The Brown pelican has been described as a comically elegant bird. It has a big bill, sinuous neck, and large, dark body. Groups of them glide above surf along western and southern coasts, gracefully echoing the waves with their rise and fall. They plunge-dive from high up to feed, the force of impact serving to stun small fish, which they then scoop up. Today this species is fairly common—a good example of recovery from the pesticide pollution that once threatened them with extinction.
The Brown pelican occurs throughout the Pacific, Atlantic and Gulf Coasts the Americas. They live year round in Puerto Rico, the U.S. Virgin Islands, and along the southeastern coast, and migrate to winter in central California and spend summer on the mid-Atlantic and northwest coasts. It is a strictly marine and coastal bird but occasionally follows large rivers during storms. It avoids open sea and rarely occurs far offshore, usually frequenting shallow waters along coasts, as well as estuaries and bays. It breeds on the arid coasts of flat, bare, remote islands, or occasionally in mangroves. It can often be seen around fishing ports.
This species is very gregarious and lives throughout the year in flocks with both genders. They are diurnal but sometimes forage at night during a full moon. They sleep on land either while standing on both their feet, or resting on breast and belly, their head sideways on their shoulder with their beak tilted towards the side. This is the only pelican species that dives from on high as the main method of obtaining food. Their air sacs enable buoyancy for them in the water. They do not swim under water but plunge their head below the surface when catching prey. A Brown pelican is territorial with regard to its nesting area. Threat displays, often carried out when another pelican is too close to an individual’s nest involve head swaying, indicating readiness to interact, and bowing and a "hrraa-hrraa" sound. Young pelicans who approach a nest too closely are often killed.
Brown pelicans are serially monogamous, which means they mate with only one partner in a breeding season. The male chooses and defends his nest site prior to courtship. Ritual displays may include head swaying, and bowing and turning, while the pair utter a low “raaa”. Once courtship is over, both birds build the nest in a tree, on a cliff or on the ground. The breeding season is in spring in the parts of the range in the north, but all year round in the tropics. These pelicans breed in colonies, and sites are sometimes maintained for several years. 2-3 white chalky eggs are laid. Both parents share the incubation of 28-30 days and all nesting duties. Once hatched, chicks are fed by the regurgitation of liquid matter, a sort of “fish-soup”, and later, regurgitated fish. For nests on the ground, young fledge when they are 63 days old, and depend on their parents for a further two weeks. Birds in tree nests fledge at about 74-76 days old and are immediately independent. These pelicans are sexually mature at 3-4 years.
Brown pelicans do not have many natural enemies. Although nests on the ground are sometimes destroyed by flooding, hurricane or other natural disasters, people pose the biggest threat to pelicans. In the early 20th and late 19th centuries, pelicans’ feathers were sought after to adorn women’s clothing, especially hats. Today tourists and fishermen threaten them by disturbing their colonies, especially in Mexico.
According to the U.S. Fish and Wildlife Service resource, the total population size of the Brown pelican is estimated at 650,000 individuals. Included are 12,000 breeding pairs in the U.S. Gulf Coast in Louisiana and Texas and over 11,000 breeding pairs of the southern Californian subspecies, which includes nesting islands off Mexico. Overall, currently Brown pelicans are classified as Least Concern (LC) on the IUCN Red List and their numbers today are increasing.
Brown pelican may have influence on the fish population due to their diet.