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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Journal of Fisheries and Aquatic Sciences
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Journal DOI :
The Korean Society of Fisheries and Aquatic Science
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Volume & Issues
Volume 49, Issue 4 - Aug 2016
Volume 49, Issue 3 - Jun 2016
Volume 49, Issue 2 - Apr 2016
Volume 49, Issue 1 - Feb 2016
Selecting the target year
Nutritional and Microbiological Characterization of Fish Jerky Produced Using Frame Muscle of the Sea Rainbow Trout Oncorhynchus mykiss
Kim, Min Woo ; Kim, Yong Jung ; Kim, Min Joo ; Lee, Su Gwang ; Park, Sun Young ; Choi, Byeong Dae ; Heu, Min Soo ; Kim, Jin-Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 263~269
DOI : 10.5657/KFAS.2016.0263
Large quantities of by-products—such as fish frame, head, skin and viscera—are generated during seafood processing, and these by-products are not utilized extensively. Therefore, sea rainbow trout Oncorhynchus mykiss (SRT) frame muscle (FM) jerky was prepared by grinding SRT-FM, followed by mixing with seasoning, forming and drying. The nutritional and microbiological characteristics of the SRT-FM jerky were then investigated. The proximate composition of the SRT-FM jerky was 19.1% moisture, 38.7% crude protein, 7.9% crude lipid and 4.4% ash. The viable bacterium count of the SRT-FM jerky was 3.9 log CFU/g, and Escherichia coli and Staphylococcus aureus were not detected. The total amino acid content of SRT-FM jerky was 37.3 g/100 g, and the major amino acids were aspartic acid, glutamic acid, leucine and lysine. Based on the recommended daily intake of fish jerky (100 g), the most abundant mineral was potassium. The fatty acid composition of the SRT-FM jerky was 26.2% saturated acid, 34.5% monoenoic acid and 39.3% polyenoic acid, and the major fatty acids were 16:0, 18:1n-9, 18:2n-6, 20:5n-3 and 22:6n-3. These results suggest that SRT-FM jerky has high nutritional value.
Sensory Characterization of Fish Jerky Produced from Frame Muscle of the Sea Rainbow Trout Oncorhynchus mykiss
Kim, Yong Jung ; Kim, Min Woo ; Kim, Min Joo ; Lee, Su Gwang ; Park, Sun Young ; Kim, Jin-Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 270~276
DOI : 10.5657/KFAS.2016.0270
This study investigated the sensory characteristics (texture, odor, taste and color) of jerky produced from ground sea rainbow trout (SRT) Oncorhynchus mykiss frame muscle (FM). The hardness of the ground SRT-FM jerky was 453.9±91.0 g/cm
, which was lower than that of commercial animal jerky (893.5±404.6 g/cm
) and commercial fish jerky (1,394.4±363.5 g/cm
). The difference in the hardness values of the ground SRT-FM jerky and commercial animal jerky was not significant. The volatile basic nitrogen content of the ground SRT-FM jerky was 48.3±1.6 mg/100 g, which was higher than that of commercial fish jerky (21.6±6.2 mg/100 g) and commercial animal jerky (18.2±6.3 mg/100 g). However, the fish odor of the ground SRT-FM jerky was masked by the presence of various additives. The hydrophilic and lipophilic browning indices of the ground SRT-FM jerky were higher than those of the commercial jerky. The total taste value of the ground SRT-FM jerky was 169.0, and the major amino acids were glutamic acid and aspartic acid. These results suggest that ground SRT-FM jerky would be acceptable to consumers.
The Quality Characteristics and Processing of Madeleine Containing Red Snow Crab Chionoecetes japonicaus Leg-Meat Powder
Kim, Byoung-Mok ; Jung, Min-Jeong ; Jun, Joon-Young ; Kim, Dong-Soo ; Jeong, In-Hak ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 277~284
DOI : 10.5657/KFAS.2016.0277
In this study, we investigated the quality characteristics of madeleine combined with lyophilized red snow crab Chionoecetes japonicus leg-meat powder (CM). The madeleine was prepared by the addition of wheat flour containing 0, 1, 5, 10, 15 and 20% concentrations of CM. Moisture content, pH, and baking loss rate did not differ significantly among groups. Light coloration significantly decreased in a dose-dependent manner, while red and yellow coloration significantly increased. Hardness, chewiness and gumminess significantly increased in a dose-dependent manner, while cohesiveness, springiness and adhesiveness did not differ from CON (madeleine containing 0% CM). In terms of sensory characteristics, appearance and color did not differ compared to CON, while taste, flavor and overall preference increased in a dose-dependent manner, with CM10 having the highest score among the groups. The present study assesses the potential of this improved formula as a convenience food.
