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Gregory R. Mann, Ph.D. {ret.}

Australian Pelican

“Pelecanus conspicillatus”

The Australian Pelican’s bill is 40 centimeters to 50 centimeters long and is larger in males than in females and have large wings with a wingspan of 2.3 meters to 2.5 meters. The Australian Pelican is found throughout Australia, Papua New Guinea and western Indonesia, with occasional reports in New Zealand and various western Pacific islands. Australian Pelicans are widespread on freshwater, estuarine & marine wetlands and waterways including lakes, swamps, rivers, coastal islands and shores. The name “pelican” comes from the Ancient Greek word pelekan (πελεκάν), which is itself derived from the word pelekys (πέλεκυς) meaning “axe”. Australian Pelicans are highly mobile, searching out suitable areas of water and an adequate supply of food. They are not capable of sustained flapping flight, but can remain in the air for 24 hours, covering hundreds of kilometers. They are excellent soarers and can use thermals to rise to considerable altitudes. Flight at 1,000 meters is common and heights of 3,000 meters have been recorded. By moving from one thermal to the next, Australian Pelicans can travel long distances with a minimum of effort, reaching air speeds of up to 56 kilometers per hour. The bill and pouch of the Australian Pelican 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, probably for gripping slippery food items. When food is caught, the Australian Pelican manipulates it in its bill until the prey typically has its head pointing down the throat. Then with a jerk of the head, the Australian Pelican swallows the prey. The bill is delicately built with the lower jaw consisting of 2 thin & weakly articulated bones from which the pouch hangs. When fully extended, the bill can hold up to 13 liters. The pouch does not function as a place to hold food for any length of time, instead it serves as a short-term collecting organ. Australian Pelicans like all 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 maneuver 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 Australian Pelicans drinking by opening their bill to collect rainwater. The Australian Pelican may feed alone, but more often feeds as a cooperative group. Sometimes these groups are quite large. One group in 2015, numbered over 1,900 birds. A flock 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.

Breeding depends on environmental conditions, particularly rainfall. Australian Pelicans are colonial breeders with up to 40,000 individuals grouping on islands or secluded shores. Breeding begins with courtship. The female leads potential mates (2 to 8 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 color 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 color 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 3 days, egg-laying begins and eggs are laid 2 to 3 days apart. Both parents share incubation and the eggs are incubated on their feet. 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 Australian 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 color of the eyes varies from white to dark brown. This individual variation helps the parents to recognize their chick from hundreds of others. The Australian Pelican chicks leave their nests to form creches of up to 100 birds. They remain in creches for about 2 months, by the end of which they have learn to fly and are fairly independent and may live between 10 to possibly 25 years or more.

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