Vol. 43 No. 2, 2004

Spring Distribution of Copepods in Relation to Water Masses in the Northern Taiwan Strait

Yang-Chi Lan¹, Chang-tai Shih^2,3, Ming-An Lee^1,* and Hung-Zen Shieh¹

¹Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung, Taiwan 202
²Fisheries Research Institute, Keelung, Taiwan 202
³Canadian Museum of Nature, Ottawa 809, Canada

Yang-Chi Lan, Chang-Tai Shih, Ming-An Lee and Hung-Zen Shieh (2004) In this study, we investigated the spatial distribution of copepods and its relationship with water masses in the northern Taiwan Strait in May 2001. Based on the results of cluster analysis of species compositions of copepods collected, we could distinguish 3 copepod species composition groups, each associated with one of the 3 different water masses. The 1st group was associated with the Kuroshio Branch Current. It had high values for Shannon's species diversity and Simpson's species evenness indices. The dominant species in this group were Temora turbinata, Paracalanus parvus and Canthocalanus pauper. The 2nd group was associated with the China Coastal Current. It had low values for Shannon's diversity and Simpson's evenness indices, and its dominant species were P. parvus, Euchaeta sp., and Calanus sinicus. The 3rd group was found in the area receiving freshwater intrusion from the Tanshui River of Taiwan. It had the lowest values for Shannon's diversity and Simpson's evenness indices among the 3 groups. Its dominant species were T. turbinata, C. pauper, and Acrocalanus gibber.

Key words: Diversity, Evenness, Calanus sinicus, Kuroshio, China coastal current.

*Correspondence: Fax : 886-2-24634419. E-mail: malee@mail.ntou.edu.tw