Seasonal relationships between the copepod community and hydrographic conditions in the southern East China Sea

Abstract

We studied the relationship between seasonal variation of the copepod community and hydrographic conditions in the southern East China Sea (ECS). Hydrographic conditions in the southwestern ECS were influenced by the China Coastal Current (CCC) from late autumn to early spring and by the South China Sea Current (SCSC) during the rest of the year, and in the southeastern ECS by the Kuroshio Current (KC) year-round. We identified 141 species of copepods belonging to 54 genera and 27 families. Diversity and evenness of copepods were higher in waters influenced by the KC and the SCSC, and lower in waters with intrusion of the CCC. The CCC transported dominant copepods such as Paracalanus aculeatus, Paracalanus parvus, and Calanus sinicus into the southwestern ECS in late autumn and winter, whereas the SCSC carried Temora discaudata, Oncaea venusta, and P. aculeatus in spring, and Undinula vulgaris, T. discaudata, and P. aculeatus in summer. In the southeastern ECS, the KC brought in tropical copepods having clear seasonal variations throughout the year. We examined the relationships between indicator copepod species and currents and oceanographic conditions, using canonical correlation analysis. © 2007 International Council for the Exploration of the Sea. Published by Oxford Journals. All rights reserved.