya south to South Africa, and in The Gambia, Senegal, Côte d'Ivoire and Chad in west Africa.This is a close...

 and Marabou Stork
Marabou Stork
The Marabou Stork, Leptoptilos crumeniferus, is a large wading bird in the stork family Ciconiidae. It breeds in Africa south of the Sahara, occurring in both wet and arid habitats, often near human habitation, especially waste tips...

 among the largest and heaviest of storks. The average bill length is over 32 cm (12.6 in), which is the largest bill for an extant bird outside of the pelican family. The record wingspan was reportedly 3.28 m (10.8 ft). Juvenile storks of this species in captivity weighed from 8 to 11 kg (17.6 to 24.3 lb). The huge bill is wedge-like and is pale grey with a darker base. A white collar ruff at the base of its bare yellow to red-skinned neck gives it a vulture-like appearance. In the breeding season, the pouch and neck become bright orange and the upper thighs of the grey legs turn reddish. Adults have a dark wing that contrasts with light grey secondary coverts. The underside of the body is whitish and the sexes are indistinguishable in the field. Juveniles are a duller version of the adult. The pendant inflatable pouch connects to the air passages and is not connected to the digestive tract. The exact function is unknown, but it is not involved in food storage as was sometimes believed. The only confusable species in the region is the Lesser Adjutant
Lesser Adjutant
The Lesser Adjutant, Leptoptilos javanicus, is a large wading bird in the stork family Ciconiidae. It is a widespread species which is resident breeder in southern Asia from India east to southern China and Java....

, which lacks a pouch, prefers wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

 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, has a lighter grey skull cap, a straighter edge to the upper mandible and lacks the contrast between the grey secondary coverts and the dark wings.

Like others storks, it lacks vocal muscles and produces sound mainly by bill-clattering, although low grunting, mooing or roaring sounds are made especially when nesting. The bill-clattering display is made with the bill raised high and differs from that of the closely related African Marabou which holds the bill pointed downwards.

Taxonomy and systematics

John Latham
John Latham (ornithologist)
John Latham was an English physician, naturalist and author. He was born at Eltham in Kent, and was the eldest son of John Latham, a surgeon there, and his mother was a descendant of the Sothebys, in Yorkshire....

 wrote about the bird found in Calcutta based on descriptions in Ives's "Voyage to India" published in 1773 and included an illustration in the first supplement to his "General Synopsis of Birds". The illustration was based on a drawing in Lady Impey's collection and Latham called it the Gigantic Crane and included observations by an African traveller named Smeathman who described a similar bird from western Africa. Johann Friedrich Gmelin
Johann Friedrich Gmelin
Johann Friedrich Gmelin was a German naturalist, botanist, entomologist, herpetologist and malacologist.- Education :Johann Friedrich Gmelin was born as the eldest son of Philipp Friedrich Gmelin in 1748 in Tübingen...

 used Latham's description and described the Indian bird as Ardea dubia in 1789 while Latham later used the name Ardea argala for the Indian bird. Temminck
Coenraad Jacob Temminck
Coenraad Jacob Temminck was a Dutch aristocrat and zoologist.Temminck was the first director of the National Natural History Museum at Leiden from 1820 until his death. His Manuel d'ornithologie, ou Tableau systematique des oiseaux qui se trouvent en Europe was the standard work on European birds...

 used the name Ciconia marabou in 1824 based on the local name used in Senegal for the African bird and this was also applied to the Indian species. This led to considerable confusion between the African and Indian species. The Marabou Stork
Marabou Stork
The Marabou Stork, Leptoptilos crumeniferus, is a large wading bird in the stork family Ciconiidae. It breeds in Africa south of the Sahara, occurring in both wet and arid habitats, often near human habitation, especially waste tips...

 of Africa looks somewhat similar but their disjunct distribution ranges, differences in bill structure, plumage, and display behaviour support their treatment as separate species.