Effects of Red Snow Crab Chionoecetes japonicus Leg Meat Powder on the Quality Characteristics of Noodles
Kim, Byoung-Mok ; Jung, Min-Jeong ; Kim, Jong-Chan ; Jun, Joon-Young ; Kim, Dong-Soo ; Jeong, In-Hak ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 285~292
DOI : 10.5657/KFAS.2016.0285
In this study, we investigated the quality characteristics of noodles supplemented with lyophilized leg-meat powder from the red snow crab, Chionoecetes japonicus (CP). The noodles were prepared by adding 0, 2, 4, 6, 8, 10% of CP on a wheat-flour basis. The ash, crude protein and crude lipid contents of noodles increased with increasing CP content. The cooked weight, volume and water absorption values of noodles decreased, whereas the turbidity increased, with increasing CP content. The L values of the noodles decreased with increasing CP content, whereas the a and b color values increased. The hardness, gumminess and chewiness values increased with increasing CP content increased, while springiness and cohesiveness showed no significant differences among the groups. In the sensory evaluation, cooked noodles with 4-6% CP had greater overall acceptability than the noodles with other CP levels.
Processing and Characteristics of Snacks Make from Extrusion Rice Oryza sativa and Dried Shrimp Acetes chinensis
Je, Hae-Soo ; Kang, Kyung-Hun ; Jung, Hee-Bum ; Park, Si-Young ; Kang, Young-Mi ; Seoung, Tae-Jong ; Lee, Jae-Dong ; Park, Jin-Hyo ; Kim, Jeong-Gyun ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 293~300
DOI : 10.5657/KFAS.2016.0293
In the present study, we investigated the quality, sensory characteristics and commercialization potential of a rice collet snack made with the addition of dried shrimp. “Mild” and “spicy” snack products were produced with an edible oil coating and mixed seasoning powder coating, respectively. The approximate composition of the mild and spicy snacks, respectively, were 2.44% and 2.24% for moisture, 8.52% and 8.64% for crude protein, 18.36% and 26.54% for crude lipids, 1.28% and 1.38% for ash, 1.1% and 1.2% for salt, and 0.61 and 0.62 for pH. The L (lightness), a (redness), b (yellowness), and ⊿E (color difference) values were higher for the mild snack than the spicy snack. The mild and spicy snack had values of 7,776.4 and 7,655.8 mg/100 g for total amino acids, and 221.6 and 253.5 mg/100 g for total free amino acids, respectively. The TBA (thiobarbituric acid) value did not differ significantly between the two types of snack. The hardness value of the spicy snack was higher than that of the mild snack, but there were no significant differences in flavor between the two products. The sensory evaluation score of the spicy snack was slightly higher than that of the mild snack. Organoleptic inspection indicated that both snacks had a favorable, unique taste.
Characterization of Calcium Lactate Prepared from Butter Clam Saxidomus purpuratus Shell Powder
Yoon, In Seong ; Lee, Gyoon-Woo ; Lee, Hyun Ji ; Park, Sung Hwan ; Park, Sun Young ; Lee, Su Gwang ; Kim, Jin-Soo ; Heu, Min Soo ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 301~309
DOI : 10.5657/KFAS.2016.0301
To facilitate the effective use of butter clam shell as a natural calcium resource, we determined the optimal conditions for calcium lactate (BCCL) preparation with high solubility using response surface methodology (RSM). The polynomial models developed by RSM for pH, solubility and yield were highly effective in describing the relationships between factors (P<0.05). Increased molar ratios of calcined powder (BCCP) from butter clam shell led to reduced solubility, yield, color values and overall quality. The critical values of multiple response optimization to independent variables were 1.75 M and 0.94 M for lactic acid and BCCP, respectively. The actual values (pH 7.23, 97.42% for solubility and 423.22% for yield) under optimization conditions were similar to the predicted values. White indices of BCCLs were in the range of 86.70–90.86. Therefore, organic acid treatment improved color value. The buffering capacity of BCCLs was strong, at pH 2.82 to 3.80, upon the addition of less than 2 mL of 1 N HCl. The calcium content and solubility of BCCLs were 6.2–16.7 g/100 g and 93.6-98.5%, respectively. Fourier transform analysis of infrared spectroscopy data identified BCCL as calcium lactate pentahydrate, and the analysis of microstructure by field emission scanning electron microscopy revealed an irregular form.
