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Vol. 47 No. 2, 2008
The Coupling of Copepod Assemblages and Hydrography in a Eutrophic Lagoon in Taiwan: Seasonal and Spatial Variations
Pei-Kai Hsu1, Wen-Tseng Lo1,*, and Chang-tai Shih1,2,3
1Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
2Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung 202, Taiwan
3Canadian Museum of Nature, Ottawa, K1P 6P4, Canada
Pei-Kai Hsu, Wen-Tseng Lo, and Chang-tai Shih (2008) Seasonal
and spatial variations in the species composition and abundances of
copepods in relation to hydrographic conditions in Tapong Bay, a
tropical eutrophic lagoon in southwestern Taiwan, were investigated
bimonthly in 2003. The water temperature, salinity, and
chlorophyll a (Chl a) of the bay showed apparent seasonal changes, with cold, saline, low-Chl a water in the dry winter (Dec. and Feb.) in contrast to warm, fresh, and high-Chl a
water in the rainy summer (June and Aug.). In all, 84 copepod
species belonging to 15 families and 23 genera were identified. Parvocalanus crassirostris, Bestiolina amoyensis, Oithona oculata, Acartia sinjiensis, Acartia sp., and Temora turbinata
were predominant, and together they comprised 86.4% of the total number
of copepods. Although copepod parameters showed no significant
quantitative differences among seasons or sites, they showed apparent
variations and succession in some months and at some stations, implying
that different species may dominate different regions with different
seasonal distribution patterns. These variations in copepod
assemblages can also be seen from results of a principal component
analysis of station groups and cluster analysis of species
groups. The copepod assemblage showed larger variations in winter
and in the inner bay than in other seasons and regions, and each
station group displayed a distinctive distribution pattern. Our
results suggest that even though removal of oyster culture racks in
2002 resulted in an apparent increase in zooplankton number, multiple
environmental variables, such as food sources, wastewater discharges,
tidal flushing, and climate, are still interactively influencing the
distribution patterns of copepods as they were previously shown to be
doing in the bay.
Key words: Copepods, Distribution, Human impact, Lagoon.
*Correspondence: E-mail:lowen@mail.nsysu.edu.tw
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