Spot-billed pelican | |
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At Bannerghatta National Park | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Pelecanidae |
Genus: | Pelecanus |
Species: | P. philippensis |
Binomial name | |
Pelecanus philippensis Gmelin, 1789 | |
The spot-billed pelican (Pelecanus philippensis) or gray pelican is a member of the pelican family. It breeds in southern Asia from southern Iran across India east to Indonesia. It is a bird of large inland and coastal waters, especially large lakes. At a distance they are difficult to differentiate from other pelicans in the region although it is smaller but at close range the spots on the upper mandible, the lack of bright colours and the greyer plumage are distinctive. In some areas these birds nest in large colonies close to human habitations.
The spot-billed pelican was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae . He placed it with the other pelicans in the genus Pelecanus and coined the binomial name Pelecanus philippensis. [2] Gmelin based his description on "Le pélican des Philippines" that had been described and illustrated in 1760 by the French zoologist Mathurin Jacques Brisson. Brisson's specimen had been collected on the island of Luzon in the Philippines. [3] [4] The species is monotypic: no subspecies are recognised. [5]
The spot-billed pelican is a rather large water bird, often the largest or one of the largest native birds in the southern stretches of its range, albeit it is fairly small for a pelican. It is 125–152 cm (49–60 in) long and a weight of 4.1–6 kg (9.0–13.2 lb). The wingspan can vary from 213 to 250 cm (7 ft 0 in to 8 ft 2 in) while the typically large beak measured from 285 to 355 mm (11.2 to 14.0 in). [6] It is mainly white, with a grey crest, hindneck and a brownish tail. The feathers on the hind neck are curly and form a greyish nape crest. The pouch is pink to purplish and has large pale spots, and is also spotted on the sides of the upper mandible. The tip of the bill (or nail) is yellow to orange. In breeding plumage, the skin at the base of the beak is dark and the orbital patch is pink. In flight they look not unlike the Dalmatian pelican but the tertials and inner secondaries are darker and a pale band runs along the greater coverts. The tail is rounder. [7]
The newly hatched young are covered in white down. They then moult into a greyish speckled plumage. The spots on the bill appear only after a year. The full adult breeding plumage appears in their third year. [8]
The species is found to breed only in peninsular India, Sri Lanka and in Cambodia. A few birds from India are known to winter in the Gangetic plains but reports of its presence in many other parts of the region such as the Maldives, Pakistan and Bangladesh has been questioned. [7] The main habitat is in shallow lowland freshwaters. The spot-billed pelican is not migratory but are known to make local movements and are more widely distributed in the non-breeding season.
This species is a colonial breeder, often breeding in the company of other waterbirds. The nests are on low trees near wetlands and sometimes near human habitations. Many large breeding colonies have been recorded and several have disappeared over time. In June 1906, C E Rhenius visited a colony in Kundakulam in Tirunelveli district where the villages considered the birds semi-sacred. [9] The same colony was revisited in 1944, and was found to have about 10 nests of pelicans and nearly 200 nests of painted stork. [10]
The Sittang River in Burma was said by E W Oates to have "millions" of pelicans in 1877 and in 1929 E C Stuart Baker reported that they were still nesting in thousands along with greater adjutant storks:
The whole forest consisted of very large trees, but a portion, about one in twenty, was made up of wood-oil trees, gigantic fellows, 150 feet high and more, and with a smooth branchless trunk of 80 to 100 feet. These are the trees selected by the pelicans.
I was out that day till 3 p.m., continually moving, and must have walked at least twenty miles in various directions, but never from first to last was I out of sight of either a Pelican's or Adjutant's nest. From what I saw, and from what the Burmans told me, I compute the breeding-place of these birds to extend over an area about twenty miles long and five broad.