Processing and Quality Characteristics of Glutinous Barley Gruel Containing Hizikia fusiformis
Lee, Yeon-Ji ; Lim, Seung-Yong ; Kim, Won-Suk ; Kim, Yong-Tae ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 310~316
DOI : 10.5657/KFAS.2016.0310
This study was conducted to evaluate the physicochemical characteristics, perform a sensory evaluation of glutinous barley gruel after adding Hizikia fusiformis powder to promote consumption, and identify the best ratio and recipe. The gruel was prepared with rice and glutinous barley powder, and various levels (0, 2.5, 5.0, and 7.5%) of H. fusiformis powder. pH, color, viscosity, and spreadability of the gruel were investigated. A sensory evaluation was conducted by 20 panelists in the categories of color, flavor, taste, texture appearance, and overall preference using a 9-point hedonic scale. The viscosity and pH of the gruel increased as H. fusiformis powder content increased, whereas spreadability of the gruel decreased gradually as H. fusiformis powder content increased. As the level of H. fusiformis powder increased, lightness decreased significantly, whereas redness and yellowness increased. Color, bitter taste, and H. fusiformis flavor of the gruel increased significantly as H. fusiformis powder content increased. On the other hand, sweet taste (delicious taste level) and viscosity were not different among the different gruels. The sensory test results indicated that the gruel with 5% H. fusiformis powder had the best overall acceptability. In conclusion, glutinous barley gruel with 5% added H. fusiformis powder was more acceptable than the others.
Influences of Different Dietary Lipid Sources on the Growth, Body Composition, and Fatty Acid Profiles of Juvenile Fancy Carp Cyprinus carpio var. koi
Kim, Yi-Oh ; Lee, Sang-Min ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 317~322
DOI : 10.5657/KFAS.2016.0317
This study was carried out to investigate the effects of various dietary lipid sources on the growth performance, body composition, and fatty acid profiles of juvenile fancy carp (Cyprinus carpio var. koi). Three replicate groups of fish (initial mean body weight, 15.1±0.18 g) were fed one of five experimental diets containing fish oil (SLO), soybean oil (SO), linseed oil (LO), lard (LA), or a mixture of SLO, SO, and LO (Mix) for 8 weeks. Fish fed the LA diet gained less weight than did fish fed the LO diet. The feed efficiency and protein efficiency ratio of fish fed the LA and Mix diets were lower than those of fish fed the SO and LO diets. The body lipid content of fish fed the SO diet was lower than those of the other groups. Whole-body fatty acid compositions reflected the fatty acid compositions of dietary lipid sources. Fish fed the SO diet had high concentrations of linoleic acid and arachidonic acid, whereas fish fed the LO diet were rich in linolenic acid. Fish fed the SLO diet had significantly higher levels of eicosapentaenoic acid and docosahexaenoic acid compared with fish fed the SO, LO, and LA diets. The results of this study suggest that SO or LO could be used as a replacement for SLO in the diets of juvenile fancy carp without any negative effects on growth and feed utilization when the dietary essential fatty acid requirements are satisfied for juvenile fancy carp.
