The American White Pelican (Pelecanus erythrorhynchos) is a large aquatic bird from the order Pelecaniformes. It breeds in interior North America, moving south and to the coasts, as far as Central America, in winter.
Description
The American White Pelican rivals the Trumpeter Swan as the longest bird native to North America.
Both very large and plump, it has an overall length is about 50–70 in
(130–180 cm), courtesy of the huge beak which measures 11.3–15.2 in
(290–390 mm) in males and 10.3–14.2 in (260–360 mm) in females. It has a
wingspan of about 95–120 in (240–300 cm). The species also has the second largest average wingspan of any North American bird, after the California Condor. Body weight can range between 9.2 and 30 lb (4.2 and 14 kg),
although typically these birds average between 11 and 20 lb (5.0 and
9.1 kg). Among standard measurements, the wing chord measures 20–26.7 in
(51–68 cm) and the tarsus measures 3.9–5.4 in (9.9–14 cm) long. The plumage is almost entirely bright white, except the black primary and secondary remiges,
which are hardly visible except in flight. From early spring until
after breeding has finished in mid-late summer, the breast feathers have
a yellowish hue. After moulting into the eclipse plumage, the upper head often has a grey hue, as blackish feathers grow between the small wispy white crest.
The bill is huge and flat on the top, with a large throat sac below, and, in the breeding season, is vivid orange in color as is the iris, the bare skin around the eye, and the feet. In the breeding season, there is a laterally
flattened "horn" on the upper bill, located about one-third the bill's
length behind the tip. This is the only one of the eight species of
pelican to have a bill "horn". The horn is shed after the birds have
mated and laid their eggs. Outside of the breeding season the bare parts
become duller in color, with the naked facial skin yellow and the bill,
pouch, and feet an orangy-flesh color.
Apart from the difference in size, males and females look exactly
alike. Immature birds have light grey plumage with darker brownish nape
and remiges. Their bare parts are dull grey. Chicks are naked at first,
then grow white down feathers all over, before moulting to the immature plumage.
Fact
The
White Pelican does not dive for fish as the Brown Pelican does.
Instead, it dips its head underwater to scoop up fish. Several pelicans
may fish cooperatively, moving into a circle to concentrate fish, and
then dipping their heads under simultaneously to catch fish.
Length
50–65 in
127–165 cm
Wingspan
96.1–114.2 in
244–290 cm
Weight
158.7–317.5 oz
4500–9000 g
Other Names
Pelican (blanc) d¿Amerique (French)
Pelicano Norteamericano (Spanish)
Habitat
Breeds mainly on isolated islands in freshwater lakes, forages on inland
marshes, lakes, or rivers, favoring shallows. Islands used for breeding
are often 30 or more miles from foraging areas. During the nonbreeding
season, American White Pelicans favor shallow coastal bays, inlets, and
estuaries.
Food
The American White Pelican forages mainly on fish in shallow wetlands;
crayfish, tadpoles and salamanders are also eaten. Researchers have
found regurgitated fish hooks and lures in colonies, suggesting that
pelicans also take game fish that have been injured or slowed by
anglers.
Nesting
The nest is a shallow depression with a low rim that the bird forms
while it is sitting, by raking up gravel, soil, or nearby vegetation
with its bill. The nest bottom consists of the same material, and
vegetative insulation or lining within the nest is rare.
Nests in colonies on islands that aren’t subject to regular flooding.
The eggs are typically laid on bare gravel, sand, or soil with little
vegetation in the immediate area. In forested regions, the American
White Pelican sometimes will nest under either deciduous or coniferous
trees.
Behaviour
The American White Pelican is a graceful flier, either singly, in flight
formations, or soaring on thermals in flocks. They soar in different
portions of thermals for different distances: wandering flights in lower
portions of a thermal, commuting flights at middle heights, and
cross-country flights in the upper reaches of thermal columns. They are
skilled swimmers, but they do not plunge-dive for prey like their
coastal relatives the Brown Pelican. Instead they make shallow dives
from the surface of the water or just plunge their heads underwater.
They often hunt for food in groups in shallow water.
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