This colony was however reported by B E Smythies to have disappeared between the 1930s and the 1940s. [12]
Another colony was discovered in 1902 at a village called Buchupalle in the Cudappah district, where these pelicans nested along with painted storks during the month of March. [13] This colony was never traced again. [12] The Kolleru Lake colony was discovered by K K Neelakantan in 1946. Nearly 3000 pelicans nested in this colony at the time of discovery. [12] [14] This colony however disappeared around 1975. [15] [16] [17]
Due to habitat loss and human disturbance, the spot-billed pelican's numbers have declined and many populations in Southeast Asia (including parts of China [18] ) are now extinct. [19] The specific name refers to the Philippines, where the species was abundant in the early 1900s [8] but declined and become locally extinct in the 1960s. [20] The populations in southern India are thought to be on the rise. [21] Estimates suggest that increased protection has since enabled a recovery in their numbers and the status of the species was changed from vulnerable to near threatened in the 2007 IUCN Red List. [1]
They are very silent although at their nests they can make hisses, grunts or snap their bills. [7] Some early descriptions of nesting colonies have claimed them to be distinctive in their silence but most have noted colonies as noisy. [12] [22]
Like most other pelicans, it catches fish in its huge bill pouch while swimming at the surface. Unlike the great white pelican it does not form large feeding flocks and is usually found to fish singly or in small flocks. Groups may however sometimes line up and drive fish towards the shallows. When flying to their roosts or feeding areas, small groups fly in formation with steady flapping. During the hot part of the day, they often soar on thermals. [23] They may forage at night to some extent. [24]
The birds nest in colonies and the nest is a thick platform of twigs placed on a low tree. The breeding season varies from October to May. [7] In Tamil Nadu, the breeding season follows the onset of the northeast monsoon. The courtship display of the males involves a distention of the pouch with swinging motions of the head up and down followed by sideways swings followed by the head being held back over the back. Bill claps may also be produced during the head swaying movements. [25] [26] The nests are usually built alongside other colonial waterbirds, particularly painted storks. Three to four chalky white eggs is the usual clutch. The eggs become dirty with age. [23] Eggs hatch in about 30–33 days. The young stay in or near the nest from three to five months. [25] [27] In captivity the young are able to breed after two years. [28] Like other pelicans, they cool themselves using gular fluttering and panting. [29]
The trematode parasite Renicola pelecani was described from the kidneys of a specimen of a Sri Lankan spot-billed pelican that died at the London zoo. [30] [31]
This species was once used by fishermen in parts of eastern Bengal as decoys for certain fish. These fishermen believed that an oily secretion from the bird attracted certain fish such as Colisa and Anabas . [32]
The propensity of these birds to nest close to human habitations has been noted from the time of T C Jerdon:
I have visited on Pelicanry in the Carnatic, where the Pelicans have (for ages I was told) built their rude nests, on rather low trees in the midst of a village, and seemed to care little for the close and constant proximity of human beings.
— Jerdon, 1864 [32]
Several colonies have since been discovered and while many of these have vanished others have been protected and a few villages with nesting colonies have become popular tourist attractions. Well known villages with colonies include Kokrebellur, Koothankulam and Uppalapadu. [16] [33]
The American white pelican is a large aquatic soaring bird from the order Pelecaniformes. It breeds in interior North America, moving south and to the coasts, as far as Costa Rica, in winter.
The Dalmatian pelican is the largest member of the pelican family, and perhaps the world's largest freshwater bird, although rivaled in weight and length by the largest swans. They are elegant soaring birds, with wingspans rivaling those of the great albatrosses, and their flocks fly in graceful synchrony. With a range spanning across much of Central Eurasia, from the Mediterranean in the West to the Taiwan Strait in the East, and from the Persian Gulf in the South to Siberia in the North, it is a short-to-medium-distance migrant between breeding and overwintering areas. No subspecies are known to exist over its wide range, but based on size differences, a Pleistocene paleosubspecies, P. c. palaeocrispus, has been described from fossils recovered at Binagady, Azerbaijan.
The great white pelican also known as the eastern white pelican, rosy pelican or simply white pelican is a bird in the pelican family. It breeds from southeastern Europe through Asia and Africa, in swamps and shallow lakes.
