• Fisheries and Aquatic Sciences
• /
• v.11 no.1
• /
• pp.61-69
• /
• 2008

Using empirical data of fish performance and physiological limits as well as physical stimuli and environmental data, a cod-end selectivity model based on a chaotic behavior model using the psycho-hydraulic wheel and neural-network approach was established to predict fish escape or herding responses in trawl and cod-end designs. Fish responses in the cod-end were categorized as escape or herding reactions based on their relative positions and reactions to the net wall. Fish movements were regulated by three factors: escape time, a visual looming effect, and an index of body girth-mesh size. The model was applied to haddock in a North Sea bottom trawl including frequencies of movement components, swimming speed, angular velocity, distance to net wall, and the caught-fish ratio; simulation results were similar to field observations. The ratio of retained fish in the cod-end was limited to 37-95% by optomotor coefficient values of 0.3-1.0 and to 13-67% by looming coefficient values of 0.1-1.0. The selectivity curves generated by this model were sensitive to changes in mesh size, towing speed, mesh type, and mesh shape.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.41 no.3
• /
• pp.221-227
• /
• 2008

The black rockfish (Sebastes schlegeli) is an important commercial species in Korean fisheries. We used acoustic telemetry using coded ultrasonic transmitters to track the home ranges and homing routes of the black rockfish that inhabit in the Tongyeong marine ranching area. Twenty-four fish were released at five points. The distance from the capture point (C1) to the released point was 0 (R7), 0.2 (R1), 0.9 (R2), 1.3 (R3) and 1.9 (R4) km. Two of the three fish released at R1 (0.2 km) returned home in under 48hrs. Another was found 0.8km from C1. Two of the five fish released at R2 returned home, but it took over 250 days. None of the ten fish released at R3 and R4 returned home. Three of the ten fish moved 1.1-2.6 km from C1 and were found near a cage or a natural reef. Six fish were released at R7. The younger the fish, the wider was its movement range around the artificial reefs. Fish over 3 years old were likely to move less far.

• Journal of fish pathology
• /
• v.18 no.1
• /
• pp.59-66
• /
• 2005

In the present paper, the immunostimulatory effects of Korean mistletoe (Viscum album Coloratum) on the non-specific immune responses of Japanese eel (Anguilla japonica) were examined. Eel were innoculated with mistletoe, Freund's complete adjuvant (FCA), or phosphate-buffered saline (PBS) as a control into their peritoneal cavities. The number of nitrobule tetrazolium (NBT)-positive cells in the head kidney of fish was significantly increased by the second day post-injection of mistletoe. ROI products were more enhanced in mistletoe-injected fish kidney leucocytes than in FCA-injected ones. The level of lysozyme activity detected in the serum of fish 2 days after injection with mistletoe was also significantly higher than that found in the serum of the control fish. The appropriate concentration of mistletoe to induce the highest level of serum lysozyme activity was revealed to 1000${\mu}g$/200 g of fish. In phagocytic activity assay, mistletoe-sensitized eel kidney phagocytes captured more zymosan than did the control fish. Korean mistletoe appeared to be a good activator of the non-specific immune responses of Japanese eel.

• Fisheries and Aquatic Sciences
• /
• v.27 no.5
• /
• pp.276-282
• /
• 2024

The present study was conducted to investigate the behavior and distribution characteristics of fishes near an artificial reef close to the waters of Uljin marine ranch. A 200-kHz, dual-beam frequency transducer was attached to the side of a ship for acoustic measurements. The fish formed small groups in the bottom layer near the artificial reef around the afternoon-sunset period; at night, the fish did not form groups and remained individually scattered. During dawn-sunrise and morning, the fish formed groups again and were found near the upper and middle layers of the artificial reef. High density of fish occurred near the middle of the nautical zone during morning, afternoon-sunset, and dawn-sunrise, periods; at nighttime, the distribution was uniform across the entire zone. Moreover, the mean Nautical Area Scattering Coefficients (NASC, m²/nmi²) value was highest during dawn-sunrise at 400.2 m²/nmi², similar during night and morning (100.5 m²/nmi²), and lowest during afternoon-sunset (20.1 m²/nmi²). The present study is expected to provide the background for understanding the behavioral characteristics of fish living near artificial reefs and estimating the density and biomass of fish.

• Journal of Fisheries and Marine Sciences Education
• /
• v.26 no.5
• /
• pp.959-965
• /
• 2014

Transporting of live fish requires subcontract with an independent contractor. During the transporting of live fish, civil liability problems can be caused by damage of fish. Before transporting of live fish, responsibility of negligence and tort liability were arisen, after transporting of live fish, default on an obligation was arisen. To avoid this problems, it is important to put a bond on each other and live fish transporting contract can be made a legal contract. Also, transporting of live fish must be made safe, after transporting, and discharge of obligation, perfect transaction is achieved.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.50 no.4
• /
• pp.429-436
• /
• 2017

The seasonal and interannual variations in fish assemblages in the coastal waters off Gijang were examined with an otter trawl from 2015 to 2016. A total of 59 fish species was collected during the study period. The dominant species were Caelorinchus multispinulosus, Clupea pallasii pallasii and Chelidonichthys spinosus. Seasonal changes in fish assemblages appeared to be distinct in the study area. The fish assemblages in summer and autumn were clearly distinguishable from those in other seasons, and the largest numbers of species and individuals were captured in winter and summer, respectively. Because fish assemblages are closely related to changes in water temperature, long-term changes in water temperature can have a significant impact on the productivity of offshore fisheries by changing fish species composition, habitat migration, and growth rate of fish.

