• Journal of fish pathology
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• v.14 no.1
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• pp.21-30
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• 2001

From March 1998 to April 2000, 4 species of marine fishes including black rockfish (Sebastes schlegeli), goby (Acanthogobius flavimannus), fine-spooted flounder (Pleuronichthys cornutus), and croaker (Nibea albiflora) were captured from the coastal area of the Gogunsan island located in the mouth of the Kum River, and greenling (Hexagrammos otakii) was sampled from the coastal areas of the Gogunsan island and the Wan-do. Trematodes from the stomach and the intestine of the fishes were detected and identified on the basis of the morphological characteristics. Four species of trematodes were detected in the stomach and the intestine of the examined fishes ; Opecoelus lobatus Ozaki, 1925 from black rockfish, fine-spotted flounder and greenling, Coitoecum glandulosum Yamaguti, 1934 from goby, Phyllodistomum sp. Braun, 1899 from croaker, and Pharyngora sp. Lebour, 1908 from greenling captured from Wan-do. This report gave morphological descriptions of O. lobatus, Pharyngora sp. and Phyllodistomum sp. from coastal marine fishes in Korea.

• Korean Journal of Environmental Biology
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• v.24 no.2 s.62
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• pp.179-185
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• 2006

This study investigated the seasonal changes of body composition and elasticity between wild and cultured brown croaker, Miichthys miiuy. The wild fish were analyzed and compared with cultured fish in moisture, crude protein, lipid, ash and many kinds of amino acids. Cultured fish was higher in moisture content and lower in crude lipid and protein content than those of wild one. The wild fish were more abundant in the total amino acid compositions than those of cultured one. As result E/A ratio there was a little significant differences between wild and cultured. In highly unsaturated fatty acid, EPA (Eicosapentaenoic Acid) and DHA (Docosahexaenoic Acid) content of cultured fish were higher than wild one. On the other hand, the gel strength, max weight and hardness of wild fish were higher than cultured one.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.2
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• pp.95-100
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• 2005

In order to improve the gill nets for croaker, Miichthys miiuy which is proper to the fishermen's income ans fisheries resource management, we had studied to the net height of present gill nets (mesh size 160mm, 50 mesh in depth), experimental gill nets-I(mesh size 150mm, 68 mesh in depth) and experimental gill nets-II(mesh size 142mm, 75 mesh in depth) in wter using the gill nets design ans analysis simulation system, and then investigated and analyzed the catch efficiency of each gill nets through the field fishing experiments. The net height of emperimental gill nets-I and experimental gill nets-II in water were estimated respectively about 1.5 times and 1.3 times higher than present gill nets which the net height is about 3.5m as the results of simulation considering the current of fishing fields. Total number of croakers which were caught by the persent gill nets was 62(body length 300~1,200mm), total catch weight was 398.7kg (mean 0.6kg/sheet). Total number of croakers which were caught by the experimental gill nets- I was 68(body length 600~1,100mm), total catch weight was 391.6kg (mean 1.2kg/sheet). Total number of croakers which were caught by the experimental gill nets-II was 28(body length 400~900mm), total catch weight was 99.2kg (mean 0.3kg/sheet).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.3
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• pp.154-160
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• 1970

The present paper deals with the growth of yellow croaker by scale age reading. This study is based on material from 596 specimens caught by the Danish seine in the Yellow Sea during the period from June 1967 to April 1968. Ring marks of the scale were formed from April to July, corresponding to the spawning season of the fish reported by Bae (1960). Growth rate of each radius of the ring was approximately 0.73. The relationship between the total length and radius of scales, and the relationship between the body weight and total length are represented by the following equations respectively: L=61.350R+50.184 $$W=4.298L^{3.227}\times10^{-3}$$ Maximum total length calculated by the diagram of Walford's growth transformation, $$L_{n+1}=0.6866L_n+10.8730$$, was 346.9mm. Growth curve of the fish can be expressed by the following von Bertalanffy's equation : $$L_t=346.9(1-e^{-0.376(t+0.609)})$$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.621-630
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• 2015

This study investigated the concentration of total mercury in 17 species of commonly consumed fishes and assessed the risk to human health from provisional tolerable weekly intakes PTWI% as affected by migratory characterization, such as migration and vagility. The measured mean concentrations of total mercury in these 17 species of commonly consumed fishes suggest that mean concentrations of total mercury in 10 species of migratory fishes (largehead hairtail, chub mackerel, Pacific saury, skipjack tuna, Pacific cod, anchovy, Alaska pollack, brown croaker, Japanese Spanish mackerel, yellow croaker and Pacific herring) were low compared to those in 7 species of demersal fishes (red stingray, brown sole, bastard halibut, conger eel, blackmouth angler, rockfish and filefish). Based on the mean concentrations, the PTWI% of total mercury among commonly consumed migratory fishes was 3.393%, which was higher than that of commonly consumed demersal fishes (2.710%).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.355-358
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• 2001

This paper presents case studies on the multi-species fisheries in Korean waters. Multi-species fisheries were divided into two types, that is, multi-species by a single fishery and single species by multiple fisheries. For the case of the multi-species by a single fishery, a multi-species yield-per-recruit model was applied to the Korean pair trawl fishery, which exploits demersal fishes such as, hairtail (Trichiurus lepturus), small yellow croaker (Pseudosciaena polyactis), white croaker (Argyrosomus argentatus) and pomfret (Pampus echinogaster). The overall fishing mortality ($F_x$) values for the multi-species was estimated and compared to the spawning potential ratio ($F_{x\%}$) val ues estimated from the spawning biomass-per-recruit model.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.11-19
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• 1975

