• 수산해양기술연구
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• 제28권4호
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• pp.327-336
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• 1992

In order to establish one of the forecasting model for the fishing conditions of squid angling fisheries in the Eastern Korea Sea, the catch data for the years of 1955~1991 and the water temperature data for the years of 1979~1990 were analysed, and then some parameters, that is, the water temperature normal year anomaly in the spawning and the rapidly growing season, the adult resource amount and etc were examined statistically correlation with the catch fluctuation of the main fishing seasons. From the result, authors suggested a formula as a forecasting model, Y=25785+1099X sub(1)+1074X sub(2)+6.033X sub(3)+3.95X sub(4)+1.330X sub(5)(M/T)(R super(2)=0.867, P<0.01) in the case that Y is the yearly catch, X sub(1) and X sub(2) are the water temperature normal year anomalies in October and December of the previous year and that in February and April, and X sub(3), X sub(4) and X sub(5) are the catches in October, in September, in November of previous year respectively. Because these parameters could be checked in earlier time of a half year before the main fishing season, this model was assumed to be very useful for the prediction of fishing conditions of squid angling fisheries.

• 수산해양기술연구
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• 제51권4호
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• pp.553-560
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• 2015

The feeding habits of the Pacific bluefin tuna, Thunnus orientalis were examined based on the stomach contents of 330 specimens caught by offshore large purse seine fishery in the southern sea of Korea, 2011. The size of Pacific bluefin tuna used in this study ranged from 34.1 to 67.3 cm in fork length (FL). The percentage of empty stomachs was 41.8%. The main prey items were Pisces and Cephalopoda based on percentage IRI (index of relative importance). The main fish preys were Trachurus japonicus, Bregmaceros japonicus, Engraulis japonicus, and Cephalopoda were Todarodes pacificus, Loligo edulis, Watasenia scintillans. T. orientalis showed ontogenetic change in diet composition. Although Pisces dominated the diet of all length classes the portion of Cephalopoda was relatively higher in size between 40 and 50 cm other than length classes. In terms of seasonal variation in feeding habits, Pisces was the main prey group in all seasons, but Cephalopoda was also frequently consumed during spring and autumn based on %IRI.

• 한국수산과학회지
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• 제44권5호
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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.

• 대한원격탐사학회지
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• 제36권1호
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• pp.41-53
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• 2020

The production of near- and off-shore fisheries in South Korea is decreasing due to rapid changes in the fishing environment, particularly including higher sea temperature in recent years. To improve the competitiveness of the fisheries, it is necessary to provide fish catch information that changes spatiotemporally according to the sea state. In this study, artificial intelligence models that predict the CPUE (catch per unit effort) of mackerel, anchovies, and squid (Todarodes pacificus), which are three major fish species in the near- and off-shore areas of South Korea, on a 15-km grid and daily basis were developed. The models were trained and validated using the sea surface temperature, rainfall, relative humidity, pressure,sea surface wind velocity, significant wave height, and salinity as input data, and the fish catch statistics of Suhyup (National Federation of Fisheries Cooperatives) as observed data. The 10-fold blind test results showed that the developed artificial intelligence models exhibited accuracy with a corresponding correlation coefficient of 0.86. It is expected that the fish catch models can be actually operated with high accuracy under various sea conditions if high-quality large-volume data are available.

• 수산해양기술연구
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• 제29권3호
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• pp.177-182
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• 1993

In order to estimate the mesh selectivity master curves and the optimum mesh size, experiments were made by the cover net method with the cod-ends of the five different the opening mesh sizes(51.2mm, 70.2mm, 77.6mm, 88.0mm and 111.3mm). After that 163 hauling were performed and there by investigated, on the training vessel Saebada in the Southern Korean Sea and East China Sea from June 1991 to August 1992. In this report, the mesh selectivity master curves were fitted by using logistic function(S=1/(1+exp super(-(aR+b))), R=(L-L sub(0))/(M-M sub(0)) and the optimum mesh sizes were estimated from each master curve. In this case, a and b are the selection parameters, M is the mesh size of each experimental cod-end. L is body length, L sub(0) and M sub(0) is the distance from the coordinate origine to intersection of linear regression between 25% and 50% selection length. The results obtained are summarized as follows; 1. Trachurus japonicus: Mesh selectivity master curve parameters: a and b were 2. 25, -4.73 respectively and optimum mesh size was estimated to be 79.3mm. 2. Trichiurus lepturus: Mesh selectivity master curve parameters: a and b were 0.81, -3.17 respectively and optimum mesh size was estimated to be 64.5mm. 3. Photololigo edulis: Mesh selectivity master curve parameters: a and b were 1.30m, -4.10 respectively and optimum mesh size was estimated to be 89.9mm. 4. Todarodes pacificus: Mesh selectivity master curve parameters: a and b were 1. 35, -3.45 respectively and optimum mesh size was estimated to be 89.4mm.

