• Korean Journal of Ichthyology
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• v.22 no.2
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• pp.105-114
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• 2010

A taxonomic review of the family Sillaginidae was carried out based on two species (Sillago japonica and S. parvisquamis) collected in the coastal waters of Korea from 2008 to 2009 and three species (S. parvisquamis, S. aeolus and S. sihama) kept in the museum. Sillago japonica was easily distinguished from S. parvisquamis and S. sihama by lateral line scales (70~73 in S. japonica vs. 77~81 in S. parvisquamis vs. 67~70 in S. sihama) and scales above lateral line (3~4 vs. 7 vs. 5~6, respectively). Sillago aeolus differed from the other three species in having dark brown blotches on the side of body. We newly found morphological differences in some measurements (snout length, pectoral fin length and $2^{nd}$ anal spine length) and the number of vertebrae between Korean and Japanese S. parvisquamis, suggesting the two may be different populations. Although four sillaginid species are known from Korea, only two species (S. japonica and S. parvisquamis) were found in this study; accordingly, the distribution of the remaining two species (S. sihama and S. aeolus) may be restricted to subtropical waters.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.335-345
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• 2010

Species composition and seasonal variation of fish assemblage in Sacheon marine ranching, Korea were examined. Sampling was seasonally made by a shrimp trawl from February 2009 to November 2009. A total of 55 species were collected. Of these, five species was dominant species comprising 51.1% of the total number of individuals. Nine species represented 57.3% of the total biomass. While total abundance (number of individuals) was high in spring, total biomass and species richness (number of species) and diversity were high in autumn. Cluster analysis, based on seasonally abundance data of the 21 most common species, showed that the species were separated into 4 different groups. Group A composed of Pholis nebulosa, Pleuronectes yokohamae, Hypodytes rubripinnis, Hexagrammos otakii, Tridentiger trigonocephalus and Paracercis sexfasciata, which were year round residents, group B Congr myriaster, Leiognathus nuchalis, and Platycephalus indicus, which were abundant in autumn, group C Sillago japonica, Pseudaesopia japonica, Zoarces gilli, Pholis fangi, and Pleuronichthys cornutus which were abundant in spring, and group D Sillago sihama, Cociella sp., Johnius grypotus, Cynoglossus joyneri, Cynoglossus robustus, and Pennahia argentata, which were abundant in summer. Principal component analysis revealed that seasonal variation in the fish assemblage was attributed to the abundance of temporal species such as conger and sand smelt fishes, which were abundant in summer, due to seasonal variation of water temperature.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.3
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• pp.165-173
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• 2008

Sea experiment for this study was carried out to develop a Trawl Escapement Net(TEN) using net material to improve the survival rate of undersized fishes that escaped from trawls in the Korean southern sea in May and November, 2005. Three kinds of Trawl Escapement Net(TEN) were examined to increase the escapement rate for fishes escaped from the TEN, and total catches in the codend and cover-net were investigated. The main catch species in the experimental fishing trials using a V shape TEN(A type) in May were Korean pomfret(Pampus echinogaster), slimy(Leiognathus nuchalis), gizzard shad(Konosirus punctatus), white croaker(Pennahia argentata) and smelt(Sillago sihama). In the experimental fishing trials using a V shape TEN with a protector for undersized fishes(B type) and a panel shape TEN with a protector(C type) in November, the main catch species were horse mackerel(Trachurus japonicus), sea pike (Sphyraena japonica), large-head hairtail(Trichiurus lepturus), kammal thryssa(Thryssa kammalensis), white croaker(Pennahia argentata), butterfish(Psenopsis anomala) and red gurnard(Lepidotrigla microptera). Most of large-sized fish species like Korean pomfret and Spanish mackerel could not escape through the TEN in the B type and C type. Catches of horse mackerel were highest in the experimental fishing of November and escapement rates for most fish species including horse mackerel were higher in the C type compared with B type.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.332-342
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• 2007

Species composition and quantitative and body length composition of the ichthyoplankton were investigated by samples collected from the coastal waters of uljin in January, April, July and October, 2002. During the study, the collected fish eggs were identified as belonging to 7 taxa. The most of dominant species Engraulis japonicus, were accounted for 38.34% of the total fish eggs, followed by Sillago sihama (25.84%). The collected larvae and juveniles were identified into 25 taxa, 18 families, 7 orders. The domninant species Engraulis japonicus accounted for 90.46% of the total larvae and juveniles, followed by Sebastes schlegeli 2.04%. These 2 taxa constituted 92.50% of the total collected larvae and juveniles. The diversity index of species per months of the collected juveniles the coastal water of Uljin, 2002 was 0.0878~2.3855 and the evenness index was 0.0451~0.9300. in case of dominance index was 0.3000~0.9914 against the evenness index. The analyzed species diversity index by the each stations was 0.3035~0.7440 and the dominance index was 0.8919~0.9669 against the species diversity index. The similarity of community structure per season was very high because of the relative difference (0.010), which was the least in Summer and Fall. In addition, the community structure was very similar in state 1 and state 4 out of each stations because the relative difference was the least, 0.139.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.4
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• pp.1-20
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• 1986