Yellow croaker, Pseudosciaena manchurica Jordan et Thompson, in the Yellow Sea and the East China Sea are subjected to be caught by trawl nets, stow nets and gill nets throughout the year. Monthly indices of population size are calculated. Mathematic models (I) were used in order to determine catchability coefficient, natural mortality, fishing mortality, coefficient coefficient of the fishing ground and dispersion coefficient from the fishing ground. The results are summarized as follows: 1971 1972 1973 $$Catchability\;coefficient\;(C)=1.9369\times10^{-5}\;7.5459\times10^{-6}\;1.2670\times10^{-5}$$ Natural mortality (M) = 0.1645 0.6152 0.4367 Population for the first half season (February 1 to May 31) 1971 1972 1973 Initial\;population=\;107,100M/T 209,100M/T 214,400M/T Dispersion=83,000' 159,700' 133,400' Natural mortailty= 4,700' 32.700' 19,100' Final population= 2,800' 4,500' 49,000' Population for the latter half season (June 1st to the following January 31st) 1971 1972 1973 Initial population= 44,500M/T 67,500M/T 83,800MT Recruitment= 19,000' 183,900' 67,100' Natural mortality= 5,900' 67,900' 38,500' Final population= 37,000' 168,300' 92,400'.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.6
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• pp.478-484
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• 2004

On 11 June 1991, eggs from the brood stock of small yellow croaker (Larimichthys polyactis) were artificially fertilized using the standard dry method and were hatched. Each of the fertilized eggs (1.1-1.2 mm in diameter) had an oil globule and was transparent and buoyant. The fertilized eggs hatched in a range of water temperatures $(17.5-20.3^{\circ}C)$ 44 hrs after fertilization. The total lengths of the newly hatched larvae were 3.1-3.3 mm, and these hatchlings had 31 myotomes (10+21). Melanophores and yellow-brown chromatophores were concentrated on the head, at the ventral part of the yolk, and in the middle of the tail. Four days after hatching, the larvae completely absorbed the yolk and became flexions of 5.1-5.5 mm in total length. Fifteen days after hatching, one spine (the anterior tip of the maxillary) appeared in the upper jaw and three spines developed at the upper parts of the eyes and on the posterior part of the head. At this stage, the larvae were approximately 8.3 mm long. Thirty-nine days after hatching, juveniles (1.9-3.4 mm in total length) had a pointed tail fin. By 66 days after hatching, the juvenile fish (about 4.0-6.5 mm in total length) were similar to adult fish in body shape. The larvae of L. polyactis could be distinguished from those of L. croacea by two distinct characteristics: the large number of vertebrae (28-29), and a relatively small bony ridge on the occipital region of the head.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.499-505
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• 2011

The fishing grounds of Korean large-pair trawlers have shifted since exclusive economic zones (EEZs) were established in a fisheries agreement involving countries neighboring Korean waters. The distributions of marine ecosystems and fisheries resources have been changing with environmental changes such as global warming and with the shift in species targeted as a result of changes in fishing technology and fishing gear. This study analyzed variation in the species assemblages caught in Korean waters by large-pair trawlers as a result of these geopolitical and environmental changes. The data used in this study were obtained from the Fishery Production Statistics of Korea and the Port Sample Survey of the National Fisheries Research and Development Institute (NFRDI) from 1990 to 2007. Hierarchical clustering analysis (HCA) and correspondence analysis (CA) were used to explore the characteristics of the catch-species composition. The overall variation in the species composition of the catch of Korean large-pair trawlers showed that the proportions of croaker Johnius grypotus, small yellow croaker Larimichthys polyactis, eel Anguilla japonica, and blue crab Portunus trituberculatus decreased, whereas those of hairtail Trichiurus lepturus, Spanish mackerel Scomberomorus niphonius, anchovy Engraulis japonicus, and common squid Todarodes pacificus increased in Korean waters over the 18-year period. The results of the HCA of the annual catch data by species showed four different distributions of fish species according to year. Results of the CA showed that the species assemblages differed between the 1990s and 2000s.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.541-555
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• 2016

This study determined the concentrations of lead and cadmium in 18 species of commonly consumed fish and assessed the risk based on provisional tolerable weekly (monthly) intakes [PTW(M)I] % as affected by behavioral characteristics, such as migration and settlement. In the 18 species, the mean concentrations of lead and cadmium were higher in the 11 species of migratory fish (llargehead hairtail Trichiurus lepturus, chub mackerel Scomber japonicus, Pacific saury Cololabis saira, skipjack tuna Katsuwonus pelamis, Pacific cod Gadus macrocephalus, anchovy Engraulis japonicus, Alaska pollack Theragra chalcogramm, brown croaker Miichthys miiuy, Japanese Spanish mackerel Scomberomorus niphonius, yellow croaker Larimichthys polyactis, and Pacific herring Clupea pallasii) than in the seven demersal species (red stingray Dasyatis akajei, brown sole Pleuronectes herzensteini, bastard halibut Paralichthys olivaceus, conger eel Conger myriaster, blackmouth angler Lophiomus setigerus, rockfish Sebastes schlegelii, and filefish Stephanolepis cirrhifer). Based on the mean concentrations, the PTWI % of lead and cadmium in commonly consumed migratory fish were 1.900 and 2.986%, respectively, which were higher than the values for lead and cadmium in the commonly consumed demersal fishes (0.257 and 0.318%, respectively). The estimation of weekly (monthly) intakes and target hazard quotients for the toxic elements lead and cadmium revealed that the commonly consumed migratory and demersal fish do not pose any health risks for consumers.