Predation of Fishes on Open-ocean Species of Sea-skaters (Halobates spp.)

Abstract

Halobates specimens were found in the stomachs of six fish species, representing five families, collected by purse-seining flotsam in the tropical West Pacific. The insects occurred in the diets of 52 out of 85 trevally, Caranx sexfasciatus, but in only one of 130 individuals of seven other carangid species. The rudderfish, Kyphosus cinerascens, was also a significant predator of Halobates. Halobates eaten by trevally comprised almost exclusively H. micans and H. germanus, which agrees with the known distribution ranges of both species. A single male and female of H. sericeus were recorded from different trevally, caught at ca. lat. 4°N. These are the first records of H. sericeus from waters within lat. 10° of the Equator. Fishes, like sea birds, may be significant predators of open-ocean Halobates species.