• Korean Journal of Ichthyology
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• v.21 no.1
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• pp.23-27
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• 2009

The feeding habits of Lateolabrax japonicus were studied based on an examination of the stomach contents of 344 specimens collected monthly from January to December, 2005 in coastal waters off Dolsan-do, Yeosu. The standard length (SL) of specimens ranged in 8.7~52.8 cm. L. japonicus is a piscivore that consumes mainly teleosts such as Engraulis japonicus, Trachurus japonicus, and Acanthogobius flavimanus. Its diet also includes Macrura, Amphipoda, Cephalopoda, Polychaeta, Mysidacea, and Branchyura. Small individuals (<25 cm SL) consume mainly Amphipoda and Macrura. The proportion of these prey items decreases with increasing fish size, and this decrease paralleled the increased fish consumption.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.2
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• pp.94-108
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• 1993

In order to investigate the relation between the environmental properties and catch fluctuation of set net fishing ground located in the coastal waters of Yeosu, oceanographic observation and catches on the grounds were carried out from Jan. to Dec. in 1990 and 1992. The results obtained are summarized as follows; 1) Because of the surveyed area is a costal shallow water, the fishing ground was influenced largely by atmospheric phenomena such as air temperature. precipitation. etc. and so showed large variations in temperature and salinity yearly. The inner water flowed out mainly between Yeosu ad Namhe-do, and then through Kumo-do between Dolsan-do and Kumo-do. On the other hand, off shore water was supplied into the fishing ground from the vicinity of Sori-do and Yokchi-do. thus the fishing ground was occupied usually by various sources of water. 2) The water mass in the fishing ground were divided into the inner water(29.0～30.6$\textperthousand$) and the mixed water(31,7～32.2$\textperthousand$) and off shore water(32.3～32.8$\textperthousand$) accourding to the distribution of salinity from T-S diagram plotted all salinity data observed in 1990 and 1992. In summer the inner and mixing water which was formed by river flowed southerly and spread south-easterly in the vicinity of Kumo-do. The off shore water which supplied from the vicinity of Sori-do and Yokchi-do and inner water formed the thermal front and halo front in summer. 3) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel>Horse mackerel >Hair tail>Common mackerel> Sardine> Anchovy. The Catches of anchovy and sardine were high in April to May and those of hair tail and horse mackerel in July to September, but spanish mackerel were caught during the whole period of fishing. When inner water and mixing water appeared respectively and inner water and mixing water speared together in the set net fishing ground, the set net showed a high catch.

• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.256-266
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• 2010

The distribution characteristics of the eggs and larvae of anchovy Engraulis japonica, and environmental factors in the southern coastal waters of Korea were investigated from May to August 2009. Eggs and larvae were mainly distributed in the waters off Naro Island, Namhae Island and Saryang Island. High densities of eggs and larvae in temperatures of $19.0{\sim}24.0^{\circ}C$, salinites of 33.0~34.4 psu, DO of 6.05~8.13 mg/L and chlorophyll-a $1.2{\sim}2.3{\mu}g/L$ were observed. Water temperature in the coastal region was higher than that in the open sea, while salinity was lower. Evidence of sea water intrusion toward Sori Island and Maemul Island, and an inner-water intrusion from Yeoja Bay, Gamak Bay and Gwangyang Bay were observed. High densities of eggs in early developmental stage occurred in waters off Naro Island, Dolsan Island and Namhae Island, but high densities of eggs in a later developmental stage occurred in waters off Yokji Island and Maemul Island. During the survey period, the proportion of later developmental-stage eggs was higher in the eastern part of the study area.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.223-233
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• 2006

The annual and spatial changes in the species composition of catch off Yeosu were analyzed using the daily sales slip catch data by a set net in the inshore waters off Dolsan Islands in Yeosu from April to October 2001, off Yeon Islands of Yeosu from April to October 2002 and in the offshore waters off Dolsan Islands of Yeosu from April to December 2003, respectively. Scomberomorus niphonius, Seriola spp., Trichiurus lepturus, Engraulis japonicus, Sarda orientalis, Todarodes pacificus, Pampus echinogaster, Sardinella zunasi, Scomber japonicus, Lophius litulon and Loligo beka were dominant species in abundance, indicating that pelagic fish were mainly caught by a set net off Yeosu. S. zunasi, P. echinogaster, Platycephalus indicus and L. beka inhabited mainly in the inshore waters, and S. niphonius, Seriola spp., T. lepturus, P. echinogaster, T. pacificus, Takifugu porphyreus and Pagrus major resided mainly in the offshore waters as the pelagic resident species. E. japonicus was a representative dominant species moving between the inshore and the offshore waters seasonally. S. zunasi and E. japonicus occurred in the inshore waters, and E. japonicus, L. litulon and Seriola spp. begain to be caught in the deep offshore waters in spring. Total catch was high during the summer season by migration of the open sea species such as T. lepturus, S. niphonius, S. japonicus, Seriola spp., S. orientalis, P. echinogaster and T. pacificus. In fall, S. niphonius, E. japonicus, Sphyraena pinguis, Siganus fuscescens and Leiognathus nuchalis were dominant in the inshore waters, and S. niphonius, P. echinogaster, Hyporhamphus sajori, S. japonicus and T. lepturus continued to occur from summer in the offshore waters but total catch decreased, indicating the typical seasonal variation pattern of the temperate region. Most of catchable fishes by a set net were the pelagic species showing a significant temporal variation. Collection and analysis of daily catch data by large set nets can be used to determine seasonal variation in species composition of pelagic fish in a study area.