FORAGING BEHAVIOR OF THE AMERICAN WHITE PELICAN (PELECANUS-ERYTHRORHYNCOS) IN WESTERN NEVADA

The foraging behavior of American White Pelicans (Pelecanus erythrorhyncos Linn.) breeding at Pyramid Lake in western Nevada was examined between 1984 and 1986. Pelicans seen feeding at Pyramid Lake during February and early March pirated fish from Double Crested Cormorants (Phalacrocorax auritus). When feeding with conspecifics, pelicans usually engaged in some form of "cooperative herding," either driving fish into shallow water or surrounding them in more open areas. Members of groups of two to six birds caught significantly more fish than single birds or those in larger groups. Strike frequency initially increased with group size, reaching an upper asymptote at a flock size of four. Tests with decoys revealed that pelicans were attracted to areas by the presence of other pelicans.