A PRELIMINARY IDENTIFICATION ON EARLY STAGE OF OYSTER LARVAE SOURCE AND DISPERSAL: A FIELD AND NUMERICAL STUDY NEARBY ZHOUSHEI RIVER ESTUARY, TAIWAN

Abstract

Oyster (Crassostrea angulata) has long been an important species for economic aquaculture in Taiwan. This study was motivated by a recent and emerged problem that the traditional regions where oyster larvae (OL) were collected in the south part of Zhoushei river during the past decades have already changed. Figure 1 depicts our study region with three geophysical features: (1)the biggest industrial park (i.e. Mailiao Industrial Park, MIP) in Taiwan is located at the mouth of Zhoushei river, (2)multiple sandbars exist within shallow-water regions, and (3)a wide range of tidal flats where a well-mixed estuary has been confirmed. We speculate that those factors may give a mixed contribution to water quality, flow structure and biological process, thereby affecting dispersal and connectivity of OL. Unfortunately, a conclusive reason causing the mentioned problem is still unknown. The main goal of this study is to identify where the OL may come from, and what affects the dispersal ranges and recruitment areas during early stages. In this paper, we shall present field and numerical results for a preliminary identification on early stage of OL source and dispersal.