Pelicans are large water birds that live on seacoasts
or inwarminland water habitats. There
are seven generally recognized species. The
coastal brown pelican lives from North Carolina
to the Gulf of Mexico and the Caribbean, and from
British Columbia to Chile, as well as the GalГЎpagos
Islands. The American white pelican inhabits
inland habitats in the western, central, and
southeastern United States, Mexico, and Canada.
The remaining species live in Australia, Europe,
Asia, and Africa.
Physical Characteristics of Pelicans
Pelicans rank among the largest of living birds, ranging in size from four to six feet in length, and weighing from four to sixteen pounds. The brown pelican is smallest, and the large eastern great white pelican has a wingspan of up to ten feet. They have short legs and broad, fully webbed feet, which act as powerful paddles in the water, and cause them to walk with an awkward waddle on land. The pelican is famous for its huge, featherless throat pouch that is attached to the lower mandible. The pouch stretches as it fills with water when the bird is fishing, and can hold nearly three gallons. The pouch also functions as an evaporative cooling mechanism. The pelican opens it mouth and flutters its pouch, which keeps air flowing over the moist surface. Plumage color varies among species and according to age. Pelicans can be predominantly white, black, brown, or gray, with markings on the head, wingtips, underfeathers, or tail. The legs and feet are orange, brown, or black, and the bill and pouch are reddish, orange, or black. During the breeding season, these body parts change color, and many pelicans develop a yellow patch on the chest, a distinctive crest, and a bright ring around the eyes. The American white pelican also grows a noticeable horny knob on its beak.
Feeding and Other Behaviors
Pelicans feed on many species of saltwater and freshwater fish, fromtiny anchovies to fish weighing over a pound. Small crayfish, salamanders, frogs, and snakes are also consumed. The pelican thrusts its head and neck underwater and uses its pouch as a dip net to scoop up its prey. It drains out the water, then tilts its head back and swallows the fish whole. Many pelicans are social fishers, swimming in a circle to close in on the school, then all thrusting and dipping at once. Brown pelicans are solitary feeders, utilizing a spectacular plunge dive from about twenty feet above the water, with neck outstretched and bill pointed down. They hit the water hard, stunning the fish and trapping them in the pouch. Air sacs beneath the pelican's skin cushion its dive and help it to surface quickly. Pelicans are graceful fliers. They take off against the wind, beating their wings and pumping their feet simultaneously, hopping until they are airborne. They fly at a relatively slow speed, with their necks retracted and their heavy bills tucked in and resting on the breast, and often glide on thermals to conserve energy. Pelicans regularly fly in flocks in aV-formation, flapping their wings in unison. They often travel a great distance in search of food. Pelicans sleep standing or sitting on their bellies, with the head twisted back and the beak tucked into its feathers. Self-care activities include muscle exercises such as body shaking, wing flapping, tail wagging, leg stretching, bill throwing, and yawning. Pelicans groom themselves by splash bathing, preening with their beaks, and by rubbing their heads over the body to distribute waterproofing oil to their feathers.
Pelicans are warm weather birds, migrating in large flocks to nest in huge colonies. During courtship, the male uses various behaviors such as bowing, stretching, and pouch displaying to attract a female. Both engage in nesting, the male often gathering sticks and bringing them to the female to incorporate into the nest. Nests are built on the ground or in trees. One to three eggs are laid, and take thirty days to hatch. The chicks are born featherless, and the parents brood them, protecting them from the elements until their feathers come in. Unless the food supply is abundant, only the strongest chick survives. Young chicks eat the parent's regurgitated food. Older chicks feed by sticking their heads in the parent's pouch and throat. By twelve weeks of age, the chicks can fly and begin to hunt for themselves. By one year they have their full plumage. They begin reproduction at three to four years of age.
Pesticides, oil spills, habitat destruction, entanglement in fishing lines, and human disturbance have affected pelican populations in various parts of the world. In 1970, the U.S. Fish and Wildlife Service listed the brown pelican as an endangered species due to the heavy usage of dichlorodiphenyl- trichloroethane (DDT) and endrin.When pelicans ate DDT-contaminated fish, they produced thin-shelled eggs that crushed during incubation. Endrin was toxic. Populations improved after the pesticides were banned, but the birds are still endangered. The spot-billed pelican of Asia and the Dalmatian pelican of Europe and China also face difficulties.
Genus and species: Pelecanus onocrotalus (eastern great white pelican), P. erythrorynchos (American white pelican), P. occidentalis (brown pelican), P. rufescens (pink-backed pelican), P. philippensis (spot-billed pelican), P. crispus (Dalmatian pelican), P. conspicillatus (Australian pelican)
Geographical location: North and South America, eastern Europe, Asia, Africa, Australia
Habitat: Coastal areas or inland lakes and rivers
Gestational period: Incubation lasts thirty days
Life span: Eight to twenty years
Special anatomy:Webbed feet; long, pointed bill with retractable throat pouch; air sacs under the skin; large wingspan
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