Abstract
Feeding ecology of the small angelfish Centropyge ferrugatus was studied at the coral reefs of Okinawa, Japan. This angelfish fed mainly on detritus and algae by nipping substrate within a small home range. In the breeding season, both sexes allocated usually about 60% of their time to foraging in the daylight hours, but females foraged more frequently than males. Centropyge ferrugatus frequently approached and followed similar-sized fishes of various species. Both sexes nipped more quickly and frequently in the association than in solitary foragings. Smaller individuals (females) more frequently associated with other fishes. Circumstantial evidence suggested a high predation pressure on the angelfish.We suggest that the association provides an antipredatory benefit to the angelfish, and enables the angelfish to devote more time to feeding because of less time required for the vigilance against predators.
