• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.682-687
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• 2018

This study investigated the food value of Paracyclopina nana for flounder Paralichthys olivaceus larvae in two feeding stages, rotifer (for 12 days) and Artemia (for 16 days). In the rotifer feeding stage, survival and growth of flounder larvae in the only P. nana (nauplii) feeding experiment were higher than in the only rotifer feeding experiment on 12 DAH (days after hatching). In the Artemia feeding stage, the growth of flounder larvae in the only P. nana (C4-adult) feeding experiment and mixture feeding experiment (P. nana+Artemia) were higher than in other experiments on 30 DAH, but the survival of flounder larvae did not differ significantly among experiments. The n-3 HUFA contents of nauplius and C4-adult were 4.0% and 5.4%, respectively. Overall the results of this study indicate that the brackish water cyclopoid copepod, P. nana, is an effective live food organism for larval seedling production of marine fish.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.367-373
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• 2005

We conducted a year-long survey in 2000 to examine seasonal fluctuations in the abundance of the demersal copepod Pseudodiaptomus sp., the dominant copepod in the Seomjin River estuary, where the spring tide strongly affects changes in salinity gradients. Pseudodiaptomus sp. was found throughout the year in the entire range of salinities measured, but most individuals appeared at oligohaline conditions below 5.0 psu, and less than $2\%$ were observed in polyhaline conditions above 18.0 psu. The peak abundance occurred during autumn in oligohaline waters, and the density was relatively low during the rainy season in summer. In spring and autumn, copepodites were most abundant in oligohaline waters, although they were also fairly abundant in mesohaline conditions $(5\~18\;psu)$. Females with egg sacs appeared in oligo- and mesohaline waters during spring and autumn but were seldom found in polyhaline conditions throughout the year. Our results indicate that, despite the strong physical influence of the tide, Pseudodiaptomus sp. can manipulate its position to remain at its preferred salinity. We also found that spawning mainly occurred in oligohaline waters twice a year.

• Korean Journal of Environmental Biology
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• v.19 no.2
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• pp.137-145
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• 2001

Although tidal current affects the distribution of zooplankton significantly, its impacts were usually ignored when the studios on the zooplankton abundance were conducted even in the Yellow Sea where tidal current was very strong. Furthermore, information on the tidal impacts was very limited in the Yellow Sea. In this study, the tidal current effects on the abundances of copepod genera Acartia, Calanopia, Calanus, Centropages, Corycaeus, Labidocera, Paracalanus, Tortanus in a fixed sampling station near the Sonanjido (Island) were studied. The abundance of copepods collected by the same sampling method nab highest when the tidal current was fastest at 2 or 3 hours after the high or low tide.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.50-56
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• 1988

In order to fine some proper bacterial food for Tigriopus japoncus, bacterial flora of the tide pool inhabited by the copepod has been isolated and tested as bacterial food. Food effect and optimum density of the bacteria in terms of survival rate of the copepod was measured in the larval and the adult stages. Among the 264 strains of isolated bacteria, Acinetobacter spp. Moraxella, spp., Flavobacterium spp. and Pseudomonas spp. were certified as effective food for the copepod. According to the experimental results, Acinetobacter spp. AG-3 was the most effective food for all the stages from nauplius to adult, while Moraxella spp. and Flavobacterium spp. were effective for copepodite stage, and Pseudomonas spp. for the adult stage only. The optimum density of bacteria for the food was about $10^6\;cell/ml$, which was the same average density of bacteria in the tide pool.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.66-69
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• 2000

The common harpacticoida copepod species Tigriopus japnnicus was often obseued in the mass culture of marine rotifer tanks of sea farming stations. In this study, we investigated the co-existing effect of T. iaponicus to the rotifer Brachionus rotundiformis population growth. The culture conditions as temperature, salinity, culture volume, photo period, culture period and observation interval were 25{\circ}C, 22ppt, 40ml, 12L:12D, 16 deys$ and every two days during the experimental period, respectively. Nannochloropsis oculata was used as the food for the two testing organisms. After counting the growth of rotifer and copepod, they were transferred to new culture tank with N. oculata at the density of $7{times}10^5\;cells/ml$. The population growth of B. rotundiformis was suppressed by T. japonicus when these two organisms were mix-cultured comparing to single culture of B. rotundiformis. But population growth of T, japomcus was not affected by the presence of B. rotundiformis. The interspecific relationships of prey-predation and food competition were not observed in the combination culture of rotifer B. rotundiformis and copepod T japonicus.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.369-379
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• 2010

Zooplankton community structure and copepod production in Seomjin River estuary were investigated at 10 stations along the salinity gradients from May 2009 to February 2010. Total zooplankton taxa were identified to be 31 in the study area and seasonal average abundance of zooplankton was $4,151\;ind.{\cdot}m^{-3}$ during the study period. Zooplankton community was mainly composed of coastal species in dry season. However, brackish species dominated in upper or middle part of this estuary in flood season. This study showed that the growth rates of Acartia spp. and Paracalanus parvus s.l. measured from field experiments were regulated by the variations of Hater temperature and salinity; The annual copepod production estimated by dominant copepod species was $3.49\;g\;C{\cdot}m^{-2}yr^{-1}$, and the relatively high production value could be explained by the high phytoplankton standing stocks and the mass occurrence of coastal and brackish species with relation to various salinity gradients in Seomjin River estuary.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.2
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• pp.129-139
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• 2008

Marine ecotoxicological standard method was applicated using marine rotifer and benthic copepod as primary consumer of marine ecosystem. Marine rotifer, Brachionus plicatilis and benthic copepod, Tigriopus japonicus were designated as standard test species with the endpoints of 24hr neonate mortality (24hr $LC_{50}$) and 48hr population growth (48hr $EC_{50}$) for rotifer, and 48hr nauplius mortality (48hr $LC_{50}$) for benthic copepod. Tests method was referred to those of ASTM (American Society for Testing and Materials) with the replacement of test species which are widely distributed in Korean waters. The two species showed a wide tolerance on salinity ($5{\sim}35\;psu$) and can be easily cultured in small space even they were not as sensitive as in the mortality test using the nauplius of marine invertebrates. However, these species revealed the significant "concentrationresponse relationship" tested with ocean disposal wastes, and reproducibility using cadmium as standard reference material between laboratories. Accordingly, these two species have good potential as test species for marine ecotoxicological test species. Also, we strongly recommend that at least one of these species be included in the test species of "battery test" in marine bioassay.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.95-96
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• 2003

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.290-291
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• 2002

• Korean Aquaculture
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• v.16 no.2
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• pp.4-11
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• 2004