The western reef heron, also called the western reef egret, is a medium-sized heron found in southern Europe, Africa and parts of Asia. It has a mainly coastal distribution and occurs in several plumage forms: a slaty-grey plumage in which it can only be confused with the rather uncommon dark morph of the Little egret ; a white form which can look very similar to the little egret although the bill tends to be paler and larger and the black form with white throat E. g. gularis of West Africa. There are also differences in size, structure and foraging behaviour. There have been suggestions that the species hybridizes with the Little Egret, and based on this, some authors treat schistacea and gularis as subspecies of Egretta garzetta. Works that consider the Western Reef Heron as a valid species include the nominate gularis and schistacea as subspecies.
The pheasant-tailed jacana is a jacana in the monotypic genus Hydrophasianus. Like all other jacanas, they have elongated toes and nails that enable them to walk on floating vegetation in shallow lakes, their preferred habitat. They may also swim or wade in water reaching their body while foraging mainly for invertebrate prey. They are found in tropical Asia from Yemen in the west to the Philippines in the east and move seasonally in parts of their range. They are the only jacanas that migrate long distances and have different non-breeding and breeding plumages. The pheasant-tailed jacana forages by swimming or by walking on aquatic vegetation. Females are larger than males and are polyandrous, laying several clutches that are raised by different males in their harem.
The shikra is a small bird of prey in the family Accipitridae found widely distributed in Asia and Africa where it is also called the little banded goshawk. The African forms may represent a separate species but have usually been considered as subspecies of the shikra. The shikra is very similar in appearance, as well as behavior, at least to some degree, to other species including the Chinese sparrowhawk, Eurasian goshawk and Eurasian sparrowhawk. They have a sharp two note call and have the typical flap and glide flight. Their calls are imitated by drongos and the common hawk-cuckoo resembles it in plumage. This species was formerly placed in the genus Accipiter.
The lesser adjutant is a large wading bird in the stork family Ciconiidae. Like other members of its genus, it has a bare neck and head. It is however more closely associated with wetland habitats where it is solitary and is less likely to scavenge than the related greater adjutant. It is a widespread species found from India through Southeast Asia to Java.
The black-necked stork is a tall long-necked wading bird in the stork family. It is a resident species across the Indian Subcontinent and Southeast Asia with a disjunct population in Australia. It lives in wetland habitats and near fields of certain crops such as rice and wheat where it forages for a wide range of animal prey. Adult birds of both sexes have a heavy bill and are patterned in white and irridescent blacks, but the sexes differ in the colour of the iris with females sporting yellow irises and males having dark-coloured irises. In Australia, it is known as a jabiru although that name refers to a stork species found in the Americas. It is one of the few storks that are strongly territorial when feeding and breeding.
The pied thrush is a member of the thrush family found in India and Sri Lanka. The males are conspicuously patterned in black and white while the females are olive brown and speckled. They breed in the central Himalayan forests and winter in the hill forests of southern India and Sri Lanka. Like many other thrushes, they forage on leaf litter below forest undergrowth and fly into trees when disturbed and sit still making them difficult to locate.
The painted stork is a large wader in the stork family. It is found in the wetlands of the plains of tropical Asia south of the Himalayas in the Indian Subcontinent and extending into Southeast Asia. Their distinctive pink tertial feathers of the adults give them their name. They forage in flocks in shallow waters along rivers or lakes. They immerse their half open beaks in water and sweep them from side to side and snap up their prey of small fish that are sensed by touch. As they wade along they also stir the water with their feet to flush hiding fish. They nest colonially in trees, often along with other waterbirds. The only sounds they produce are weak moans or bill clattering at the nest. They are not migratory and only make short-distance movements in some parts of their range in response to changes in weather or food availability or for breeding. Like other storks, they are often seen soaring on thermals.
