Brown Pelican

Brown Pelican (Pelecanus occidentalis)
Spanish name: Pelicano Pardo, Buchon, Alcatraz

Habitat
This large pelican is found on coastal waters, around offshore islands, and occasionally in some river mouths and estuaries.

Range
It is common along the Pacific coast from southern British Colombia to southern Chile, and on the Atlantic from North Carolina to northern Brazil. In Costa Rica it is abundant all year on the Pacific, particularly on the Golfo de Nicoya and Guanacaste coast. They are occasionally found on the Atlantic side as well.

National Parks
Santa Rosa Nacional Park, Corcovado National Park; also abundant in Isla Guayabo.

Physical Description/Interesting Biology
Large and graceful in flight, the characteristic profile of the Brown Pelican is an unmistakable favorite on both coasts. Flocks of these birds often fly in line or V-formation, flapping and gliding synchronously over the water. With long wings and necks, a large straight bill and an enormous gular pouch for swallowing fish, the pelican has a distinct profile, matching its distinct behavior. It is common along coastal waters, to see the Brown Pelican elegantly soaring and abruptly plunge-diving for fish from up to 10 m in the air. The Brown Pelican has air sacs in the chest to absorb the impact of the water, and uses its gular pouch to scoop fish that are near the surface. This bird may also take scraps from fishing areas and follow fishing boats for waste.

The Brown Pelican population suffered heavily from DDT in the 1960s and 1970s; their plight strongly influenced the ban on DDT in 1972. Chemicals like DDT contain chlorinated hydrocarbons that cause egg shells to be so thin that they break before the chicks hatch. This causes dramatic declines in population. Since the ban, the Brown Pelican populations in the United States have been recovering. It still important in Costa Rica to monitor their populations to make sure new chemicals and pesticides are not causing the same problem there as in the U.S.

Young Brown Pelicans take 3 to 5 years to develop the full adult plumage with black-brown feathers on the underside and silvery brown on the back and wings, with a white or yellow head. Adult plumage changes throughout the year in complex patterns with the breeding cycle.

This pelican builds its small platform nest out of sticks at the top of a shrub or tree; the female lays 2 to 3 eggs, and both sexes share in parenting duties. Like all birds in the pelican family, the chicks, squealing loudly and pig-like, put their head into the mouth of the parent to eat regurgitated food. The parents and chicks can become very hot sitting in the sun at the nest. To avoid overheating while watching over the nest, a parent stands with its back to the sun and spreads its wings; this shades the front of its body, where the throat and gular pouch are cooled by the air because the blood vessels are close to the surface of the skin. Scientists have seen nesting colonies with hundreds of pelicans perfectly aligned and moving synchronously according to the sun's movement. Once a parent's mate returns, the hot adult speeds directly to water and dives in.

Diet
This large diving bird eats different kinds of fish.

Height/Weight
An adult Brown Pelican weighs 2 to 5 kg and is 109 cm long. Males are heavier and have longer wings and bills.

Brief Taxonomy
Order: Pelecaniformes
Family: Pelecanidae

Sources
R. W. Schreiber and M. B. McCoy in Janzen, Daniel H. Costa Rican Natural History. Chicago: University of Chicago Press, 1983.
Skutch, Alexander F. and F. Gary Stiles. A Guide to the Birds of Costa Rica. Utica: Cornell University Press,1989.
Stiles, F. G. in: Janzen, Daniel H. Costa Rican Natural History. Chicago: University of Chicago Press, 1983.