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.
Reproduction
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.
Endangerment
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.
Classification:
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Aves
Order: Pelicaniformes
Suborder: Pelecani
Family: Pelecanidae
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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