The Asian openbill or Asian openbill stork is a large wading bird in the stork family Ciconiidae. This distinctive stork is found mainly in the Indian subcontinent and Southeast Asia. It is greyish or white with glossy black wings and tail and the adults have a gap between the arched upper mandible and recurved lower mandible. Young birds are born without this gap which is thought to be an adaptation that aids in the handling of snails, their main prey. Although resident within their range, they make long distance movements in response to weather and food availability.
The Indian nightjar is a small nightjar which is a resident breeder in open lands across South Asia and Southeast Asia. Like most nightjars it is crepuscular and is best detected from its characteristic calls at dawn and dusk that have been likened to a stone skipping on a frozen lake - a series of clicks that become shorter and more rapid. They are sometimes spotted on roads when their eyes gleam red in the spotlight of a vehicle. There is considerable plumage variation across its range and can be hard to differentiate from other nightjars in the region especially in the field.
The purple sunbird is a small bird in the sunbird family found mainly in South and Southeast Asia but extending west into parts of the Arabian peninsula. Like other sunbirds they feed mainly on nectar, although they will also take insects, especially when feeding young. They have a fast and direct flight and can take nectar by hovering like a hummingbird but often perch at the base of flowers. The males can appear all black in harsh sunlight but the purple iridescence is visible on closer observation or under good light conditions. Females are olive above and yellowish below.
The Indian robin is a species of passarine bird in the family Muscicapidae. It is widespread in the Indian subcontinent and ranges across Bangladesh, Bhutan, India, Nepal, Pakistan and Sri Lanka. The males of the northern subspecies have brown backs whose extent gradually reduces southwards, with the males of the southern subspecies having all-black backs. They are commonly found in open scrub areas and often seen running along the ground or perching on low thorny shrubs and rocks. The long tail is usually held up and the chestnut undertail coverts and dark body make them easily distinguishable from pied bushchats and Oriental magpie-robins.
The greater adjutant is a member of the stork family, Ciconiidae. Its genus includes the lesser adjutant of Asia and the marabou stork of Africa. Once found widely across southern Asia and mainland southeast Asia, the greater adjutant is now restricted to a much smaller range with only three breeding populations; two in India, with the largest colony in Assam and a smaller one around Bhagalpur; and another breeding population in Cambodia. They disperse widely after the breeding season. This large stork has a massive wedge-shaped bill, a bare head and a distinctive neck pouch. During the day, it soars in thermals along with vultures with whom it shares 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 they have declined to the point of endangerment. 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" and included in the coat of arms for the city. Known locally as hargila and considered to be unclean birds, they were largely left undisturbed but sometimes hunted for the use of their meat in folk medicine. Valued as scavengers, they were once depicted in the logo of the Calcutta Municipal Corporation.
The baya weaver is a weaverbird found across the Indian Subcontinent and Southeast Asia. Flocks of these birds are found in grasslands, cultivated areas, scrub and secondary growth and they are best known for their hanging retort shaped nests woven from leaves. These nest colonies are usually found on thorny trees or palm fronds and the nests are often built near water or hanging over water where predators cannot reach easily. They are widespread and common within their range but are prone to local, seasonal movements mainly in response to rain and food availability.
The painted francolin or painted partridge is a species of francolin found in grassy areas in central and southern India and in the lowlands of southeastern Sri Lanka. They are easily detected by their loud calls especially during the breeding season. Thomas C. Jerdon noted that the species was found mainly in Central India south of the Narmada and to the east of the Western Ghats as well as the Chota Nagpur and Northern Circars. It can be confused only with the black francolin with which it partly overlaps and is said to sometimes hybridize. This species can be told apart from a black francolin female by the lack of a rufous hind collar and the white spots on the underside. The face is rufous and there is no dark stripe running behind the eye.
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Kavassery Kailasam Neelakantan better known by his pen name Induchoodan, was a leading Indian ornithologist. He is widely regarded as a pioneer of the environmental movement in Kerala for popularizing bird study through his books written in Malayalam.
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