• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.498-507
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• 2021

Ichthyoplankton (fish eggs and larvae) were collected seasonally collected from 2017 to 2019 to clarify whether Dokdo serves as a fish spawning and/or nursery ground. Fish eggs were identified and classified into 16 species. The dominant fish egg species were Engraulis japonicus, Maurolicus japonicus, and Parajulis poecilepterus. Fish larvae were identified and classified into 15 species. The dominant fish larvae species were E. japonicus, M. japonicus, and Sebastes owstoni. A cluster analysis similarity percentages revealed two distinct groupings according to sample location (stations) with E. japonicus and M. japonicus as the main group influencers. E. japonicus was the dominant species off Dokdo. The species diversity and abundance peaked in summer. The diversity index, richness index, and evenness index fluctuated seasonally. There were no predominant species variations among the years. Sedentary species such as P. poecilepterus, Semicossyphus reticulatus, and Glyptocephalus stelleri occurred in the inshore stations. E. japonicus, M. japonicus, and Trachipterus trachypterus occurred in the offshore stations. Our results show these species use Dokdo as spawning and nursery grounds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.761-772
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• 2020

In order to study about species composition and community structure of fish in the coastal water off Boryeong were investigated from January 2018 to December 2019. A total of 10,863 individuals of 87 species of 44 families were collected. The dominant species were Liparis tanakai accounted for 19.8 percent of the total with Amblychaeturichthys hexanema and Collichthys niveatus accounted for 12.4 percent and 11.0 percent of the total number. A cluster analysis based on the Bray-Curtis similarity revealed that the fish community divided into two groups, According to season. The fish species that appeared summer and autumn were mainly migratory, while the fish species that appeared in spring and winter were mainly resident species. Fish caught by stow net had a high percentage of immature fish. It presented that coastal water off Boryeong is located an important spawning and nursery for fisheries resource.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.4
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• pp.378-388
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• 2003

Seasonal variations in abundance and species composition of fish assemblage around Narodo were examined. Fish samples were monthly collected by a beam trawl from December 2000 to November 2001. A total of 62 fish species representing 37 families were collected. Of these, Thryssa kammalensis, T. hamiltoni, Chaeturichthys hexanema, Johnius grypotus, Leiognathus nuchalis, Cynoglossus robustus and Setipinna taty were dominant species comprising $82\%$ of the total number of individuals. Species diversity indices ranged from 1.2 to 2.2 showing the highest values from September to November 2001. The fish assemblage was divided into three different groups by cluster analysis of the fourteen dominant species. The main residence species were J. grypotus, L. nuchalis, C. hexanema, C. robustus, Setipinna tenuifilis, T. kammalensis and Ctenotrypauchen microcephalus. Of the temporal species T. hamiltoni, Liparis tanakai and Erisphex pottii were collected In spring, and Muraenesox cinereus and Trichiurus lepturus were in summer and autumn. Principal component analysis revealed that seasonal variation in the fish assemblage was attributed to the abundance of temporal species due to seasonal variation of environmental factors such as water temperature and ecological pattern (polagic/demersal) of fish species.

• Korean Journal of Ichthyology
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• v.17 no.1
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• pp.8-18
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• 2005

A total of 33 fish species were collected by a small beam trawl from an eelgrass bed in Myoungjuri of Jindong Bay, Korea. The dominant fish species were Hexagrammos otakii, Pholis fangi, Repomucenus valenciennei, Pseudoblennus cottoides, Pholis nebulosa, Rudarius ercodes, Syngnathus schlegeli, and Sebastes schlegeli. These 8 fish species accounted for 79.5% of the total number of individuals collected. The fishes collected in the study area were primarily small fish species or juveniles of large fish species. Seasonal variations in both species composition and abundance were large; higher numbers of fish occurred from April to June 2002, while biomass was the highest in September 2001 and 2002. Seasonal changes in fish abundance corresponded with eelgrass biomass and abundance of food organisms.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.630-636
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• 2015

The study aims at analyzing a species composition of the fish live in bottom of the coastal waters off Sejon island, Korea. To reach the goal of the study, a species composition and it's seasonally fluctuation, a seasonally fluctuation of the dominant species and it's appearance type were analyzed with the fishes caught by the bottom trawl in the coastal waters off Sejon island from May, 2011 to March, 2012. The results obtained can be summarized as follows; Fish caught in this area composes 10 orders, 25 families, and 37 species. The most dominant species in an number of fish was Pennahia argentata which was occupied at 42.1% from the whole number, the second most dominant species was Konosirus punctatus which was occupied at 14.2%. The most dominant species in a biomass of fish was Pennahia argentata which was 31.3% out of the whole catch, the next dominant species was Lophius litulonwhich which was 18.2%. The first group (Trichiurus lepturus, Zeus faber, Pennahia argentata, Chelidonichthys spinosus and Lophius litulon) was appeared at May, August, October, the second group (Sphyraena pinguis) was appeared at May and November, the third group (Pampus argenteus) was appeared at August, the fourth group (Pampus echinogaster, Leiognathus nuchalis, Konosirus punctatus and Engraulis japonicus) was appeared at March.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.328-333
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• 2019

