The Spot-billed Pelican or Grey Pelican (Pelecanus philippensis) 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. 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.
Description
The Spot-billed Pelican is a relatively small pelican but still a
large bird. It is 125–152 cm (49–60 in) long and a weight of 4.1–6 kg
(9-13.2 lbs). 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.
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.
Distribution and population
Pelecanus philippensis was formerly common across much of Asia, but suffered a widespread decline (BirdLife International 2001). However, owing to protection and increased knowledge its estimated population has been revised upwards from a low of 5,500-10,000 birds in 2002 to an estimated 13,000-18,000 individuals in 2006. Known breeding populations are now confined to India, Sri Lanka and Cambodja . The Indian population is thought to exceed 5,000 birds in the south owing to increases resulting from improved protection of the species (S. Subramanya in litt. 2006), plus c.3,000 in Assam (Choudhury 2000). In southern India there are 21 known breeding colonies in the states of Andhra Pradesh, Karnataka and Tamil Nadu (Subramanya 2006). One of these at Kokkare Bellur, Karnataka, has doubled in size in recent years (Subramanya 2006). However, another at Uppalapadu has declined from a historical high of 12,000 individuals, with only 1,500 observed in a recent count. The site is threatened by human encroachment (M. Akhtar in litt. 2008). In Sri Lanka, c.5,000 birds were thought to breed, possibly overlapping with the southern Indian populations (S. W. Kotagama in litt. 2001). However, recent evidence from Sri Lanka suggests a breeding population of fewer than 1,000 pairs, with counts from the three known colonies totalling just 400 pairs (C. Kaluthota in litt. 2006). In South-East Asia, an estimated 1,000-1,500 breeding pairs (T. Clements in litt. 2007) occur at Prek Toal on the Tonle Sap lake. This population is thought to be increasing following protection of breeding birds at the site beginning in 2002 (T. Clements in litt. 2007). It probably breeds in small numbers on Sumatra, Indonesia, but probably no longer in Myanmar (G. Chunkino in litt. 2006, Weerakoon and Athukorala 2007). There are recent records of migrants in Nepal, Laos and Vietnam, but it no longer occurs in the Philippines and China. Numbers recorded in Thailand have increased in recent years (P. Round in litt. 2006). This is thought to be as a result of improved protection of the nesting colonies in Cambodia. A juvenile, presumably a vagrant, individual has recently been recorded on Amami-Oshima Island, Japan (Hisahiro et al. 2010).
Pelecanus philippensis was formerly common across much of Asia, but suffered a widespread decline (BirdLife International 2001). However, owing to protection and increased knowledge its estimated population has been revised upwards from a low of 5,500-10,000 birds in 2002 to an estimated 13,000-18,000 individuals in 2006. Known breeding populations are now confined to India, Sri Lanka and Cambodja . The Indian population is thought to exceed 5,000 birds in the south owing to increases resulting from improved protection of the species (S. Subramanya in litt. 2006), plus c.3,000 in Assam (Choudhury 2000). In southern India there are 21 known breeding colonies in the states of Andhra Pradesh, Karnataka and Tamil Nadu (Subramanya 2006). One of these at Kokkare Bellur, Karnataka, has doubled in size in recent years (Subramanya 2006). However, another at Uppalapadu has declined from a historical high of 12,000 individuals, with only 1,500 observed in a recent count. The site is threatened by human encroachment (M. Akhtar in litt. 2008). In Sri Lanka, c.5,000 birds were thought to breed, possibly overlapping with the southern Indian populations (S. W. Kotagama in litt. 2001). However, recent evidence from Sri Lanka suggests a breeding population of fewer than 1,000 pairs, with counts from the three known colonies totalling just 400 pairs (C. Kaluthota in litt. 2006). In South-East Asia, an estimated 1,000-1,500 breeding pairs (T. Clements in litt. 2007) occur at Prek Toal on the Tonle Sap lake. This population is thought to be increasing following protection of breeding birds at the site beginning in 2002 (T. Clements in litt. 2007). It probably breeds in small numbers on Sumatra, Indonesia, but probably no longer in Myanmar (G. Chunkino in litt. 2006, Weerakoon and Athukorala 2007). There are recent records of migrants in Nepal, Laos and Vietnam, but it no longer occurs in the Philippines and China. Numbers recorded in Thailand have increased in recent years (P. Round in litt. 2006). This is thought to be as a result of improved protection of the nesting colonies in Cambodia. A juvenile, presumably a vagrant, individual has recently been recorded on Amami-Oshima Island, Japan (Hisahiro et al. 2010).
Behaviour
They are very silent although at their nests they can make hisses, grunts or snap their bills.
Some early descriptions of nesting colonies have claimed them to be
distinctive in their silence but most have noted colonies as noisy.
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.They may forage at night to some extent.
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.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.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. Eggs hatch in about 30–33 days. The young stay in or near the nest from three to five months. In captivity the young are able to breed after two years. Like other pelicans, they cool themselves using gular fluttering and panting.
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