• Biomedical Science Letters
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• v.7 no.1
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• pp.31-37
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• 2001

The present study was performed to investigate the infection status of heterophyid fluke metacercariae in mullets and gobies collected from some coastal areas of cholla-do. The collected fishes were transferred to the laboratory, artificially digested with pepsin-HCI solution and examined under a stereomicroscope. In 70 mullets examined, the metacercariae of Heterophyes nocens (in 28.6% of fish), Heterophyopsis continua (in 2.9%), Pygidiopsis summa (in 32.9%) and Stictodora spp. (in 14.3%) were detected. The metacercariae of H nocens were detected in mullets from Shinan-gun (in 60.0% of fish), Muan-gun (in 54.4%), Hampyong-gun (in 25.0%) and Yonggwang-gun (in 16.7%). The average metacercarial density per infected fish were 7.6,34, 10 and 5 in each areas. A total of 7 metacercariae of H. continua was detected in only 2 mullets from Hampyong-gun. The metacercariae of p. summa were detected in mullets from Haenam-gun (in 80.0% offish), Muan-gun (in 27.3%), Hampyong-gun (in 16.7%) and Puan-gun (in 100%). The average metacercarial density per infected fish were 350, 14, 5 and 97 in each areas. The metacercariae of Stictodora spp. were detected in mullets from Shinan-gun (in 26.7% offish), Hampyong-gun (in 33.3%) and Puan-gun (in 20.0%). The average metacercarial density per infected fish were 2.8, 18.8 and 2.5 in each areas. In 70 gobies examined, the Metacercariae of H nocens (in 15.7% of fish), H continua (in 47.1%) and Stictodora spp. (in 48.6%) were detected. The metacercariae of H. nocens were detected in gobies from Shinan-gun (in 50.0% of fish) and Yonggwang-gun (in 10.0%). The average metacercarial density per infected fish were 71 and 2 in each areas. The metacercariae of H. continua were detected in gobies from Shinan-gun (in 65.0% of fish), Hampyong-gun (in 70.0%) and Yonggwang-gun (in 60.0%). The average metacercarial density per infected fish were 5.7,6.6 and 3.2 in each areas. The metacercariae of Stictodora spp. were detected in gobies from Shinan-gun (in 80.0% offish), Hampyong-gun (in 70.0%) and Puan-gun (in 40.0%). The average metacercarial density per infected fish were 149,203 and 5.5 in each areas. From the above results, it was confirmed that the mullet and goby from some coastal areas of cholla-do are infected with numerous metacercariae of heterophyid trematodes.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.4
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• pp.324-332
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• 2018

We conducted a questionnaire survey to analyze the current status of the coastal composite fisheries, as well as the improvement point in designing a new type coastal composite fishing boat suitable for Korean fishing environments from April to August 2017. The questionnaire composed of 20 questions about the features of the coastal composite fishing boat and fishing work. The survey sites were selected to cover all parts of the country by considering the geographical position. The significance testing for the response results was accessed by ${\chi}^2$ test and ANOVA. The results revealed that more than half (59.1%) of the fishermen operated one day per voyage and operating alone topped with 22.5% in the number of crews, followed by 2 persons (20.3%) and 5 persons (22.1%). The navigation devices had a high rate of installation and GPS plotter ranked first in the devices. In addition, fish finder ranked first in fishing equipment, followed by net hauler. The most inconvenient work that they felt during the fishing operation was fish handing at 49.8% and other general fishing works like setting and hauling line, deck cleaning accounted for about 25%. The hardest work was the accident by ropes wrapped around propeller and the engine trouble came in second. The most inconvenient facilities to the present design of fishing boat was wheelhouse (76.7%), followed by fish hold (38.5%), and deck (35.1%). Furthermore, inconvenient points related to the movement of fishing gear, noise and vibration of engine, slippery deck and small fish hold exceeded 50%.

• Korean Journal of Ichthyology
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• v.17 no.1
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• pp.84-87
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• 2005

The fish fauna was investigated in the coastal waters of Ulleungdo by SCUBA diving from 27 to 28 July 2004. We observed a total of 45 species from 22 families, including 6 species in Scorpaenidae and 5 species in Labridae. A total of 33 species were recorded at Station 1, and 15 species were recorded at Station 3. As a result of this study, we newly added 23 species to fish list in the coastal waters of Ulleungdo.

• 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.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.132-137
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• 2008

Differential gene expression profiling was carried out in the hepatic tissue of medaka fish, Oryzias latipes, after exposure to an organophosphorus pesticide (OPP), Iprobenfos (IBP), a widely used pesticide in agri- and fish-culture, using a medaka cDNA micro array. Twenty six kinds of differentially expressed candidate genes, with 15 and 11 induced and repressed in their gene expressions, respectively, were associated with cytoskeleton (3.8%), development (7.7%), immune (7.7%), metabolism (30.8%), nucleic acid/protein binding (42.3%) and reproduction (7.7%). Of these genes, changes at the transcription level of five were re-evaluated by real-time quantitative PCR (qRT-PCR). Considering the known function of authentic genes, the effects of IBP on the biological activity and pathological aspects in medaka fish were discussed. The identified genes could be used as molecular biomarkers for biological responses to OPPs contamination in an aquatic environment.