• Fisheries and Aquatic Sciences
• /
• v.9 no.2
• /
• pp.91-96
• /
• 2006

The movement range and diurnal behavior of 17 wild black rockfish (Sebastes schlegeli) were monitored within the marine ranching area of Tongyeong from 27 July to 7 November, 2005 using acoustic telemetry. Coded transmitters were surgically implanted into the abdomen of fish. Two of ten fish released in summer moved about 2 km away from the capture point for 1 day. The others stayed within a 500-m radius of the release point for 1 week after release. The seven fish released in autumn stayed within 500 m of the release point. Most fish were more active and had a greater range of horizontal diurnal movement at night than during the day. Additionally, the range of horizontal diurnal variation was greater in summer than in autumn. While fish released in summer were more vertically active at night than during the day, those released in autumn preferred to move vertically during the day.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.36 no.4
• /
• pp.346-351
• /
• 2003

Single-cell gel electrophoresis (comet assay) was used to detect DNA single strand break in blood cells from several marine fish species. Three fish species were collected from Georgia coastal area. Mummichog, Fundulus heteroclitus showed higher DNA damage than sea bass, Lateolabrax japonicus and trout, Oncorhynchus masou masou under the same experimental conditions. Mummichogs had more alkaline-labile sites on their DNA than other fish species. The comet assay with mummichog blood cells at pH 12.5 showed a dose-response curve with the increasing concentrations of hydrogen peroxide. While the isolated leucocytes showed no increase of DNA damage after in vitro exposure to 2-methyl-1,4-naphthoquinone (MNQ), erythrocytes showed dose-dependent DNA damage. These results indicate that the comet assay can be applied successfully as a bioassay using erythrocyte for environmental monitoring.

• Journal of Fisheries and Marine Sciences Education
• /
• v.27 no.5
• /
• pp.1499-1507
• /
• 2015

The aim of this study is to research on the recognitions and preferences of Puffer fish consumers with the recently increasing well-being trend. To carry out this research, the main analysis was focused on two specific points: how much consumers perceive swellfish and which kinds of Puffer fish foods are preferred by consumers. Although the consumption of Puffer fish is gradually expending, at the same time, there are also numerous obstructive elements in consuming swellfish. In this regard, this test on Puffer fish food will be able to contribute to show an outlook for the Puffer fish food market in the future and to promote consumption of Puffer fish as well. Methodologically, a statistical research was adopted to find out how people understand Puffer fish and the patterns of their choices and intensive examinations were conducted throughout the collected questionnaire. For a more effective outcome, it was necessary to divide into two groups, the Nation's capital area with Seoul as a center, the most densely populated area and Busan, the biggest marine products consumption area, examining the inclination to consume with regions. In the concrete, the detailed research survey on the Puffer fish were performed with the opinions of the five hundred people from capital area and the five hundred people from Busan area. The difference and common features of consumer's recognition about Puffer fish food were founded through cross analysis according to age, gender, regions, and income. In conclusion, this research showed the difference tastes and recognition standards toward Puffer fish among consumers from Seoul and Busan areas. If it is possible to apply this result to the efforts of improving supplier's understanding about Puffer fish consumers' features and cultivating new Puffer fish items, it could contribute to the further consumption of Puffer fish food in the long term point of view.

• Fisheries and Aquatic Sciences
• /
• v.19 no.5
• /
• pp.25.1-25.8
• /
• 2016

The fractionation of serine protease inhibitor (SPI) from fish roe extracts was carried out using polyethylene glycol-4000 (PEG4000) precipitation. The protease inhibitory activity of extracts and PEG fractions from Alaska pollock (AP), bastard halibut (BH), skipjack tuna (ST), and yellowfin tuna (YT) roes were determined against target proteases. All of the roe extracts showed inhibitory activity toward bromelain (BR), chymotrypsin (CH), trypsin (TR), papain-EDTA (PED), and alcalase (AL) as target proteases. PEG fractions, which have positive inhibitory activity and high recovery (%), were the PEG1 fraction (0-5 %, w/v) against cysteine proteases (BR and PA) and the PEG4 fraction (20-40 %, w/v) against serine proteases (CH and TR). The strongest specific inhibitory activity toward CH and TR of PEG4 fractions was AP (9278 and 1170 U/mg) followed by ST (6687 and 2064 U/mg), YT (3951 and 1536 U/mg), and BH (538 and 98 U/mg). The inhibitory activity of serine protease in extracts and PEG fractions from fish roe was stronger than that of cysteine protease toward common casein substrate. Therefore, SPI is mainly distributed in fish roe and PEG fractionation effectively isolated the SPI from fish roes.