| Remarks |
Occupies coastal areas (Ref. 356). Only pelican species to plunge dive for fish. Forms feeding flocks (Florida). Feeds on anchovies in southern California. New colony may form from roost (birds loafing in areas other than their nesting colony). Facultative kleptoparasitism, or food theft, by shallow-diving Band-tailed Gulls (Larus belcheri), and Laughing Gulls (Larus atricilla) that preferentially steal fish from adults; in turn, pelicans attack deeper-diving Peruvian Boobies (Sula variegata). Neck molts to brown prior to its move into its nesting colony where courtship and pair formation occurs. Exhibits communal pre-pairing; head-turning behavior during mate selection and courtship where male and female display ritually by turning their head and bill (its weapon) away from each other; pair forms at location where male advertises. May mate within hours of pairing, possibly with same mate from a previous season; first egg laid after 3-10 days. Surface-nesting species; tree-nesting. Atricial; typically lays 3 eggs that hatch asynchronously; where first hatchling is larger than siblings and will generally have monopoly over feeding; chicks thermoregulate by huddling; all 3 hatched young are raised by parent only on years when food is abundant. Chicks feed on regurgitated fish from its parents' gullets. Mortality rate of immature birds is 70% in the first 15 months. In Florida, after the breeding season, migrates both north and south from their breeding site, while those nesting farther north move to the south. Severe ENSO (El Niño) events affecting the Humboldt current caused regular collapse of huge populations (20 times in the last 100 years) due to great drop in food availability; 1982-1982 ENSO event in Peru and Ecuador caused a huge drop in population numbers (presumed to have died). Significant egg-shell thinning due to DDT pesticide exposure in the 1960s documented in southern California with notable population declines; and breeding populations disappeared widely from the southeastern US. Oil pollution cause reduction in hatchability, growth retardation, developmental defects and increased sublethal effects in chicks. Intense fishing pressures in feeding areas cause population declines due to breeding failure (Ref. 87784). |
