ဇင်မံင်

ဇင်မံင် (Pelicans) (ဗမာ ဌက်ကြီးဝံပို) ဝွံ ဒှ်ဂကူဂစေံဍာ် ဇၞော်ဇၞော် နွံဂၠိုင်ကဵု ဂကူ မလုပ်လၟိဟ် တၞောဝ်ဗဳဇ Pelecanidae ရ။ ဂစေံဇင်မံင် ဂှ် နွံကဵု ခၟူဂၠိင်င် ထိုင်ပါင်ဇၞော်ဇၞော် သွက်ဂွံ ဗက်ရပ်စက၊ ဂိုင်ဍာ် ကိုပ်ကၠာ ဟွံဂွံၚိတ်ဖျေဟ်ရ။

Pelican Temporal range: Early Oligocene-Recent, 28.1–0 Ma PreЄ Є O S D C P T J K Pg N
A great white pelican in breeding condition flying over Walvis Bay, Namibia.
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Pelecaniformes
Family:	Pelecanidae Rafinesque, 1815
Genus:	Pelecanus Linnaeus, 1758
Type species
Pelecanus onocrotalus Linnaeus, 1758
Species
8, see text

P. crispus     P. philippensis       P. rufescens       P. conspicillatus       P. onocrotalus           P. occidentalis     P. thagus       P. erythrorhynchos

Evolutionary relationships among the extant species based on Kennedy et al. (2013).

Living species of Pelecanus
Common and binomial names	Image	Description	Range and status
American white pelican Pelecanus erythrorhynchos Gmelin, 1789		Length 1.3–1.8 မဳတာs (4.3–5.9 ft), wingspan 2.44–2.9 မဳတာs (8.0–9.5 ft), weight 5–9 kiloဂရာမ်s (11–20 lb). Plumage almost entirely white, except for black primary and secondary remiges only visible in flight.	Monotypic. Inland North America, wintering in Mexico. Status: Least Concern.
Brown pelican Pelecanus occidentalis Linnaeus, 1766		Length up to 1.4 မဳတာs (4.6 ft), wingspan 2–2.3 မဳတာs (6.6–7.5 ft), weight 3.6–4.5 kiloဂရာမ်s (7.9–9.9 lb). Smallest pelican; distinguished by brown plumage; feeds by plunge-diving.	Five subspecies. Coastal distribution ranging from North America and the Caribbean to northern South America and the Galapagos. Status: Least Concern.
Peruvian pelican Pelecanus thagus Molina, 1782		Length up to 1.52 မဳတာs (5.0 ft), wingspan 2.48 မဳတာs (8.1 ft), average weight 7 kiloဂရာမ်s (15 lb). Dark with a white stripe from the crown down the sides of the neck.	Monotypic. Pacific Coast of South America from Ecuador and Peru south through to southern Chile. Status: Near Threatened.
Great white pelican Pelecanus onocrotalus Linnaeus, 1758		Length 1.40–1.75 မဳတာs (4.6–5.7 ft), wingspan 2.45–2.95 မဳတာs (8.0–9.7 ft), weight 10–11 kiloဂရာမ်s (22–24 lb). Plumage white, with pink facial patch and legs.	Monotypic. Patchy distribution from eastern Mediterranean east to Indochina and Malay Peninsula, and south to South Africa. Status: Least Concern.
Australian pelican Pelecanus conspicillatus Temminck, 1824		Length 1.60–1.90 မဳတာs (5.2–6.2 ft), wingspan 2.5–3.4 မဳတာs (8.2–11.2 ft), weight 4–8.2 kiloဂရာမ်s (8.8–18.1 lb). Predominantly white with black along primaries and very large, pale pink bill.	Monotypic. Australia and New Guinea; vagrant to New Zealand, Solomons, Bismarck Archipelago, Fiji and Wallacea. Status: Least Concern.
Pink-backed pelican Pelecanus rufescens Gmelin, 1789		Length 1.25–1.32 မဳတာs (4.1–4.3 ft), wingspan 2.65–2.9 မဳတာs (8.7–9.5 ft), weight 3.9–7 kiloဂရာမ်s (8.6–15.4 lb). Grey and white plumage, occasionally pinkish on the back, with a yellow upper mandible and grey pouch.	Monotypic. Africa, Seychelles and southwestern Arabia; extinct in Madagascar. Status: Least Concern.
Dalmatian pelican Pelecanus crispus Bruch, 1832		Length 1.60–1.80 မဳတာs (5.2–5.9 ft), wingspan 2.70–3.20 မဳတာs (8.9–10.5 ft), weight 10–12 kiloဂရာမ်s (22–26 lb). Largest pelican; differs from great white pelican in having curly nape feathers, grey legs and greyish-white plumage.	Monotypic. South-eastern Europe to India and China. Status: Near Threatened.
Spot-billed pelican Pelecanus philippensis Gmelin, 1789		Length 1.27–1.52 မဳတာs (4.2–5.0 ft), wingspan 2.5 မဳတာs (8.2 ft), weight c. 5 kiloဂရာမ်s (11 lb). Mainly grey-white all over, with a grey hindneck crest in breeding season, pinkish rump and spotted bill pouch.	Monotypic. Southern Asia from southern Pakistan across India east to Indonesia; extinct in the Philippines and possibly eastern China. Status: Near Threatened.

