The Great White Pelican is a huge bird, with only the Dalmatian Pelican
averaging larger amongst the pelicans. The wingspan can from 226 to 360
cm (7.41 to 11.8 ft), with the latter measurement the largest recorded
among extant flying animals outside of the great albatrosses.
The total length of the Great White Pelican can range from 140 to 180
cm (55 to 71 in), with the enormous bill comprising 28.9 to 47.1 cm
(11.4 to 18.5 in) of that length. Adult males, weigh from 9 to 15 kg (20 to 33 lb), though large races from the Palaearctic are usually around 11 kg (24 lb) with few exceeding 13 kg (29 lb). Females are considerably less bulky and heavy, weighing from 5.4 to 9 kg (12 to 20 lb). Among standard measurements, the wing chord length is 60 to 73 cm (24 to 29 in), the tail is 16 to 21 cm (6.3 to 8.3 in) and the tarsus
is 13 to 14.9 cm (5.1 to 5.9 in). The standard measurements from
differing areas indicate that pelicans of the species from the Western Palaearctic are somewhat larger in size than ones that reside in Asia and in Africa.
Immature Great White Pelicans are grey and have dark flight feathers.
In flight, it is an elegant soaring bird, with the head held close to
and aligned with the body by a downward bend in the neck. In breeding
condition the male has pinkish skin on its face and the female has
orangey skin.
It differs from the Dalmatian Pelican by its pure white, rather than
greyish-white, plumage, a bare pink facial patch around the eye and
pinkish legs. Males are larger than females, and have a long beak that
grows in a downwards arc, as opposed to the shorter, straighter beak of
the female. The Spot-billed Pelican
of Asia is slightly smaller than the Great White, with clear
brownish-grey plumage and a paler, duller-colored bill. Similarly, the Pink-backed Pelican is smaller with brownish-grey plumage, with a light pink to off-grey bill and a pinkish wash to the back.
The Great White Pelican is well adapted for aquatic
life. The short strong legs and webbed feet propel it in water and aid
the rather awkward takeoff from the water surface. Once aloft, the
long-winged pelicans are powerful fliers, however, and often travel in
spectacular V-formation groups.
Habitat
The fishing technique of these birds demands the shallow, warm water of
lakes, deltas, marshes and swamps. In Europe and Asia the great white
pelican is found on freshwater wetlands with abundant reed beds and
grasses for nesting. In Africa the great white pelican is also found in
alkaline lakes
Breeding
The breeding season commences in April or May in temperate zones,
essentially all year around in Africa and begins in February through
April in India. Large numbers of these pelicans breed together in
colonies. The female can lay from 1 to 4 eggs in a clutch, with two
being the average.
Nest locations are variable. Some populations making stick nests in
trees but a majority, including all those who breed in Africa, nest
exclusively in scrapes on the ground lined with grass, sticks, feathers
and other material.
The young are cared for by both parents. The incubation stage lasts for
29 to 36 days. The chicks are naked when they hatch but quickly sprout
blackish-brown down. The colony gathers in "pods" around 20 to 25 days
after the eggs hatch. The young fledge at 65 to 75 days of age. Around
64% of young successful reach adulthood, with sexual maturity attained
at 3 to 4 years of age. White Pelicans are often protected from bird-eating raptors by virtue of their own great size, but eagles, especially sympatric Haliaeetus
species, may predate their eggs, nestlings and fledgings. Occasionally,
pelicans and their young are attacked at their colonies by mammalian carnivores from jackals to lions.
As is common in pelicans, the close approach of a large predaceous or
unknown mammal, including a human, at a colony will lead the pelican to
abandon their nest in self-preservation. Additionally, crocodiles, especially Nile crocodiles in Africa, will readily kill and eat swimming pelicans
Range
Sedentary populations are found year-round in Africa, south of the
Sahara Desert. Migratory populations are found from Eastern Europe to
Kazakstan during the breeding season and from northeast Africa through
Iraq to north India in the winter. Great white pelicans have also been
seen in southern Vietnam
Feeding Behaviour
The diet of the Great White Pelican consists mainly of fish.
The pelicans leave their roost to feed early in the mornings and may
fly over 100 km (62 mi) in search of food, as has been observed in Chad and Mogode, Cameroon. Each pelican needs from 0.9 to 1.4 kg (2.0 to 3.1 lb) of fish every day.
This corresponds to around 28,000,000 kg (62,000,000 lb) of fish
consumed every year at the largest colony of Great White Pelicans, on Tanzania's Lake Rukwa,
with almost 75000 birds. Fish targeted are usually fairly large ones,
in the 500–600 g (1.1–1.3 lb) weight range, and are taken based on
regional abundance. Common Carp are preferred in Europe, mullet are preferred in China and Aphanius dispar (a carp) are preferred in India. In Africa, often the commonest cichlids, including many species in the Haplochromis and Tilapia genera, seem to be preferred.
The pelican's pouch serves simply as a scoop. As the pelican pushes its
bill underwater, the lower bill bows out, creating a large pouch which
fills with water and fish. As the bird
lifts its head, the pouch contracts, forcing out the water but
retaining the fish. A group of 6 to 8 great white pelicans will gather
in a horseshoe formation in the water to feed together. They dip their
bills in unison, creating a circle of open pouches, ready to trap every
fish in the area. Most feeding is cooperative and done in groups,
especially in shallow waters where fish schools can be corraled easily,
though these pelicans may forage alone as well.
Pelicans are not restricted to fish, however, and are often
opportunistic foragers. In some situations they eat chicks of other
birds, such as the well documented case off the southwest coast of South
Africa. Here breeding Pelicans from the Dassen Island colony predate chicks weighing up to 2 kg (4.4 lb) from the Cape Gannet colony on Malgas Island. Similarly, in Walvis Bay, Namibia the eggs and chicks of Cape Cormorants
are fed regularly to young pelicans. The local pelican population is so
reliant on the cormorants, that when the cormorant species experienced a
population decline, the numbers of pelicans appeared to decline as
well. Great White Pelicans also eat crustaceans, tadpoles and even turtles. They readily accept handouts from humans, and a number of unusual items have been recorded in their diet. During periods of starvation, pelicans also eat seagulls and ducklings. The gulls are held under water and drowned before being eaten headfirst. Pelicans will also rob other birds of their prey.
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