Feeding habits of juvenile Parrotfish, Oplegnathus fasciatus (Temminck and Schlegel, 1844) , in the coastal waters of Gijang, Korea

The juvenile Oplegnathus fasciatus were collected off the Gijang, Korea coast. A total of 203 juvenile O. fasciatus were examined , the range of total length (TL) was 7.9-31.0 mm. The most important prey component of O. fasciatus was Copepods, with 75.0% in IRI (index of relative importance) index. Among Copepods, Paracalanus parvus s.l. in the Calanoida was the most significant dietary component. Cladocera was the second important prey component. Pisces, Amphipoda, Decapoda, , the other preys accounted for less than 1.8% of the diet by IRI index. The feeding strategy showed that O. fasciatus held a specialist niche with a considerable individual specialization. The result of analysis in ontogenetic changes was significantly exhibited among size classes. The proportion of Copepods decreased as increasing in body size, whereas the consumption of Cladocera, Pisces, Amphipoda, and Decapoda increased gradually. As body size increased, both the mean numbers of prey per gut (mN/Gut) and the mean volume of prey per gut (mV/Gut) constantly increased.