A brown pelican opening mouth and inflating air sac to display tongue and some inner bill anatomy

American white pelican with knob which develops on bill before the breeding season

An adult brown pelican with a chick in a nest in Chesapeake Bay, Maryland, US: This species will nest on the ground when no suitable trees are available.

Australian pelican displaying the extent of its throat pouch (Lakes Entrance, Victoria).

Pelicans are very large birds with very long bills characterised by a downcurved hook at the end of the upper mandible, and the attachment of a huge gular pouch to the lower. The slender rami of the lower bill and the flexible tongue muscles form the pouch into a basket for catching fish, and sometimes rainwater, though not to hinder the swallowing of large fish, the tongue itself is tiny. They have a long neck and short stout legs with large, fully webbed feet. Although they are among the heaviest of flying birds, they are relatively light for their apparent bulk because of air pockets in the skeleton and beneath the skin, enabling them to float high in the water. The tail is short and square. The wings are long and broad, suitably shaped for soaring and gliding flight, and have the unusually large number of 30 to 35 secondary flight feathers.

Males are generally larger than females and have longer bills. The smallest species is the brown pelican, small individuals of which can be no more than 2.75 kiloဂရာမ်s (6.1 lb) and 1.06 မဳတာs (3.5 ft) long, with a wingspan of as little as 1.83 မဳတာs (6.0 ft). The largest is believed to be the Dalmatian, at up to 15 kiloဂရာမ်s (33 lb) and 1.83 မဳတာs (6.0 ft) in length, with a maximum wingspan of 3 မဳတာs (9.8 ft). The Australian pelican's bill may grow up to 0.5 မဳတာs (1.6 ft) long in large males, the longest of any bird.

Pelicans have mainly light-coloured plumage, the exceptions being the brown and Peruvian pelicans. The bills, pouches, and bare facial skin of all species become brighter before breeding season commences. The throat pouch of the Californian subspecies of the brown pelican turns bright red, and fades to yellow after the eggs are laid, while the throat pouch of the Peruvian pelican turns blue. The American white pelican grows a prominent knob on its bill that is shed once females have laid eggs. The plumage of immature pelicans is darker than that of adults. Newly hatched chicks are naked and pink, darkening to grey or black after 4 to 14 days, then developing a covering of white or grey down.

Air sacs

Anatomical dissections of two brown pelicans in 1939 showed that pelicans have a network of subcutaneous air sacs under their skin situated across the ventral surface including the throat, breast, and undersides of the wings, as well as having air sacs in their bones. The air sacs are connected to the airways of the respiratory system, and the pelican can keep its air sacs inflated by closing its glottis, but how air sacs are inflated is not clear. The air sacs serve to keep the pelican remarkably buoyant in the water and may also cushion the impact of the pelican's body on the water surface when they dive from flight into water to catch fish. Superficial air sacs may also help to round body contours (especially over the abdomen, where surface protuberances may be caused by viscera changing size and position) to enable the overlying feathers to form more effective heat insulation and also to enable feathers to be held in position for good aerodynamics.

Distribution and habitat

Modern pelicans are found on all continents except Antarctica. They primarily inhabit warm regions, although breeding ranges extend to latitudes of 45° South (Australian pelicans in Tasmania) and 60° North (American white pelicans in western Canada). Birds of inland and coastal waters, they are absent from polar regions, the deep ocean, oceanic islands (except the Galapagos), and inland South America, as well as from the eastern coast of South America from the mouth of the Amazon River southwards. Subfossil bones have been recovered from as far south as New Zealand's South Island, although their scarcity and isolated occurrence suggests that these remains may have merely been vagrants from Australia (much as is the case today).

Behaviour and ecology

Breeding and lifespan

 

Pelecanus occidentalis, Tortuga Bay, Island of Santa Cruz, Galápagos