Marine birds, Feedings behaviour, Interspecific relationships, Symbiosis, Fregatidae, Sulidae, Ilha dos Alcatrazes^i2^
Abstract
The frigatebird (Fregata magnificiens) often is referred to as a kleptoparasite of the brown booby (Sula lecogaster). This paper however, shows that the relationship between these species is more complex and that kleptoparasitism can be interpreted as just a part of a whole process of mutual exploration. When these birds fly behind fishing boats, F. magnificens locates the food source first and S. lecogaster then moves in and catches fish more efficiently in such a way that the frigatebird can no longer fish and has to fly away. When the fishing period is over then the frigatebird is thought to approach the brown boobies in order to get fish from them, as described in the literature, This leads to a revision on the interpretation about the relation between these species, from that of kleptoparasitism to this of mutual exploration.
