Large and primarily white, the American white pelican has the longest wingspan of any bird in Oregon. It also has an enormous orange bill, and flies with neck withdrawn.
During the breeding season the top of the bird's head becomes dusted with black and a horn grows on the upper mandible; this projection serves as a target for aggressive encounters to avoid injury to the essential bill pouch, but is shed after the eggs are laid.
This pelican makes unusually long flights for feeding and migration, and at great distances, soaring flocks have been reported as UFOs.
In Oregon, it breeds at a few interior sites with differing regularity, including Malheur, Lower Klamath, and Upper Klamath National Wildlife Refuges; Summer Lake Wildlife Area; Warner Basin; and islands in the Columbia River east of Arlington. It is locally common to abundant March through October in Klamath, Lake and Harney counties. Other eastern locations in spring and summer (non-breeding sites) include near Prineville, Crook County; Hermiston, Umatilla County; La Grande, Union County; Richland, Baker County and Vale and Jordan Valley, Malheur County. Postbreeding, this species may occur anywhere in eastern Oregon, particularly at Malheur Lake and reservoirs east of the Cascades.