Vol. 50 No. 4, 2011

Effects of the Kuroshio Current on Copepod Assemblages in Taiwan

Shih Hui Hsiao^1,2,5, Tien-Hsi Fang², Chang-tai Shih^3,4, and Jiang-Shiou Hwang^5,*

¹Department of Science Education, National Taipei University of Education, Taipei 106, Taiwan
²Department of Marine Environmental Informatics, National Taiwan Ocean University, Keelung 202, Taiwan
³Institute of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung 202, Taiwan
⁴Canadian Museum of Nature, Ottawa K1P 6P4, Canada
⁵Institute of Marine Biology, National Taiwan Ocean University, Keelung 202, Taiwan

Shih Hui Hsiao, Tien-Hsi Fang, Chang-tai Shih, and Jiang-Shiou Hwang (2011) The Kuroshio Current (KC) is a northerly flowing warm-water current, which has major effects on the hydrography and faunal assemblages along the east coast of Taiwan. We studied the abundance and diversity of copepods at 5 stations for 3 consecutive years (2000-2002). Copepod samples were collected with a plankton net with a 1-m mouth opening and a mesh size of 333 μm deployed in oblique tows from 200 to 0 m in depth. In total, 174 copepod species including 6 orders, 31 families, and 68 genera (111 calanoids, 11 cyclopoids, 4 harpacticoids, 2 mormonilloids, 44 poecilostomatoids, and 2 siphonostomatoids) were identified at the species level. Spatial variations in copepod abundances among these 5 stations were not significant. The composition of the indicator species and cluster analysis varied seasonally, indicating seasonal succession. We suggest that copepod species of Acartia negligens, Clausocalanus mastigophorus, Cosmocalanus darwini, and Lucicutia flavicornis are indicator species of the KC in winter when the northeast monsoon (NEM) prevails; in contrast, Acrocalanus spp. and Canthocalanus pauper are indicator species in summer. Furthermore, Acr. cf. gracilis and Oncaea venusta served as indicator species on all investigated cruises. We thus concluded that the KC carries a wide range of warm-water copepods to the east coast of Taiwan and western Pacific Ocean year round. The NEM did not transport Calanus sinicus into the Kuroshio main current, indicating a boundary of the distribution of Cal. sinicus in the western Pacific Ocean.

Key words: Kuroshio Current, Copepod assemblages, Copepod distribution, Western Pacific Ocean, Indicator species.

*Correspondence: Fax: 886-2-24629464. E-mail:Jshwang@mail.ntou.edu.tw