Migration ecology of juvenile temperate seabass Lateolabrax japonicus: a carbon stable-isotope approach
Abstract:The migration pattern of juvenile temperate seabass Lateolabrax japonicus in the stratified estuary of the Yura River was examined using carbon stable-isotope ratios (δ 13C). δ 13C values of mysids, which are the most important prey items for this species, were consistently enriched in the lower estuary and surf zone (LES), while depleted in the freshwater zone (FW). δ 13C values of juveniles in LES were enriched, while those in FW were depleted, consistent with the δ 13C difference in prey items. The results of δ 13C showed that many juveniles migrated upstream from April to June and most of them stayed in FW until at least July. Juveniles that stayed in FW and LES for a relatively longer period (> c. 20 days) showed higher condition factors than those that stayed in FW for a short period (several days). This indicates that residence in FW enabled juveniles to achieve as good a body condition as residence in LES.
Document Type: Regular Paper
Affiliations: 1: Kyoto University, Graduate School of Agriculture, Oiwake, Kitashirakawa, Sakyo, Kyoto 606-8502, Japan 2: Quebec-Ocean, Departement de Biologie, Universite Laval, Quebec (QC), G1V 0A6 Canada 3: Kyoto University, Field Science Education and Research Center, Nagahama, Maizuru 625-0086, Japan
Publication date: 2011-06-01