Effects of Dietary Antioxidant Supplementation on the Growth, Serum Chemistry, Body Composition and Challenge Test Results of Juvenile Rockfish Sebastes schlegelii
Yun, Ahyeong ; Kim, Hee Sung ; Seo, Youngwan ; Cho, Sung Hwoan ; Bae, Jun Young ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 323~329
DOI : 10.5657/KFAS.2016.0323
The effects of dietary antioxidant [saltwort (SW), leek (LK), and dandelion (DD)] supplementation on the growth, body composition, serum chemistry, and challenge test results of juvenile rockfish, Sebastes schlegelii, were determined. In an experiment, 320 fish were randomly distributed into eight, 50-L flow-through tanks (40 fish per tank). Four experimental diets were prepared: the control diet (Con) with synthetic antioxidant: and diets with SW, LK, or DD from natural sources. Each diet was randomly assigned to duplicate tanks of fish, which were hand-fed to satiation twice daily for 8 weeks. After the 8-week feeding trial, 20 fish from each tank were artificially infected with Streptococcus iniae and monitored for 6 days. The dietary additives did not affect survival, weight gain, specific growth rate, feed efficiency (FE), protein efficiency ratio (PER), or plasma chemistry. However, the cumulative mortality of fish fed the SW, LK and DD diets was lower than that of fish fed the control diet beginning 4 days after infection. In conclusion, dietary supplementation with SW, LK, and DD did not affect the growth, FE, PER, or plasma chemistry of rockfish. However, dietary inclusion of SW, LK, and DD lowered the mortality of rockfish following infection with S. iniae.
Fecal Solid Feed from the Recirculating Aquaculture System of the Renewable Sea Cucumber Apostichopus japonicus
Jeong, U-Cheol ; Jin, Feng ; Choi, Jong-Kuk ; Md, Anisuzzaman ; Choi, Byeong-Dae ; Kang, Seok-Joong ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 330~336
DOI : 10.5657/KFAS.2016.0330
Pollution caused by fecal solids released from recirculating aquaculture systems (RAS) is a growing global concern requiring immediate attention. Thus, this study investigated the physicochemical characteristics of fecal solid feed from RASs used for eel and rainbow trout farming. The concentrations of proteins, lipids, crude ash, and moisture in eel fecal solids were 10.9%, 1.2%, 85.8%, and 72.2%, respectively, while those in rainbow trout fecal solid feed were 20.5%, 3.2%, 70.9%, and 87.0%, respectively. The control group was fed a mixture of sea cucumber and dried sea mud. The protein digestibilities of eel and rainbow trout fecal solids were 25.43% and 23.96%, respectively, while the respective lipid digestibilities were 35.62% and 36.80%, respectively.
Sea Cucumber Apostichopus japonicas Growth in Pond-bottom and Lantern-net Cultures
Jeong, U-Cheol ; Han, Jong-Cheol ; Kang, Seok-Joong ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 337~342
DOI : 10.5657/KFAS.2016.0337
Sea cucumbers have been an important part of human diets throughout history; demand is increasing every year, making the species a target for coastal resource development. New harvesting technologies have been developed in response to demand, including nursery production and insemination aquaculture, but such methods produce relatively few individuals and productivity per unit area is very small. For example, captures are prohibited during July and August due to the breeding season, and sea cucumbers aestivate during the hot season and hibernate during the cold season, all factors that limit natural-environment production in Korea. Problems with slow growth of sea cucumbers have been encountered in previous rearing experiments. To assess the importance of feeding ecology on sea cucumber growth, we conducted pond-bottom and lantern-net culture experiments. Results showed that sea cucumbers in bottom cultures grew from 3.06 to 102.59 g, but those in lantern cultures only grew from 25.60 to 28.03 g.
A Laboratory-scale Recirculating Aquaculture System for Sea Cucumber Apostichopus japonicus
Jeong, U-Cheol ; Jin, Feng ; Choi, Jong-Kuk ; Han, Jong-Cheol ; Choi, Byong-Dae ; Kang, Seok-Joong ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 343~350
DOI : 10.5657/KFAS.2016.0343
The sea cucumber Apostichopus japonicus is a commercially valuable aquaculture species in Korea. Aquaculture species require specific nursery culture conditions to increase survival and growth rates. Sea cucumbers hibernate during the high temperatures of summer and during the low temperatures of winter, and suboptimal temperature conditions decrease sea cucumber growth and survival rates. The natural South Korean environment is very unfavorable for culturing sea cucumber; therefore, developing a recirculating aquaculture system (RAS) capable of breeding and growing sea cucumber year-round is necessary. The aim of this study was to investigate growth performance of juvenile sea cucumber in a RAS. Growth and survival rates of juvenile sea cucumber were high during our 24-week experiment. Sea cucumber survival rates were 87.8-93.3%, and specific growth rates were 0.4689-0.7846.