Most storks fly with their neck outstretched, but the three Leptoptilos
Leptoptilos
Leptoptilos is a genus of very large tropical storks. Two species are resident breeders in southern Asia, and the Marabou Stork is found in sub-Saharan Africa....

species retract their neck in flight as heron
Heron
The herons are long-legged freshwater and coastal birds in the family Ardeidae. There are 64 recognised species in this family. Some are called "egrets" or "bitterns" instead of "heron"....

s do, possibly due to the heavy bill. When walking on the ground, it has a stiff marching gait from which the name "adjutant
Adjutant
Adjutant is a military rank or appointment. In some armies, including most English-speaking ones, it is an officer who assists a more senior officer, while in other armies, especially Francophone ones, it is an NCO , normally corresponding roughly to a Staff Sergeant or Warrant Officer.An Adjutant...

" is derived.

Distribution

This species was once widespread in the riverine plains of northern India, however their breeding areas were largely unknown for a long time until a very large nesting colony was finally discovered in 1877 at Shwaygheen on the Sittaung River, Pegu, Burma and it was believed that the Indian birds bred there. This breeding colony, which also included Spot-billed Pelican
Spot-billed Pelican
The Spot-billed Pelican or Grey Pelican is a member of the pelican family. It breeds in southern Asia from southern Pakistan across India east to Indonesia. It is a bird of large inland and coastal waters, especially large lakes...

s, declined in size and entirely vanished by the 1930s. Subsequently, a nest site in Kaziranga
Kaziranga National Park
Kaziranga National Park is a national park in the Golaghat and Nagaon districts of the state of Assam, India. A World Heritage Site, the park hosts two-thirds of the world's Great One-horned Rhinoceroses. Kaziranga boasts the highest density of tigers among protected areas in the world and was...

 was the only known breeding area until new sites were discovered in Assam, the Tonle Sap lake
Tonlé Sap
The Tonlé Sap is a combined lake and river system of major importance to Cambodia.The Tonlé Sap is the largest freshwater lake in South East Asia and is an ecological hot spot that was designated as a UNESCO biosphere in 1997....

 and in the Kulen Promtep Wildlife Sanctuary
Kulen Promtep Wildlife Sanctuary
The Kulen Promtep Wildlife Sanctuary is the largest protected area in Cambodia and was set aside to protect the critically endangered, possibly extinct Kouprey. It is located in the northern plains of Cambodia, near the border to Thailand....

. In 1989, the breeding population in Assam was estimated at about 115 birds and between 1994 and 1996 the population in the Brahmaputra valley was considered to be about 600. A small colony with about 35 nests was discovered near Bhagalpur
Bhagalpur
Bhagdattpuram was one of the most influential towns in "Aryavarta" . It is supposed to have been concurrent to Patliputra or Patna. Bhagdattpuram finds its mention in the Vedas and Ramayana as well. It is supposed to be the kingdom of Daanvir Karna, the son of Kunti and the Sun God...

 in 2006.

During the non-breeding season, storks in the Indian region disperse widely, mainly in the Gangetic Plains
Indo-Gangetic plain
The northern Plains also known as the Indo - Gangetic Plain and The North Indian River Plain is a large and fertile plain encompassing most of northern and eastern India, the most populous parts of Pakistan, parts of southern Nepal and virtually all of Bangladesh...

 and records from the Deccan region are rare. Records of flocks from further south near Mahabalipuram have been questioned. In the 1800s, Adjutant Storks were extremely common within the city of Calcutta during the summer and rainy season. These aggregations along the Ghat
Ghat
Ghat is the capital of the Ghat District in the Fezzan region of southwestern Libya.-History:In historical times, Ghat was a major terminal point on the Trans-Saharan trade route and a major administrative center in the Fezzan...

s of Calcutta however declined and vanished altogether by the early 1900s. Improved sanitation has been suggested as a cause of their decline. Birds were recorded in Bangladesh in the 1850s, breeding somewhere in the Sundarbans, but have not been recorded subsequently.