The proximate composition and mineral contents of 18 subtropical fish species caught off the coast of Jeju Island, Korea were determined. The mean moisture content was highest (78.0%) in the eight species of lean fish, lowest (72.6%) in the four species of medium-fat fish, and intermediate (75.4%) in the six species of low-fat fish. The lipid content was in the order of medium-fat fish > low-fat fish > lean fish. The protein content ranged from 17.7% to 18.9%. The mean macro-mineral contents in the 18 species were 290.2 mg/100 g edible portion K, 146.6 mg P, 113.5 mg Na, 67.2 mg Ca and 38.3 mg Mg. The mean value of micro-mineral contents were 2.1 mg Fe, 1.7 mg Cu and 1.5 mg Zn. These results suggest that subtropical fish from Jeju Island are good sources of protein, lipid and minerals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.298-305
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• 2003

Seasonal variation in species composition of fish in the estuary of Saemangeum water in the western coast of Korea was determined using seasonal samples collected by an otter trawl from April 2001 to February 2002. Species compositions did not differ significantly among the 4 stations (p>0.05, Wilcoxon signed-rank test). The cumulative number of species and species diversity (H') approached asymptote after four 30-min trawl hauls. Therefore 30-min trawl samples from each of the four stations were pooled to represent each season. A total of 45 species 2758 individuals and 30,346.8 g of fish were collected during the study period. Of the fish collected Leiognathus nuchalis, Synechogobius hasta, Neosalanx jordani, Konosirus punctatus and Chaeturichthys stigmatias predominated in abundance accounting for $68\%$ of the total number of individuals. Seasonal variation of fish abundance showed a similar trend to those of the other western coastal waters of Korea. The resident species were collected only in spring and autumn. Number of species and biomass were highest in summer due to the catch of many migrating species. In winter catch amount was low, and only 7 species were collected.. Brackish water fishes were more abundant in the study area, and Johnius grypotus and Cynoglossus joyneri were not premominated compared to the other coastal waters. This difference in species compositions may be related to the lower salinity in this estuarine habitat than in the other western coastal waters of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.529-541
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• 2015

We examined the species composition and community structure of demersal fish in the middle and southern coastal waters of the East Sea of Korea by surveying a commercial Danish seine fishery from 2010 to 2013. We considered the waters north of $37^{\circ}N$ as middle and those south of $37^{\circ}N$ as southern waters. A total of 79 demersal fish species belonging to 18 families were collected. Of these, 59 species (77.6%) inhabited only the East Sea as opposed to the West and South Seas of Korea, and most were resident species. The species and biomass were similar between the two portions of the study area. The sandfish Arctoscopus japonicus (78.0%) and the blackfin flounder Glyptocephalus stelleri (65.1%) were the most common species and accounted for the most biomass in the middle and southern waters, respectively. Fish were most abundant at shallow depths (50-100 m) in the middle portion of the East Sea. Using a cluster analysis, we divided the species composition and community structure at the sampling stations into three groups: middle portion (group A), deep area of the southern portion (group B), and shallow areas of the southern portion (group C). A. japonicas and G. stelleri were dominant in groups A and B, while G. stelleri and Clupea pallasii were dominant in group C.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.3
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• pp.204-216
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• 2018

A study for species composition and abundance of the fish assemblages in the coastal Sacheon Bay, Korea were conducted using monthly collection by a shrimp beam trawl from March 2015 to February 2016. The number of individuals, biomass and species diversity indices fluctuated with the station and month. Of all 73 species collected, the dominant species in terms of numbers were Liparis tanakae, Zoarces gillii, Amblychaeturichthys hexanema, Ricuzenius pinetorum and Pleuronichys cornutus. The peak number of fishes occurred in March and April, whereas the biomass of fishes was highest in April. The numbers and biomass of fishes were lower in February corresponding with the low temperature, and diversity indices were highest in June. Due to those seasonal difference in abundance of the dominant species, fish community were divided into three main groups. In addition, seasonal difference by station of fish community were devided into four main groups. Juvenile fishes of coastal Sacheon were presented during the study period. It presented that the study area served as an important role in spawning and nursery ground for fisheries resource.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.509-517
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• 1986

Abundances of small fishes that utilized eelgrass meadows of Hansilpo, Chungmu, were analyzed to determine fish species composition and monthly changes of this temperate seagrass fish community during 1983-1986. A total of 4,646 fishes that comprised 35 species in 19 families was collected during the period of investigation. Pholis taczanowskii, Pseudoblennius cottoides, Tridentiger trigonocephalus, and Sryngnathus schlegeli predominated in ichthyofauna that occupied the eelgrass meadows most of the year. These four most abundant fish species accounted for approximately $64\%$ of the number of fish collected. Juveniles of economically valuable fish species such as Sebastes inermis, Platycephalus indicus and Limanda yokohamae were also collected in the study area. Seasonal changes in both species composition and abundances of fish populations were major characteristics in these eelgrass meadows. A peak abundance of total fishes occurred during spring, with a secondary peak during fall. The lowest abundance of total fishes occurred in winter. Each abundant fish species showed its own seasonal abundance pattern, and a peak abundance 1-3 months separated from other species with some overlap of the increased larval recruitment.