• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.194-207
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• 1993

This paper deals with seasonal fluctuation of fish communities around the coast of Kunsan, Korea from 1992 to 1993. A total of 98 fish species with 82 genera, 47 families, and 14 orders were collected during the study. Among fishes caught by trawl net, Cynoglossus joyneri and Repomucenus ornatipinnis predominated throughout the year, and by long back net Harengula zunasi and Engraulis japonica except winter season. There is a difference between biomass caught by long back net and by trawl net, the former showing a peak in summer and the latter showing peaks in late spring and winter. This result appears to be due to the occurrences of Platycephalus indicus and Liparis tanakai for the spawning in investigated areas. Among the 14 species collected in the intertidal zone, 13 species of the family Gobiidae were mostly found in the spawning season. These results may suggest that the coastal area of Kunsan provides a good spawning ground for the coastal fishes. It is considered that the seasonal fluctuation of the abundance and species composition in fishes in this area is mainly affected by the water temperature and the bottom habitats.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.671-681
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• 2014

The distribution and abundance of coastal fish species in Asan Bay, Korea, were estimated from hydroacoustic survey and net catches. Acoustic data were collected with 38 and 200 kHz from July to October of 2012, and converted to the nautical area scattering coefficient (NASC, $m^2/mile^2$) for $0.25n{\cdot}mile$ along ten transects. Japanese anchovy Engraulis japonicus was the dominant specie in the net catches. The virtual echogram technique was used to distinguish E. japonicus from other species based on the differences in the mean volume backscattering strength (${\Delta}MVBS$) at 38 and 200 kHz. Engraulis japonicus and other fishes are mainly distributed in the center channel and outer part of Asan Bay. E. japonicus tends to move from inner to outer Asan Bay in summer and fall. From NASC data, the target strength and length-weight function of E. japonicus and other fishes were used to estimate the E. japonicus stock at 24.1-93.3 tons, and other fish at 40.6-88.4 tons from July to October 2012. The estimated anchovy biomass compared well with the cumulative catch weight from stow net catches. The hydroacoustic method offers an approach to understanding spatial/temporal structure and estimating the biomass of fish aggregations in coastal areas.

• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.11-23
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• 1998

A total of 64 fish species was collected by an otter trawl in the coastal water off Namhae Island from May 1989 to April 1990. The dominant species were Acentrogobius pflaumii, Chaeturichthys hexanema, Chaeturichthys sciistius, Thryssa kammalensis, and Repomucenus valenciennei which accounted for approximately 66.5% of the total numbers and 34.5% of biomass of fish collected. Fish collected in the study area were primarily small fish species or early juverniles of large fish species. Only about 15%, exceeded 10cm in standard length. Seasonal variations in both species composition and abundance of fishes were major characteristics in the study area. The peak abundance occurred in April and September, while the number of species was relatively high from October to January. However, both the number of species and abundance of fishes showed the lowest values in winter.

• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.35-40
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• 2012

The feeding habits of yellowback seabream, $Dentex$ $tumifrons$, were studied using 317 specimens collected in the coastal waters of Busan, from January to December, 2004. The size of the specimens ranged from 10.2 to 27.8 cm in standard length (SL). D. tumifrons had turned out a carnivore and opportunistic predator that consumed mainly shrimps. Fishes were next important prey items. Its diet also included anomurans, amphipods, crabs, echinodermata and cephalopods. Polychaetes, stomatopods, bivalves, ostracods, mysids and so on were minor preys. The individuals of smallest size class (10~13 cm SL) fed mainly on shrimps. In the next size class (13~16 cm SL), the proportion of shrimps decreased, whereas the consumption of anomurans, echinodermata and crabs increased. The proportion of these prey items decreased as body size increased, whereas the consumption of fishes gradually increased. Fishes accounted for almost stomach contents of larger individuals (more than 25 cm SL).

• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.20-26
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• 2012

The feeding habits of john dory, $Zeus$ $faber$, were studied using 462 specimens collected in the coastal waters of Geomun-do, Korea. The size of the specimens ranged from 7.8 to 40.2cm in standard length (SL). $Z.$ $faber$ was a piscivore that consumes mainly teleosts such as $Trichiurus$ $lepturus$, $Scomber$ $japonicus$, $Callanthias$ $japonicus$ and $Trachurus$ $japonicus$. Of the fish species $T.$ $lepturus$ was the most preferred prey. Its diet also includes cephalopods, shrimps and euphausia. Smaller individuals (<15 cm SL) fed mainly on fishes and cephalopods. The proportion of cephalopods decreased as body size increased, whereas the consumption of fishes gradually increased. Fishes accounted for almost stomach contents of larger individuals (more than 15 cm SL).

• Korean Journal of Ichthyology
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• v.27 no.3
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• pp.233-237
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• 2015

Fish assemblages in the coastal waters off Gampo in the East Sea of Korea were analyzed using the samples of fishes collected with pot nets June, September, and December 2005 and March 2006. During the study period, a total of 19 fish species representing 10 families in 4 orders were collected. The fish assemblages predominantly consisted of Conger myriaster, which accounted for 38.9% of the number of individuals and 52.2% in the biomass. The next major specimens were Takifugu niphobles, Sebastes schlegelii, Chaenogobius annularis, Hexagrammos agrammus and Hexagrammos otakii. These five fishes accounted 44.1% of total number of individuals and 37.3% of total biomass. The number of fish species was the highest in March 2006 and the lowest in December 2005. The number of individuals and biomass were the highest in September in 2005 and the lowest in December in 2005.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.1
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• pp.39-47
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• 2008