Behaviour and ecology

The Greater Adjutant is usually seen singly or in small groups as it stalks about in shallow lakes or drying lake beds and garbage dumps. It is often found in the company of kites
Kite (bird)
Kites are raptors with long wings and weak legs which spend a great deal of time soaring. Most feed mainly on carrion but some take various amounts of live prey.They are birds of prey which, along with hawks and eagles, are from the family Accipitridae....

 and vultures and will sometimes sit hunched still for long durations. They may also hold their wings outstretched, presumably to control their temperature. They soar on thermals using their large outstretched wings.

Breeding

The Greater Adjutant breeds during winter in colonies that may include other large waterbirds such as the Spot-billed Pelican
Spot-billed Pelican
The Spot-billed Pelican or Grey Pelican is a member of the pelican family. It breeds in southern Asia from southern Pakistan across India east to Indonesia. It is a bird of large inland and coastal waters, especially large lakes...

. 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 a large platform of twigs placed at the end of a near-horizontal branch of a tall tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

. Nests are rarely placed in forks and an unobstructed top canopy allows the birds to fly easily from and to the nests. In the Nagaon nesting colony in Assam, tall Alstonia scholaris
Alstonia scholaris
Alstonia scholaris Alstonia scholaris Alstonia scholaris (Apocynaceae, commonly called Blackboard tree, Indian devil tree, Ditabark, Milkwood pine, White cheesewood and Pulai; syn. Echites scholaris L. Mant., Pala scholaris L...

and Anthocephalus cadamba were favourite nest trees. The beginning of the breeding season is marked by several birds congregating and trying to occupy a tree. While crowding at these sites, male birds mark out their nesting territories, chasing away others and frequently pointing their bill upwards while clattering them. They may also arch their body and hold their wings half open and drooped. When a female perches nearby, the male plucks fresh twigs and places it before her. The male may also grasp the tarsus of the female with the bill
Beak
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...

 or hold his bill close to her in a preen
Preen
- Birds :*Preen, personal grooming of a bird's feathers especially by using its beak*Preen gland, also called the uropygial gland, an oil gland found in many bird species*Preen oil, an oil made by the uropygial gland found in many bird species...

ing gesture. A female that has paired holds the bill and head to the breast of the male and the male locks her by holding his bill over her neck. Other displays include simultaneous bill raising and lowering by a pair. The clutch
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...

, usually of 3 or 4 white 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...

, is laid at intervals of one or two days and incubation
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...

 begins after the first egg is laid. Both parents incubate and the eggs hatch at intervals of one or two days, each taking about 35 days from the date of laying. Adults at the nest have their legs covered with their droppings and this behaviour termed as urohidrosis
Urohidrosis
Urohidrosis is the habit in some birds of defecating onto the scaly portions of the legs as a cooling mechanism, using evaporative cooling of the fluids. Several species of storks and New World vultures exhibit this behaviour. Birds' droppings consist of faeces and urine, which are excreted...

 is believed to aid in cooling during hot weather. Adults may also spread out their wings and shade the chicks. The chicks are fed at the nest for about five months.

Feeding

The Greater Adjutant is omnivorous and although mainly a scavenger, it sometimes preys on frog
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...

s and large insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s and will even take birds, reptiles and rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

s. It has been known to attack wild ducks coming within reach and swallowing them whole. Their main diet however is carrion
Carrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...

 and like the vultures their bare head and neck is an adaptation. They are often found on garbage dumps and will feed on animal and human excreta. In 19th Century Calcutta, they fed on partly burnt human corpses disposed along the Ganges river. In Rajasthan, where it is extremely rare, it has been reported to feed on swarms of the desert locust (Schistocerca gregaria) but this has been questioned.

Parasites, diseases and mortality

At least two species of bird lice, Colpocephalum cooki and Ciconiphilus temporalis have been found as ectoparasites. Healthy adult birds have no natural predators, and the only recorded causes of premature mortality are due to the direct or indirect human actions; such as, poisoning, shooting, or electrocution when the birds accidentally fly into overhead electricity wires. Captive birds have been found to be susceptible to avian influenza (H5N1
H5N1
Influenza A virus subtype H5N1, also known as "bird flu", A or simply H5N1, is a subtype of the influenza A virus which can cause illness in humans and many other animal species...

