Why is brown pelican useful?

The brown pelican is about four feet in length. It has a brown and gray body and a white head with a light brown crown. Its neck is dark brown during breeding season. Young pelicans are all brown. The brown pelican has a very long gray bill with a large pouch of skin. Its pouch holds two or three times more than its stomach can hold -- close to three gallons of fish and water! Males and females look the same