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GUANO PRODUCERS of the Bird Islands of Peru are chiefly guanayes, piqueros 

 and alcatraces. Perhaps they are better known, respectively, as cormorants, 

 boobies and pelicans. On the opposite page are baby and half-grown pelicans, 

 Pelecanus thagus. Above an adult piquero, Sula variegata, is feeding her 

 downy nestlings. The process, as with most birds, is that of regurgitation. 

 Hungry young birds usually thrust their beaks down the throats of parent birds 

 and help themselves. The piquero is a species of booby bird having variegated 

 plumage. Below is a close-up of three downy stage nestlings. 



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