Physical, chemical and biological surveys on Nakdong River estuary were made from October, 1985 to September, 1986. 1. For all the seasons except summer, the sea surface temperature in northwest area of the line which linked from Seo Island to Jisim Island was I-2$^{\circ}$C lower than in southeast area, but in summer the sea surface temperature in northwest area was I-2$^{\circ}$C higher than in southeast area. On the contrary, bottom temperature of coastal area was 1$^{\circ}$C higher than that of oceanic area except winter. 2. Surface salinity in summer and fall has minimum value of 1. 9%0 and maximum value of 32.9%0. This large variation was caused by the runoff of the Nakdong River. Effect of less saline Nakdong River water in northwest area of the line which linked from Seo Island to Jisim Island was greater than in southeast area. A strong current rip always formed near this line. 3. The yellowish-green colored zone was observed in the Nakdong River estuary throughout the year by influence of river discharge. The characteristics of the water quality in the zone have shown that the water color was grade 7 by the Forel water-color meter, transparency was less than 4 m, and concentration of suspended solids was more than 5 mg/1. This water body was in the state of eutrophication in terms of chlorophyll-a and inorganic nitrogen concentration during summer season. 4. During the study period, total 276 taxa were identified. Most of them were diatoms and dinoflagellates which consisted of 97.5%. The component ratio of the above two groups was 84.4% and 13.1 % respectively. Diatoms were plentiful in December and dinoflagellates in July. Dominant species were Nitzschia seriata in October, Thalassiosira rotula in December, Skeletoncma costatum in April, and Nitzschia longissima in July. 5. A total of 47 zooplankton taxa was identified from the samples collected. Copepods were numerically the most important components of zooplankton communities in the study area. The domir:ant copepod species were Paracalanus parvus, Acartia clausi and Temora turbinata. Noctiluca scintillans was the next important component. The other zooplankton with minor abundance were Cladocera. Sagitta spp., Cnidaria, Mysidacea, Lucifer spp. and Amphipoda. 6. During the study period, fishes from 47 families and 87 species were sampled in th~ study area. The four most abundant fish species were Rep~mucen//'s valencicnnei, Leiognathus n~cha!is, Amblychaeturicllthys hexanema and Sardirel/a zun:zsi. The fish species of the secondary importance in abundance were Cynoglossus joyneri, Sillago sihama, Engra~lis japonicus, Encdrias nebulos'l, Acanthogobius flavimanus, Trichiurus lepturus, LiParis tanai/ai, Cynagloss//'s interruptus, Aj)ogon line:z!us, Thrissz la 1l.'1la!ensis, and Limanda yokohamac.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.179-187
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• 1977

This study intended to investigate the shape of the artificial fish reefs settled in the waters of Seogwipo, and the thronging of fish schools into them. The results obtained are summarized as follows : 1. Two types of artifical fish reef, circularized vertical type which is composed of Cryptomeria branches and parachute type, were put off the coast of Seogwipo at $33^{\circ}14'05'$ N Lat., $126^{\circ}34'40'$ E Long. The setting place is located 0.4 sea-mile away from natural fish reefs, at 25 m in depth. And its sediment is consisted of f. S. and Sh. 2. Maximum velocity of wind drift current was 15.28 cm/sec at 15 m depth. The Current direction was $20.5\%$n in the WSW. 3. Maximum fluid resistance of the circularized vertical type to current and wind waves showed about 890 kg, and the weight of sand bags attached to the fish reef totaling 1,200 kg was enough to sustain fish reef. 4. As maximum fluid resistance of the parachute type to current and wind waves was 106.3 kg, the retaining force of sand bags was enough to sustain the fish reef, but vinyl canvas and expansion materials were so poor that the fish reef was lost by the sea current and wind waves. 5. Sixteen species of fish among 53 usually caught in this area were thronged into the artificial fish reef. The fish catches comprized Porgy (Pagrosomus major) $23\%$, black kook fish (Sebastes (Mebarus) intermis) $13\%$, sand borer (Sillago sihama) $11\%$, Sebastes (Pteropodus) hubbsi $7\%$, and file fish (Monacanthus cirrhifer) $6\%$. According to the submarine observations by fivers, it was confirmed that a lot of fish larvae thronged in the middle part of the fish reefs.