When breeding, males and females grow a flat horn on the bill. It is the only one of the eight pelican species with one, and it falls off later.

Wings over Water · day 4 of 7
Both sexes grow a flat horn on the upper bill, which they later shed.
It has the second-largest average wingspan in North America, after the California condor.
It does not dive but catches prey while swimming, often herding fish in groups.
In one case it took a fish from a great blue heron while both were flying.
Young pelicans spend about a month in a pod, growing feathers and learning to fly.
More about the American White Pelican
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