Growth Performance of the Rotifer Brachionus plicatilus and the Larvae of Two Bivalves Fed on the Cryptophyte Teleaulax amphioxeia
Park, Hee Won ; Kim, Hyung Seop ; Jo, Soo-Gun ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 351~358
DOI : 10.5657/KFAS.2016.0351
The aim of this study was to verify the performance of Teleaulax amphioxeia as prey for Brachionus plicatilis and for the larvae of the bivalves (Pacific oyster Crassostrea gigas and Manila clam Ruditapes philippinarum) to select the best of five T. amphioxeia strains. The five strains of T. amphioxeia were collected from the coasts of Korea, purecultured and then fed to the rotifer and bivalve larvae. The density and fecundity rate of the rotifer fed on strain 01 were the highest. The instantaneous growth rate of the rotifer fed strain 08-2 was the highest. The maximum density and fecundity rate of the rotifer fed strain 08-2 were significantly higher than those fed Chlorella ellipsoidea, while instantaneous growth rate showed the opposite pattern. Survival rates of the Manila clam larvae fed each strain of Teleaulax showed no significant difference between strains. Survival rates of the Pacific oyster fed Teleaulax were significantly higher than those fed Chaetoceros sp., but lower than those fed I. galbana. This study indicates that strain 08-2 showed better growth for B. plicatilis and better survival for the bivalve larvae than did the other strains, and that T. amphioxeia can also be used as a prey organism for rotifers or bivalve larvae.
Biochemical and Molecular Characteristics of Vibrio anguillarum Isolated from Alaska Pollock Theragra chalcogramma Seedlings
Jeon, Chan-Hyeok ; Nam, U-Hwa ; Kim, Jeong-Ho ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 359~366
DOI : 10.5657/KFAS.2016.0359
The health of Alaska pollock Theragra chalcogramma seedlings was monitored during February and April 2015. After microscopic examination for parasites, 20 samples sets were made by pooling 50 individuals for each sample set. Then, they were homogenized and examined for viral and bacterial pathogens. No parasites or viruses were detected using either microscopy or PCR. Colonies suspected of belonging to the genus Vibrio were isolated from Tryptic Soya Agar and Thiosulfate Citrate Bile Salts Sucrose Agar plate incubations, and identified as Vibrio anguillarum based on biochemical and physiological examinations and PCR amplification of the 16S rDNA, recA, and pyrH genes. Although there was no mortality during the sampling period, 65.0% (13/20) of the pooled samples were PCR-positive for V. anguillarum. To prevent possible outbreaks, the pathogenic potential of V. anguillarum should be investigated in the future.
Maturity and Spawning of the Marbled Flounder Pseudopleuronectes yokohamae off the Coast of Pohang, East Sea
Kim, So Ra ; Cha, Hyung Kee ; Lee, Jae Bong ; Lee, Hae Won ; Yang, Jae Hyeong ; Baek, Hea Ja ; Kim, Sung Tae ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 367~375
DOI : 10.5657/KFAS.2016.0367
Marbled flounder Pseudopleuronectes yokohamae is a commercially important flatfish in the coastal waters of the East Sea off Pohang, Korea. Maturity and spawning dynamics of P. yokohamae were investigated based on samples collected by gill net and long line in the coastal waters off Pohang from January 2013 to December 2014. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length at 50% group maturity. We found that the spawning period was December to February, wherein fecundity ranged from 55,760 eggs at 20.40 cm total length (TL) to 1,559,007 eggs at 46.6 cm TL. The relationship between TL and fecundity (F) was F = 0.0017 TL
= 0.6984), and F increased with increasing TL. We estimated the TL at 50% group maturity as 27.4 cm for female and 23.5 cm for male P. yokohamae, respectively. The results from this research will aid in the development of policies on season and minimum catch length for sustainable production of P. yokohamae. We propose that it is necessary to conduct long-term ecological monitoring for this species because biological properties such as spawning ecology and growth performance are being affected by climate change.
