Unlike the brown pelican, the great white pelican feeds from the surface. Birds form a line or a horseshoe on shallow water, advance together, and drive fish ahead of them into water shallow enough to catch. At the right moment the group dips its bills, each pouch scooping water and fish together.
The pouch then works as a strainer. A pelican tips its bill down, lets several litres of water drain from the sides, and swallows what remains. Handling takes several seconds, during which gulls and other birds regularly try to snatch the catch straight from the pouch. The bill and pouch are large, and in this species the bill is among the longest of any bird.
The persistent misconception is that a pelican carries fish around in its pouch as though it were a bag. It does not: the catch is swallowed within seconds and, for chicks, regurgitated at the nest. What varies and is not fully explained is why some colonies fish cooperatively in tight formation while nearby individuals feed alone.