The fluctuation in the abundance and species composition of fish was investigated using a fyke net with entrances on both sides in the coastal waters of Geumo-do, Yeosu, Chollanam-do, Korea, from May 2003 to April 2004. A total of 2,379 fishes (392.13 kg) were sampled and classified into 11 orders, 34 families, and 53 species. The dominant orders were Perciformes, Scorpaeniformes, and Pleuronectiformes, which accounted for 67.9% of the collected fishes. The dominant species was Acanthopagrus schlegelii (235 individuals, 19.00 kg), followed by Konosirus punctatus (182 individuals, 9.53 kg), and Apogon lineatus (161 individuals, 1.69 kg). The number of individuals and biomass were higher in spring and summer than in winter, and the monthly variation may be related to the water temperature. The diversity index was highest in September (H'=2.9) and lowest in December (H'=1.8). The evenness index was highest in August (J=0.9) and lowest in December (J=0.7). The dominance index was highest in December (D=0.7) and lowest in August (D=0.2). The economically important species in this area are Acanthopagrus schlegelii, Konosirus punctatus, Lateolabrax maculatus, Argyrosomus argentatus, Trichiurus lepturus, Lateolabrax japonicus, and Sebastes schlegelii.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.2
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• pp.114-127
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• 2024

A variation of fish assemblage in the coastal waters of Sagye-ri, southern Jeju Island was determined using samples collected by trammel net from 2012 to 2022. The total fish species caught by trammel net were identified 88 species, 46 families, 12 orders, and the number of appearance and biomass were 3,479 individuals and 883.6 kg. The annual variation of species was the highest in 2013 at 46 species and the lowest in 2021 at 30 species. The seasonal variation of species was higher in summer at 67 species and lower in winter, autumn at 47 species. The annual diversity index, evenness index, and richness index were appeared 2.42-3.00, 0.69-0.78 and 5.18-7.24 at each years. The dominance index appeared highest in 2013 and the lowest in 2018. Cluster analysis based on the number of individuals of fish was classified into two groups at the dissimilarity level of 57%, and results of SIMPROF analysis revealed significant differences in community structure among the two groups. The subtropical fishes were identified a total of 42 species (47.7%) and the number of species was higher in 2013 at 25 (54.3%) species and lower in 2018 and 2021 at each 17 (54.8~56.7%) species. The dominant species of subtropical fishes were appeared rabbit fish (Siganus fuscescens), scarbreast tuskfish (Choerodon azurio), bluestriped angelfish (Chaetodontoplus septentrionalis), balloon fish (Diodon holocanthus), and flag fish (Goniistius zonatus) at study sites.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.2
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• pp.319-344
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• 2015

A seasonal characteristic of marine environment and fish assemblages in the coastal waters of Jeju Island were determined using samples collected by a trammel net in from 2012 to 2013. Annual mean temperature and salinity were $18.8^{\circ}C$, 33.7psu (2012) and $18.8^{\circ}C$, 33.8psu (2013) which shows stable water mass. nutrient concentrations represent that dissolved inorganic nitrogen (DIN) ranged from 0.030 to 0.217mg/L, dissolved inorganic phosphorus (DIP) from 0.002 to 0.010mg/L, and silicate ($SiO_2$) from 0.096 to 0.292mg/L. Chlorophyll a concentrations of phytoplankton ranged from 0.905 to $1.125{\mu}g/L$ were appeared the highest in summer and the lowest in winter. Suspended Solid(SS) concentrations ranged from 1.200 to 2.100mg/L (mean, 1.634mg/L) were appeared the highest in autumn and the lowest in spring. During the survey period, a total of 83 species (48 families and 12 orders) of fishes were identified, Perciformes and Scorpaeniformes accounted for 63.9% of the total number. The number of species was higher in summer than in winter, showing a peak in summer at 57 species and a low in winter at 47 species. The number of individuals and the biomass peaked in summer at 694 individuals and 151.9kg, and were the lowest in autumn at 466 individuals and 106.5kg. The diversity index, evenness index and richness index were appeared 2.92~3.14, 0.75~0.83 and 7.06~8.56 at each stations. the dominance index were appeared highest in spring and summer, were appeared the lowest in winter and autumn. The Filefish (Stephanolepis cirrhifer), Bluestriped angelfish (Chaetodontoplus septentrionalis), Marbled rockfish (Sebastiscus marmoratus), Rabbit fish (Siganus fuscescens), Blackfin sweeper (Pempheris japonica) were dominant species, which occurred abundantly during the entire survey period. The subtropical fishes were identified total of 41 species (49.4%) and the number of species was higher in summer at 29 (50.9%) species and a low in winter at 20 (42.6%) species. The dominant species of subtropical fishes were appeared Bluestriped angelfish, Blackfin sweeper, Rabbit fish, Scarbreast tuskfish (Choerodon azurio), Ballonfish (Diodon holocanthus), Flagfish (Goniistius zonatus), Blue-spotted boxfish (Ostracion immaculatus) in study sites. The subtropical fishes of species, individual and biomass showed significant correlation with environmental factors (Chlorophyll a, DIN, DIP, $SiO_2$) in almost all sampling sites.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.164-179
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• 2001

Spatio-temporal variation in species composition, abundance and distribution of fisheries resources caught by large purse seine off Korea from 1991 to 1994 was analysed. Out of 19 species, Scomber japonicus (54.7%), Sardinops melanostictus (20.4%), Trachurus japonicus (9.1%), and Scomberomorus niphonius (6.2%) were predominated in catch. These 4 pelagic fishes occupied 90% of total catch. Major pelagic fishes caught by large purse seine were dispersed to northward from spring to summer, and migrated to the southern wintering ground during winter. Fishing effort (number of haul) was high in summer, but catch per unit effort showed a peak in winter. The high CPUE in winter seemed to be related to aggregation of the pelagic fish to the wintering ground in the southern sea. After spawning, they were widely dispersed for feeding in warm months.