Daily age and food habits of Lateolabrax latus larvae and juveniles occurring in the innermost shallow waters of Uwajima Bay, Japan

Abstract

Daily age and food habits of Lateolabrax latus larvae and juveniles were investigated at two different habitats in Uwajima Bay, western Shikoku, Japan. In the shallow zone at Miura, which contained eelgrass beds, larvae occurred from January and were collected abundantly in March. The size, age, and hatch-date distributions suggested that late-hatched specimens stay longer than early-hatched specimens at this station. On the contrary, in the intertidal flats of the Kunomura River mouth larvae were rarely collected, but juveniles were collected in relative abundance from April. The distributions in the intertidal flats station suggested that specimens had migrated from another location and then resided in the intertidal flats. Spatial and temporal trophic variations increased remarkably with metamorphosis, and thus, the spatial differences in growth rate were considered in relation to the trophic diversity of prey items. Our results suggest that the nursery environment, nursery utilization pattern, and food habits of early life stages of L. latus show remarkable flexibility. From the similarity of these ecological aspects with L. japonicus, which is a closely related species, we suggest the important role of the interspecific competition to the realized niche difference between Lateolabrax congeners. © 2006 Blackwell Science Asia Pty Ltd.