FISHERIES RESEARCH INSTITUTE,MOA,TAIWAN

The cold China Coastal Current flow from the East China Sea southward into the Taiwan Strait in winter and it is usually blocked by the warm Kruoshio Branch Current in the western water of Penghu. In February 2008, a China cold air mass intruded southeastward into the surrounding waters of Penghu unexpectedly. This cold accident caused a 3.5 ℃ drop in water temperature in the station A inner the Chingwan bay of Penghu in contrast to the same month of pervious year. There were 84 species of copepods and belonged to 2 orders, 23 families, and 38 genera in this study. The first five dominant copepods were Centropages tenuiremis, Paracalanus aculeatus, Oncaea venusta, Temora turbinata and Clausocalanus furcatus. The cluster analysis showed that copepod compositions at those stations inner the bay were significant differences with stations outside the bay. The Chignwan bay is a semi-closed bay and the rate of water change in the inner bay is slower than that in outer bay. The cold accident resulting from the intruding of China Coastal Current clearly changed the copepod compositions of Chingwan bay in the following two months.