Overview
American White Pelicans are gregarious birds, often associated with Double-crested Cormorants. Few can fail to be impressed by the sight of this spectacular species, one of the largest boreal birds, soaring overhead or feeding in synchronized groups. A flock of migrating American White Pelicans is a majestic sight-a long line of ponderous birds, flapping and coasting. Each bird seems to take its cue from the one in front of it, beginning to flap and starting a glide when its predecessor does. These birds ride rising air currents to great heights, where they soar slowly and gracefully in circles. These birds are more buoyant than Brown Pelicans and do not dive for their food. They cooperate to surround fish in shallow water, scooping them into their pouches. They take in both water and fish, and then hold their bills vertically to drain out the water before swallowing the food. This species is something of a conservation success story, with major population declines and range contractions before 1980 largely reversed.
Description
55-70″ (1.4-1.8 m). W. 8′ (2.4 m). A huge white bird with a long flat bill and black wing tips. In breeding season, has short yellowish crest on back of head and horny plate on upper mandible. Young birds duskier than adults.
Voice
Usually silent; grunts or croaks on nesting grounds.
Nesting
1-6 whitish eggs on a low mound of earth and debris on a marshy island; occasionally on rocky islands in desert lakes. Nests in colonies.
Habitat
The American White Pelican is dependent on wetlands for its survival, and the boreal forest provides plenty. It nests on islands in freshwater and saline lakes, foraging in shallow waters up to 50 kilometers (30 miles) or more away. It uses similar foraging sites during migration to its largely coastal wintering sites. Preferred winter habitats are shallow bays, inlets, and estuaries containing suitable prey and loafing sites; it also can be seen on man-made ponds and lagoons.
Range/Migration
American White Pelicans segregate well into two separate geographic groups. Populations breeding east of the Rocky Mountains migrate south and east, mostly along river valleys, to winter along the Gulf of Mexico. Populations west of the Rockies migrate over deserts and mountains to the Pacific coast. Migration occurs mainly during daylight in flocks sometimes numbering in the hundreds, often flying in the familiar V-formation and using thermals when available. Fall migration is protracted, with individuals lingering on southerly breeding grounds as late as December in mild winters. Northern Illinois is on the eastern edge of their migratory route, so it is always a treat to see them in one of our lakes, ponds, or rivers. Spring arrival on breeding grounds is as early as February in Nevada, March in Utah, and April in Illinois (Chain-O-Lakes), Wyoming and Manitoba, usually before lakes but after rivers have thawed, providing some foraging sites even if nest sites are inaccessible. Large numbers of migrating pelicans can be seen in fall at Horicon National Wildlife Refuge in Wisconsin; in spring at Deer Flat National Wildlife Refuge in Idaho; and in both seasons at Cheyenne Bottoms Wildlife Area in Kansas and Sand Lake National Wildlife Refuge in South Dakota.
Diet/Feeding Behavior
Like all pelicans, the American White Pelican is primarily a fish eater. Its usual prey species are small schooling fish, but it also eats some bottom feeders; within the preferred size range, it is non-selective, taking prey purely on the basis of availability. It also takes salamanders and crayfish opportunistically. The species often uses a characteristic group feeding strategy wherein a flock will form a circle or semi-circle and, using coordinated bill dipping and wing beating, drive prey toward shore where it is more easily caught. It also forages individually but with lower success; foraging behavior tends to shift toward cooperation when prey aggregations are located. It commonly forages at night during the breeding season, using tactile means of locating prey; daytime foraging is probably more visual. This species never plunge-dives like the Brown Pelican (Pelecanus occidentalis). Daily food intake of breeding adults may reach 40 percent of body mass. White Pelicans often steal prey from one another and from other species, especially diving birds in deeper waters.
