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 Pelicans: Amazing Facts and Photos

Introduction Information

Unique among the world's seven species of pelicans, the Brown Pelican is found along the ocean shores and on only a few inland lakes in the southwestern U.S. It is the only dark pelican, and also the only one that plunges from the air into the water to catch its food. They may live between ten and possibly 25 years or more.
What do they look like?
Males are larger than females. The stand out feature is the elongated bill with its massive throat pouch. The bill is 40 - 50 cm long and is larger in males than females. Pelicans weigh 4.0 - 6.8 kg and are 1.6 - 1.8 m long. They have large wings and a wingspan of 2.3 - 2.5 m. They have an extremely light skeleton, weighing less than 10% of their total body weight.
Where do they live?
The Australian Pelican is found throughout Australia, Papua New Guinea and western Indonesia, with occasional reports in New Zealand and various western Pacific islands. In Australia it is widespread on freshwater, estuarine and marine wetlands and waterways including lakes, swamps, rivers, coastal islands and shores.
What do they eat and how?
Pelicans mainly eat fish, but they are opportunistic feeders and will 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 have been reported capturing and eating seagulls and ducklings. The gulls are held under water and drowned before being eaten headfirst. Pelicans will also rob other birds of their prey.
The bill and pouch of pelicans play an important role in feeding. The bill is sensitive and this helps locate fish in murky water. It also has a hook at the end of the upper mandible for gripping slippery food items. When food is caught, the pelican manipulates it in its bill until the prey has its head pointing down the pelican's throat. Then with a jerk of the head the pelican swallows the prey. The pouch serves as a short-term collecting organ. Pelicans plunge their bills into the water, using their pouches as nets. Once something is caught, a pelican draws its pouch to its breast. This empties the water and allows the bird to manoeuvre the prey into a swallowing position. The pouch can also serve as a net to catch food thrown by humans, and there are sightings of pelicans drinking by opening their bill to collect rainwater.  When fully extended, the bill can hold up to 13 litres.
Behaviour
Australian Pelicans often feed as a cooperative group known as pods, scoops or squadrons.
Sometimes these groups are quite large. One group numbered over 1,900 birds. A pod of pelicans works together, driving fish into a concentrated mass using their bills and sometimes by beating their wings. The fish are herded into shallow water or surrounded in ever decreasing circles.
Pelicans are highly mobile, searching out suitable areas of water and an adequate supply of food. Pelicans are not capable of sustained flapping flight, but can remain in the air for 24 hours, covering hundreds of kilometres. They are excellent soarers and can use thermals to rise to considerable altitudes. Flight at 1,000m is common, and heights of 3 000 m have been recorded. By moving from one thermal to the next, pelicans can travel long distances with a minimum of effort, reaching air speeds of up to 56 km/hour.
Breeding and Raising their Young
Pelicans are colonial breeders with up to 40 000 individuals grouping on islands or secluded shores. Breeding may occur at any time of year depending on environmental conditions, particularly rainfall
Breeding begins with courtship. The female leads potential mates (two to eight or more) around the colony. As the males follow her in these walks, they threaten each other while swinging their open bills from side to side trying to attract the female's attention. The males may also pick up small objects, like sticks or dry fish, which they toss in the air and catch again, repeating the sequence several times.
Both sexes perform "pouch-rippling" in which they clap their bills shut several times a second and the pouch ripples like a flag in a strong breeze. As the courtship parade progresses, the males drop out one by one. Finally, after pursuits on land, water or in the air, only a single male is left. The female leads him to a potential nest site.
During the courtship period, the bill and pouch of the birds change colour dramatically. The forward half of the pouch becomes bright salmon pink, while the skin of the pouch in the throat region turns chrome yellow. Parts of the top and base of the bill change to cobalt blue, and a black diagonal strip appears from the base to the tip. This colour change is of short duration, the intensity usually subsiding by the time incubation starts.
The nest consists of a scrape in the ground prepared by the female. She digs the scrape with her bill and feet, and lines it with any scraps of vegetation or feathers within reach of the nest. Within three days egg-laying begins and between one and three eggs are laid two to three days apart. The eggs are incubated on the parents' feet.
Both parents share incubation which lasts between 32 and 35 days. Pelican chicks communicate with their mothers while still in the egg.  They can communicate as to whether they are too hot or cold.
They also listen to their parents from the egg - so when they emerge, they have no trouble identifying their parents.
The first-hatched chick is substantially larger than its siblings. It receives most of the food and may even attack and kill its nest mates. A newly hatched pelican has a large bill, bulging eyes and skin that looks like small-grained bubble plastic. The skin around the face is mottled with varying degrees of black and the colour of the eyes varies from white to dark brown. This individual variation helps the parents to recognise their chick from hundreds of others.
After about a month the chicks leave their nests to form creches of up to 100 birds. They remain in creches for about two months, by the end of which they have learnt to fly and are fairly independent. 


 

 

 

 

 


 
source: dolphins.com.au,ibda3world.com
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