4 days ago
The American white pelican rivals the trumpeter swan, with a similar overall length, as the longest bird native to North America. Both very large and plump, it has an overall length of 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. This large wingspan allows the bird to easily use soaring flight for migration. Body weight can range between 7.7 and 30 lb (3.5 and 13.6 kg), although typically these birds average between 11 and 20 lb (5.0 and 9.1 kg). One mean body mass of 15.4 lb (7.0 kg) was reported. Another study found mean weights to be somewhat lower than expected, with eleven males averaging 13.97 lb (6.34 kg) and six females averaging 10.95 lb (4.97 kg). Among standard measurements, the wing chord measures 20–26.7 in (51–68 cm) and the tarsus measures 3.9–5.4 in (9.9–13.7 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 are 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 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. (wikipedia)