• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.3
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• pp.188-199
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• 2013

This thesis is the fundamental study on the adaptation of escape device for reducing small size of fish in set-net. The escape devices for experiments were made the grid-type devices with three different slit sizes (15, 20 and 25mm). The experiments of size selectivity on escape devices were conducted by using two kinds of species as black rockfish (Sebastes schlegeli) and sea perch (Lateolabrax maculatusi) in the experimental tank. The size selectivity curve was fitted by using a logistic function and the parameters of selectivity curve were estimated by a maximum likelihood method. In the results; 50% selection ranges for the grid-type escape devices with three different slit sizes were; a black rockfish was 13.30, 19.22 and 22.06cm and a sea perch was 17.64, 20.91 and 22.78cm, respectively. The 50% selection range of a black rockfish was wilder than a sea perch about 1.1~1.3 time. Therefore, the small size of fish are able to reduce by using the grid type escape device. However, the optimum slit size of grid should be decided to consider the size of target species and economics of catches.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.1
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• pp.35-40
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• 1985

The author carried out experiments to find out the response of rock bream, Oplegnathus fasciatus (TEMMINCK et SCHLEGEL) and sea bass, Epinephelus septemfasciatus (THUNBERG) to the color nettings. The experimental water tank(180L$\times$50W$\times$55Hcm) was set up n a dark room and water level was maintained 50cm high from the bottom. The tank was devided three longitudinal sections marking 60 cm interval. The illumination systems, consisted of 20 watt fluorescent lamps and filter, were suspended adove the tank. Two different color nettings selected from five colors (red, yellow, green, blue, black) were placed in each end section of the tank. Ten fish were used in each experiment and the fish were acclimatized in the dark for 60 minutes before experiment. After the light on, the number of fish in each section of the tank was counted in every 30 seconds interval for 30 minutes. The results obtained are as follows: 1. The rock bream selected the color nettings in the order of yellow, black, blue, green and red. 2. The sea bass selected the color nettings in the order of green, black, red, blue and yellow.

• The Korean Journal of Food & Health Convergence
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• v.6 no.1
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• pp.21-27
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• 2020

The levels of five heavy metals (mercury, cadmium, lead, copper and zinc) were analyzed in edible tissues of Lophius piscatorius Linnaeus, 1758 marketed in Sinop coasts of the Black Sea by using inductively coupled plasma mass spectrometry. With the present study, heavy metal values of this fish in the Black Sea were examined for the first time. The mean concentrations in mg kg^-1 wet wt. of Hg, Cd, Pb, Cu and Zn were 0.022, 0.009, 0.035, 6.3 and 16 mg kg^-1 wet wt., respectively. The results of the present study indicate that the consumption of muscle from anglerfish can be considered safe in terms of permissible legal limits. It is clear that, Zn showed the high accumulation in muscle tissue followed by Cu, while non-essential metals Hg, Cd and Pb showed the low accumulation. This could be explained by the fact that Zn and Cu are essential elements in the bodies of living organisms and has an important role in different physiological processes. In the present study, heavy metal levels in angler fish were low. Likewise, the calculated HI values were lower than one. In conclusion, the results of the present study indicate that the consumption of muscle from anglerfish can be considered safe in terms of permissible legal limits and hazard index values.

• Ocean Systems Engineering
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• v.8 no.1
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• pp.1-20
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• 2018

The target area of the proposed study, Mamaia beach, is a narrow stretch of sand barrier island that sits between the Siutghiol Lake and the Black Sea. In the northern part of the bay, is located the Midia Port, where between 1966 and 1971 a long extension of 5 km of the offshore was built. Because of this extension, the natural flow of sediments has been significantly changed. Thus, the southern part of the Mamaia Bay had less sand nourishment which meant that the coast was eroding and to prevent it a protection of six dikes was built. After approximately forty years of coastal erosion, the south of the Mamaia Bay had in 2016 a new protection scheme, which includes first of all the beach nourishment and a new dike structure (groins scheme for protection) to protect it. From this perspective, the objective of the proposed study is to evaluate the effectiveness of the old Master plan against the new one by modeling the outcome of the two scenarios and to perform a comparison with a third one, in which the protection dikes do not exist and only the artificial nourishment has been done. In order to assess the wave processes and the current patterns along the shoreline, a complex computational framework has been applied in the target area. This joins the SWAN spectral phase averaged model with the 1D surf model. Furthermore, new UAV technology was also used to map out, chart and validate the numerical model outputs within the target zone for a better evaluation of the trends expected in the shoreline dynamics.

• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.142-147
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• 2021

A single specimen (52.5 mm SL) of Neoclinus chihiroe, belonging to the family Chaenopsidae, was firstly collected from Dokdo, East Sea of Korea on 9 December 2020. This species was characterized by a black spot between the first and the second dorsal spines, and a black spot on upper part of opercular membrane. The species was morphologically similar to N. okazakii, but distinctly distinguished by pectoral fin base without a black dot. This study documents the first record of N. chihiroe in Korean waters and suggests the new Korean name 'Dong-hae-bi-neul-be-do-la-chi' for the species.

