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Vol. 47 No. 1, 2008
Monsoon-Driven Succession of Copepod Assemblages in Coastal
Waters of the Northeastern Taiwan Strait
Yang-Chi Lan1,2, Ming-An Lee1,3,*, Cheng-Hsin Liao1, Wen-Yu Chen1, Ding-An Lee2, Deng-Cheng Liu2, and Wei-Cheng Su2
1Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung 202, Taiwan
2Marine fishery division, Taiwan Fishery Research Institute, Keelung 202, Taiwan
3Remote Sensing Laboratory, Taiwan Ocean Research Institute, Taipei 100, Taiwan
Li-Chun
Tseng, Ram Kumar, Hans-Uwe Dahms, Qing-Chao Chen, and Jiang-Shiou Hwang
(2008) Weather conditions in our study area during the
northeasterly (NE) monsoon season are usually rough, and it is
difficult to sample on board a boat in winter; therefore, knowledge of
copepod assemblages is very limited. This study was carried out at the
beginning and end of the NE monsoon in Dec. 2003 and Feb. 2004,
respectively, in an attempt to understand variations in copepod
compositions. The Kuroshio water (KW) with high temperatures and
salinities flowed past our eastern stations and affected the
hydrographic conditions in these 2 study periods. At the same time, the
low-temperature and -salinity China coastal water (CCW) flowed
southward into our western stations in the early winter, while the
Kuroshio branch water (KBW) was also introduced in our study area, and
affected the hydrographic conditions of station D-2 in late winter. The
average chlorophyll-a
concentration was higher (37.0 mg/m2) in the late and lower
(14.8 mg/m2) in the early northeasterly monsoon. In the present study,
109 species of copepods belonging to 5 orders, 26 families, and 48
genera were identified. Copepod species diversity and evenness
increased in the CCW but decreased in the KW from early to late winter,
and were higher in the KW than in the CCW in our 2 study periods.
Indicator species of the CCW in early winter were Paracalanus aculeatus
(72.5%) and Euchaeta concinna (72.0%), which changed to Corycaeus (Ditrichocorycaeus) affinis (96.7%), Calanus sinicus (95.9%), P. parvus (94.6), and Acrocalanus gracilis (90.9%) in
late winter; those of the KW in early winter were Pleuromamma gracilis (100%), Calanopia minor (94.4%), Rhincalanus nasutus (92.3%), Temoropia mayumbaensis (90.7%), Calocalanus pavo (80.1%), Clausocalanus lividus (77.7%), Lucicutia flavicornis (73.4%), Acartia danae (72.6%), which were
replaced by Aetideus acutus
(100%), Copilia mirabilis
(100%), Farranula concinna
(96.5%) and Calanoides carinatus
(75.3%) in late winter.
Key words: Diversity,
Evenness, Kuroshio, China coastal water.
*Correspondence: Fax: 886-2-24634419. E-mail:
malee@mail.ntou.edu.tw
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