The Brown Pelican (Pelecanus occidentalis) is a familiar sight along the coasts of North and South America, instantly recognizable by its large bill and distinctive gular pouch. Unlike its close relatives, this coastal seabird is known for its head-first plunge-diving technique to capture prey near the surface of the ocean. This specialized feeding behavior dictates the types of prey it pursues and the habitats it freque nts. A typical adult requires a substantial amount of food, consuming up to four pounds of fish daily to sustain its energy needs. The bird’s diet focuses almost entirely on certain species of small, schooling fish that are easily accessible from the air.
Primary Food Sources
The majority of the Brown Pelican’s diet consists of small, non-commercial, schooling fish species found near the water’s surface. Primary examples include Atlantic and Gulf menhaden, which account for a significant portion of their food intake in some regions. The supply of anchovies and sardines is also a major factor in the pelican’s successful feeding and breeding, particularly for populations along the Pacific Coast.
Other commonly consumed species are “rough” fish like herring, silversides, pigfish, mullet, and various minnows. The preferred prey size generally falls between six and twelve inches long. These fish are often considered commercially unimportant to human fisheries, minimizing direct competition for resources. Their schooling behavior makes them an efficient food source, allowing the pelican to capture multiple individuals with a single dive.
Hunting Technique and Anatomy
The Brown Pelican is the only pelican species that primarily uses an aerial plunge-dive to acquire its food. Flying above the water, the pelican uses its keen eyesight to spot schools of fish near the surface. Once a target is sighted, the bird folds its wings back and descends in a steep, high-speed dive before impact.
The bird’s anatomy is adapted for this high-impact maneuver; air sacs beneath the skin act as cushions to absorb the shock of hitting the water. Upon striking the surface, the pelican’s lower jaw bows outward, and the large, flexible gular pouch expands like a scoop. This pouch can hold up to three gallons of water along with the captured fish. The pelican then surfaces, tilting its bill downward to drain the water before swallowing the fish whole.
Opportunistic and Seasonal Variations
While small fish are the staple, the Brown Pelican is an opportunistic carnivore, and its diet expands based on availability and local conditions. Invertebrates, such as prawns and other small crustaceans, are sometimes consumed when preferred fish are scarce. They may also occasionally consume amphibians, or the eggs and nestlings of other birds.
Geographic location and seasonal changes in water temperature shift the specific fish species available to pelicans. Pelicans also exhibit scavenging behavior, sometimes feeding on dead or decaying material. They may gather around fishing vessels to consume discarded bycatch or scraps, ensuring they maintain energy requirements even when primary food sources fluctuate.