Rivaling the trumpeter swan is the American white pelican with a similar overall length. They are both very large and plump. This particular pelican has an overall length of roughly 50 to 70 inches which includes their beak that measures 11 to 14 inches. It also has the second largest average wingspan of any North American bird, after the California condor.
Their plumage is almost entirely bright white, except the black primary and secondary remiges. In flight, they are hardly visible. While breeding from early spring until after mid-late summer, the breast feathers have a yellowish hue. After molting into the eclipse plumage, the upper head often has a gray hue, as blackish feathers grow between the small wispy white crest. In the wild, they may live for over 16 years, but in captivity, the lifespan is over 34 years.
The only way to describe the bill is huge. It’s flat on the top with a large throat sac below. During the breeding season, it is vivid orange in color along with the iris, bare skin around their eyes and feet. The upper bill will have a flattened horn located about one-third of the bills’ length behind the tip also during the breeding season. After the birds have mated and laid their eggs, the horn is shed. Once the breeding season is over, the bare parts become duller in color, with the naked facial skin yellow and the bill, pouch, and feet an orangy-flesh color.
As far as the difference between males and females, this isn’t any. They look exactly alike. Young birds have light gray plumage with darker brownish nape and remiges, and their bare parts are a dull gray. When the chicks are born, they are naked at first and later grow white down feathers all over before molting to the immature plumage.
The American white pelican does not dive for its food, unlike the brown pelican. They catch their prey while swimming. A bird will eat more than four pounds of food a day. The diet consists of the common carp, shiners, Sacramento perch, yellow perch, rainbow trout, catfish and jackfish. They will also eat crayfish, amphibians, and at times salamanders. If they are nesting on saline lakes, and the food source is scarce, they will travel a great distance to find better feeding grounds.
American white pelicans come together in groups of a dozen or more birds to feed. This enables them to corral fish to one another. If they are in deep water, where fish can escape by diving out of reach, they prefer to forage alone. A practice known as kleptoparasitism is when one bird steals food from another bird, which this bird is known for. An American white pelican once tried to steal a fish from a great blue heron while both birds were in flight.
The American white pelican is protected by the Migratory Bird Treaty Act of 1918. Nesting failure is due to habitat loss, with flooding and drought being recurrent problems. With regards to human-related loss, this includes fishing gear, boating disturbance, and poaching. During the mid-20thcentury, there was a pronounced decline in the American white pelican numbers, with the main cause being the spraying of DDT, endrin and other organochlorides. But with stricter environmental protection laws, they are now stable and slightly increasing.