• Journal of fish pathology
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• v.15 no.1
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• pp.43-48
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• 2002

A blood biochemical analysis was carried out for the serum of wintering sea bream (red sea bream Pagrus major, black sea bream Acanthopagrus schlegeli, rock bream Oplegenathus fasciantuas) with green liver syndrome. GOT and GPT were significantaly elavated in the diseased sea bream. The value of $NH_{3}$ was slightly higher but those of TBIL. TP and UA were lower than the control. But there were no differences in albumin. Ca and glucose between the diseased and the control. These results suggent that a green liver syndrome in the sea bream might be related with nutritional defects and the stress of low water temperature during the winter.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.2
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• pp.66-71
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• 2006

Fluoroquinoles have a wide range of antimicrobial properties and are effective in the treatment of bacterial diseases in fish. The use of fluoroquinoles continues to grow steadily. Fluoroquinolone antibiotics are probably the most important class used among synthetic antibiotics in human and veterinary medicines because of their broad activity spectrum and good oral absorption. This study was conducted to estimate the residue of antibiotics in four species of farmed fishes, including olive flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli), red sea bream (Pagrus major), and sea bass (Lateolabrax japonicus), collected from fish farms located in the southern coastal area of Korea. The residues of fluoroquinolones were determined using high performance liquid chromatography (HPLC) with a fluorescence detector. Residuals of five fluoroquinolones in muscle tissue of farmed fish were analyzed. We found that enrofloxacin was the most common agent in fish muscle, and that ciprofloxacin was the next most common. The range of detected concentrations of fluoroquinolones in olive flounder muscle was 0-0.859 mg/kg in 32.6% of all samples. Enrofloxacin was commonly detected in sea bass muscle at a range of 0-0.143 mg/kg in 38.9% of all samples. Fluoroquinolones were detected in 6.9% of black rock fish muscle and in 16.6% of sea bream, although the detected concentration was below 0.01 mg/kg. The maximum detection value of enrofloxacin and ofloxacin in olive flounder at the time of shipping was 0.102 mg/kg and 0.09 mg/kg, respectively; no other antimicrobials were detected. We detected no antimicrobial substances in red sea bream.

• Journal of Aquaculture
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• v.20 no.2
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• pp.90-95
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• 2007

Artificially-produced juvenile black sea bream, Acanthopagrus schlegeli (total length $10.4{\pm}1.1\;cm$, body weight $18.7{\pm}3.4\;g$) were released into the Gamak Bay in Korea. And their initial feeding habits and body compositions were compared with those of cultured fish (CUL) for a period of one month after release. The released black sea bream commenced feeding on the 1st day after release, and predation rate was more than 80% during the sampling period. The stomach content of fish was composed of mainly fishing bait and krill in fish sampled on 15th days after release; however, its content changed to the natural organisms such as algae and small crustaceans when the fish was sampled on 20th days after release. Crude lipid content of carcass of fish in the sampling station A (SA) were lower than that of fish in the initial, sampling station B (SB) and CUL for the 5th and 10th days after release. Carcass n-3 HUFA composition, total amino acid and essential amino acid contents of released fish showed high trend compared to that of cultured fish in 30th days after release. The released fish have the ability to adjust their feeding habits and biochemical metabolism to the natural environment within a short period even though they showed preference to artificial feed in the early days after release.

• Animal cells and systems
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• v.2 no.2
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• pp.195-201
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• 1998

The tube anemone, Cerianthus filiformis Carlgren, was collected from nine localities in the Yellow Sea and the Korea Strait (the South Sea). Populations at different localities showed color variations in tentacles from pale brown to violet. This species is redescribed here because it shows the color variation and the association with the phoronid, Phoronis australis, which was newly recorded from Korean waters. The phoronid has black to purple tentacles shaded with the same color as the cerianthid's tube for mimicking.

• Journal of Aquaculture
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• v.21 no.4
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• pp.278-284
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• 2008

Artificially-produced juvenile black sea bream Acanthopagrus schlegeli (total length $8.3{\pm}1.0\;cm$, body weight $11.2{\pm}4.2\;g$) were released in eelgrass, Zostera marina bed and their initial food organism and changes of body compositions were investigated for one month after release. Predation rates in fish sampled on 1st and 3rd days were 79%, increased up to 100% on 7th and 10th days, and then decreased on 30th days as 75%. Major prey organisms was composed of mainly Amphipoda and Gastropoda. Ratio of Amphipoda and Gastropoda in stomach were highest in fish sampled on 15th and 1st days after release, respectively. Crustacea and Algae were maintained about 20% during a sampling period. Visceral weight index (VWI) offish sampled 20th and 30th after release were significantly higher than that of initial. Carcass crude protein and lipid contents of released fish were showed significantly decreasing; however carcass n-3 HUFA composition was showed increasing tendency with the passage of time after release. Eelgrass bed was supposed to be helpful for the released fish to adjust their feeding habits and biochemical metabolism to the natural environment within a short period after release.