) and high mortality was noted at a facility in Cambodia, with two-thirds of infected birds dying. The longest recorded life span in captivity was 43 years.

Status and conservation

Loss of nesting and feeding habitat through the draining of wetlands, pollution and disturbance, together with hunting and egg collection in the past has caused a massive decline in the population of this species. The world population was estimated at less than 1,000 individuals in 2008. The Greater Adjutant is evaluated as Endangered on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...

 of Threatened Species.

Conservation measures have included attempts to breed them in captivity and to reduce fatalities to young at their natural nesting sites. Nearly 15% of the chicks are killed when they fall off the nests and die of starvation, so conservationists position nets below nests to prevent injuries to falling young and then raise these fallen birds in enclosures for about five months before releasing them to join their wild siblings.

In culture

In Victorian times the Greater Adjutant was known as the Gigantic Crane and later as the Asiatic Marabou. It was very common in Calcutta during the rainy season and large numbers could be seen at garbage sites and also standing on the top of buildings. Its local name hargila is derived from the Sanskrit hadda-gilla, which means "bone-swallower", and John Latham
John Latham (ornithologist)
John Latham was an English physician, naturalist and author. He was born at Eltham in Kent, and was the eldest son of John Latham, a surgeon there, and his mother was a descendant of the Sothebys, in Yorkshire....

 used it to give the species the binomial name, Ardea argala. At that time it was a belief that it was protected by the soul
Soul
A soul in certain spiritual, philosophical, and psychological traditions is the incorporeal essence of a person or living thing or object. Many philosophical and spiritual systems teach that humans have souls, and others teach that all living things and even inanimate objects have souls. The...

s of dead Brahmin
Brahmin
Brahmin Brahman, Brahma and Brahmin.Brahman, Brahmin and Brahma have different meanings. Brahman refers to the Supreme Self...

s. The birds in Calcutta city were considered as efficient scavengers and an act was passed to protect them anyone who killed the bird had to pay a fine of fifty rupees. The old emblem of the Calcutta Municipal Corporation included two Adjutant Storks facing each other. Captured birds, probably from Calcutta reached menageries in Europe during this period.

An Indian myth recorded by the Moghul emperor Babur
Babur
Babur was a Muslim conqueror from Central Asia who, following a series of setbacks, finally succeeded in laying the basis for the Mughal dynasty of South Asia. He was a direct descendant of Timur through his father, and a descendant also of Genghis Khan through his mother...

 was that a magic "snake-stone
Snake-Stones
Snake-stones also known as viper's stone, black stone, schwarze Stein, pierre noire, and piedrita negra or serpent-stone are animal bones, which are widely used and promoted as a treatment for snake bite in Africa, South America and Asia...

" existed inside the skull of the bird, being an antidote for all snake venoms and poisons. This "stone" was supposed to be extremely rare as it could only be obtained by a hunter with great skill, for the bird had to be killed without letting its bill touch the ground in which case the "stone" would evaporate instantly. Folk-medicine practitioners believed that a piece of stork flesh chewed daily with betel
Betel
The Betel is the leaf of a vine belonging to the Piperaceae family, which includes pepper and Kava. It is valued both as a mild stimulant and for its medicinal properties...

could cure leprosy.

Further reading

  • Adam, John. (1825) A description of the Ciconia Argala or Adjutant bird of Bengal. Trans. Med. Phys. Soc. I., Calcutta:240-248
  • Bhattacharjee, P. C. & Saikia, P. K. (1996) Conservation of Greater Adjutant Stork in Assam. Final Technical report. Unpublished WWF report.
  • Singha, H. (1998). "Ecology, biology and ethology of Greater Adjutant Stork Leptoptilos dubius (Gmelin) in Assam, India". Unpublished Ph. D. thesis. Aligarh Muslim University.

External links

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