Understanding the Migration Path of Spanish Mackerel Scomberomorus niphonius using Catch Distributions
Kim, Heeyong ; Lim, Yu Na ; Song, Se Hyun ; Kim, Yeong Hye ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 376~384
DOI : 10.5657/KFAS.2016.0376
Seasonal catch distributions of large purse seines and daily landings of coastal set nets were analyzed to understand the migration path of the Spanish mackerel Scomberomorus niphonius around Korean waters. The Spanish mackerel start to move toward the coastal region in the South and West Sea in May for spawning and stay until July, when spawning finishes. Afterwards, they start to migrate to the East China Sea and the southern East Sea and are found irrespective of the onshore and offshore regions. Therefore, they disappear from the offshore region during the spawning season in June and July, and a new recruitment population of age 0 begins to inflow into the coastal fishing grounds in the South Sea and West Sea in August, one month earlier than in the Japanese coastal region of the East Sea.
Ecological Evaluation of Marine National Parks Based on Seaweed Community Index
Oh, Ji Chul ; Choi, Han Gil ; Kim, Cheol Do ; Ahn, Jung Kwan ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 385~392
DOI : 10.5657/KFAS.2016.0385
Seasonal variability in the algal community structure of intertidal zones was examined at six study sites in Marine National Parks, on the western and southern coasts of Korea from March to November 2015. A total of 193 species of algae, comprising 27 green, 40 brown and 126 red algae, were identified. Algal biomass averaged 101.50 g dry wt./m
with a maximal at Tonggae (168.12 g dry wt./m
) and minimum at Haseom (54.49 g dry wt./m
). The dominant seaweeds by biomass were Sargassum thunbergii at five sites (Tonggae, Haseom, Namdongri, Ando amd Sinjeonri), and S. fusiforme at Soando. Community indices measured as follows: dominance index (DI), 0.31–0.69; richness index (R), 7.30–11.43; evenness index (J'), 0.33–0.49; and diversity index (H'), 1.15–1.86. As evaluated using community indices and environmental states, the EEI (Ecological Evaluation Index) of the Marine National Park was “normal”. The present results indicate that seaweed community structures and indices could be used to evaluate the environmental status of coastal ecosystems.
Observations of Bottom Currents in the Korea Strait
Lee, Jae Chul ; Kim, Dae Hyun ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 393~403
DOI : 10.5657/KFAS.2016.0393
A steady, strong southward flow was observed in the lower layer beneath the Tsushima Warm Current in the deepest trough of the Korea Strait. Known as the Korea Strait Bottom Cold Water (KSBCW), this bottom current had a mean velocity of 24 cm/s and temperatures below 8–10℃. The direction of the bottom current was highly stable due to the topographic effects of the elongated trough. To determine the path of the southward bottom current, ADCP (Acoustic Doppler Current Profiler) data from 14 stations between 1999 and 2005 were examined. Persistent southward flows with average speeds of 4–10 cm/s were observed at only three places to the north of the strait where the bottom depths were 100–124 m. The collected data suggest a possible course of the southward bottom current along the southeast Korean coast before entering the deep trough of the Strait.
Maturity and Spawning of Sebastes thompsoni in the Coastal Waters off Ulleungdo, Korea
Yang, Jae Hyeong ; Lee, Jae Bong ; Lee, Hae Won ; Cha, Hyung Kee ; Kim, So Ra ; Heo, Yo Won ;
Korean Journal of Fisheries and Aquatic Sciences, volume 49, issue 3, 2016, Pages 404~409
DOI : 10.5657/KFAS.2016.0403
We investigated the maturation and spawning of Sebastes thompsoni in the coastal waters off Ulleungdo, based on samples collected by gill net from March 2013 to February 2014. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length (TL) at 50% group maturity. The average TLs of female and male S. thompsoni were 22.6 cm and 22.5 cm, respectively. The main parturition period of females was during March and April. The GSI of females began to increase in January, and reached a maximum in March. The GSI of male reached a maximum between January and February. The spawning period of males was shorter than that of females. The egg diameter during gestation stage was 1.4±2.1 mm. The TL of females at 50% group maturity was 22.3 cm.