• Ocean Science Journal
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• v.43 no.1
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• pp.9-16
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• 2008

Environmental qualities of coastal water and bottom sediment were assessed at Jordan's northernmost tip of Gulf of Aqaba to evaluate possible impacts of the bordering fish pen cages in Eilat. Results showed significant differences between surface and bottom water in the chemical and physical variables in the different months of the year (2004-2005). Chlorophyll a was also significantly higher in bottom water when compared to that of the offshore water. Nitrate and ammonia were significantly higher in bottom water than the surface water at each individual station. The upper 2 cm of sediment sample recorded higher values of total phosphorus and organic matter. Seasonality affected the content of total phosphorus, organic matter, redox potential and color especially at the sediment layer below 3 cm of the sediment core. The present investigation showed slight modification of water and sediment qualities but no clear sign of eutrophication was observed. However, to maintain sustainability of healthy environmental conditions at the northern tip of Gulf of Aqaba potentials of any possible environmental risks arising from the fish farms or any other coastal investment should be carefully considered.

• Journal of Aquaculture
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• v.16 no.1
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• pp.15-23
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• 2003

We have investigated water quality of the coastal saline groundwaters utilized for fish farms in Jeju Island. The water quality investigation included the spatial observations for 75 fish farms during March-May, 1994 and the hi-monthly observations for both coastal saline groundwaters and seawaters at four fish farms from August 1994 to December 1995. Water temperature of the saline groundwaters ranged from 16 to 18$^{\circ}C$ over the study period. Salinity of the saline groundwaters varied between 20.60 ppt and 34.02 ppt, slightly lower than that of the coastal seawaters(26.47~34.53 ppt). This salinity variation must be associated with local precipitation conditions in Jeju Island. The oxygen saturation for most saline groundwater samples was lower than 80%, ranging from 24.7 to 89.8%. The COD and pH values for the saline groundwaters were similar to those for the coastal seawaters. The concentrations of DIP for the saline groundwaters varied between 0.021 mg/L and 0.121 mg/ L, and seasonal variation of DIP in the saline groundwater ranged from 0.014 to 0.077 mg/L, which were higher than that of the coastal seawaters(0.000~0.015 mg/L). Nitrate in the saline groundwaters accounted for more than 90% of the DIM. The maximum concentrations of ammonia, nitrite, nitrate and DIN in the saline groundwaters were 0.085, 0.012, 2.294 and 2.309 mg/L, respectively. These concentrations of the saline groundwaters were considerably lower than those affected culture organisms. Overall, the saline groundwaters utilized for fish farms in Jeju Island appear to maintain good waterquality for fish farms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.4
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• pp.357-362
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• 2006

The feeding habits of John Dory (Zeus faber) were studied by examining the stomach contents of 317 specimens collected from January 2004 to December 2005 in the coastal waters off Gori, Korea. The standard length (SL) of the specimens ranged from 12 to 42 cm. Z. faber is a piscivore and consumes mainly teleost fish such as Psenopsis anomala, Trichiurus lepturus and Conger myriaster. Its diet also includes shrimp and cephalopods. Smaller individuals (<25 cm SL) consume shrimp and small fish such as Glossanodon semifasciatus. The proportion of these prey items decreases with increasing fish size, and this decrease is paralleled by increased consumption of lager fish such as Psenopsis anomala and Trichiurus lepturus. The prey size increases with Z. faber size.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.3
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• pp.209-219
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• 2016

The survey was conducted to investigate biomass and distribution of fisheries resources using a quantitative echo sounder and a fixed gillnet around Marado coast of Jeju to obtain the scientific basic data for dispute resolution with a large purse seine fishery and coastal fishing and policy establishment of reasonable fisheries resources. Hydroacoustic surveys were conducted six times (November 28~29, 2015 (night), February 23~24, 2016 (night) and March 3~4, 2016 (night/day), March 30~31, 2016 (night/day)) using a quantitative echo sounder. The pelagic fish densities were relatively higher around Marado in November 2015, February 2016 and March 3~4, 2016. However, demersal fish densities were relatively higher in Jeju coastal waters on March 30~31, 2016. Catch data using fixed gill net were used to calculate biomass. Based on the hydroacoustic data, fish length-weight function and target strength information of dominant fish, the biomass of fishes were estimated as follow: 5.64 ton CV = 70.2% at night on November 28-29 2015, 7.14 ton CV = 35.8% of pelagic fish and 530.77 ton CV = 34.6% of demersal fishes at night on February 23-24 2016, 2.34 ton CV = 56.7% of pelagic fish and 571.93 ton CV = 40.3% of demersal fish at daytime, 1.39 ton CV = 48.4% of pelagic fish and 194.59 ton CV = 54.3% of demersal fish at night on March 3~4 2016, 0.37 ton CV = 72.9% of pelagic fish and 338.79 ton CV = 99.7% of demersal fish at daytime, 0.24 ton CV = 21.3% of pelagic fish and 68.61 ton CV = 53.8% of demersal fish at night on March 30~31 2016.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.127-136
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• 2020

The purpose of this study is to measure the productivity of fisheries in China's coastal areas (including inland and marine fisheries) and to analyze the factors influencing the development of fishery economy in each province by comparing regional differences. The input indicators used for efficiency analysis are fish farms, ships and staff numbers, and the output indicators are fish catch and net income. In this paper, we used six years of data from 2013-2018 and DEA-Malmquist index was used to analyze the efficiency of coastal fisheries production in 11 areas of China's coast. According to the analysis from 2013 to 2018, the fishery output efficiency in China's coastal areas has improved to some extent, but most provinces and regions are characterized by technological progress, and the technological efficiency still needs to be further improved. The conclusion can provide reference for the development planning and policy measures of regional fishery industry in China's coastal areas.