• 생명과학회지
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• 제14권2호
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• pp.221-224
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• 2004

일반적으로 오징어의 콜레스테롤 함량은 높다고 보고하고있지만, 이는 주요 가식부인 몸통육에 대한 것이고, 여타 스테롤도 함께 정량하는 비색법에 의한 정량 결과인 경우가 많아 신뢰하기 힘들다. 그리고 이런 단점을 개선한 효소법이나 GC법은 모두 다 또 다른 단점인 고가 효소 키트가 필요하다던가 복잡한 전처리가 필요하다던가 하여 적용하기가 쉽지 않다. 따라서, 오징어 몸통 이외의 새로운 가식부로 이용되고 있는 껍질부, 내장이나 간장부위 등에는 얼마만큼의 콜레스테롤이 함유되어 있는지 정량해 보고 아울러 기존 효소법이나 GC법의 단점을 모두 극복한 Iatroscan법에 의한 콜레스테롤 정량을 시도 확립해 보았다. 또한, 이 방법의 확립을 위해 필요한 오징어 부위별 수분함량과 지방함량 및 지방종 분석도 동시에 행하였다. 한국산 물오징어 중의 부위별 수분 및 지방함량에 있어서 간장부위가 각각 50.4%, 15%로서 다른 부위와 큰 차이를 보였고, 다른 부위는 각각 75.8∼83.6%, 1.9∼4.7% 수준으로서 큰 차이는 없었다. Iatroscan법에 의한 콜레스테롤 정량을 위한 근거가 되는 지방종 조성비에 있어서는 간장부위는 92.1%가 중성지방으로서 주성분을 이루고 있었고, 몸통육과 다리육이나 껍질부위는 인지질이 81.2∼87.9%%로서 주성분이었다. 5$\alpha$-cholestane을 내부표준물질로한 Iatroscan법에 의한 콜레스테롤 정량 결과 기존의 효소법과 GC법에 의한 수치와 큰 차이를 보이지는 않아 가장 간단히 콜레스테롤을 정량해 내는 법으로 사용할 수 있다고 판단되었다. 즉, Iatroscan법으로 오징어 부위별 콜레스테롤을 정량한 결과 오징어 간장 부위에 643.2 mg%, 껍질에 608.8 mg%, 다리육에 321.4 mg%, 눈 부위에 159.5 mg%, 주가식부인 몸통육에 178.9 mg% 수준으로 콜레스테롤이 함유되어 있었다.

• 수산해양기술연구
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• 제50권3호
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• pp.326-333
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• 2014

This study was conducted to investigate the fishing efficiency of an improved LED fishing lamp for squids. A total of 31 fishing operations were carried out with six-crew commercial fishing vessel Haengbok-Ho (24 tons) on which 43.2kW LED was installed, along with 14 automatic jigging machines, from October 6 to November 16, 2012. The 19 fishing vessels with Haengbok-Ho were compared with a control subject was 24 tons or 29 tons. A total illuminating power of metal halide (MH) fishing lamps in the control fishing vessel was either 84kW or 120kW. The number of automatic jigging machines in the control vessels was 8-18 and the number of crews engaged for fishing operation was 3-13. Average fuel consumption of LED fishing vessels during fishing operation was 505.1l which led to an average fuel consumption of 42.7l per hour. LED fishing vessel and MH fishing vessel caught on an average 1,946 squids and 2,439 squids, respectively, during the study period. Crews (hand line and hand reel) caught about 2.2 times the automatic jigging machines for LED fishing vessel and about 2.1 times for MH fishing vessel. Meanwhile, catches by the fishing vessels with LED in the combined total number per one line of automatic jigging machine and per crew were 86.6% of that of the control fishing vessel with MH. Also, fishing vessels with LED per automatic jigging machine achieved 71.8% of catches of that with MH fishing lamp. The catches of squids per the fishing vessel with 1W LED fishing lamp were higher by more than 135.5% of that in the fishing vessel with MH, which showed a good fishing performance even with only the use of a LED fishing lamp.

• 한국수산과학회지
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• 제55권5호
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• pp.625-637
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• 2022

The southern coast of the East Sea is an important area affected by large warm currents as it connects the coastal waters of Jeju Island, the South Sea, and Dokdo. From 2017 to 2021, the average catch per unit effort (CPUE; kg/day/ship) of set net fishery at six ports in the Gyeongbuk region off the southern coast of the East Sea was the highest in Gampo, Gyeongju, and the lowest in Hupo, Uljin. Although the seasonal variation in the CPUE differed by region and year, it was generally high in autumn. In the set net fishery in Pohang from 2019 to 2021, we identified 72 species, which decreased to 56 species in 2019, 46 in 2020, and 41 in 2021. The species diversity index slightly increased over the three-year periods. We found positive correlations between the total catch (kg) of subtropical species in autumn and the water temperature at 50 m. Among the most abundant species, we found substantially positive correlations between the CPUE of Scomber japonicus, Scomberomous spp. and Carangids. We also noted positive correlations between the CPUE of Todarodes pacificus, Seriola spp. and Carangids.

• 한국수산과학회지
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• 제27권3호
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• pp.223-231
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• 1994

오징어 식해 개발을 위하여 식해 숙성시 숙성온도 및 기간에 따른 TBA, fatty acids, free amino acids 및 미생물의 변화와 단백질 분해효소의 정제 실험을 요약하면 다음과 같다. TBA 값은 각 온도에서 숙성 5일만에 최고치를 나타내었다가 감소하였으며 숙성온도 $10^{\circ}C$에서 지질의 산화가 가장 많았다. 오징어 식해의 지방산 조성은 linoleic acid(18:2), oleic acid(18:1)가 $60\%$ 이상 점유하였으며 EPA(20:5) 및 linilenic acid(18:3)은 약 $13\%$ 정도였다. 숙성기간이 길어질수록 linolenic acid 및 EPA는 현저하게 분해되었으며 $10^{\circ}C$ 및 $15^{\circ}C$에서 지방산화가 촉진되었다. 식해의 유리 아미노산 조성 은 Pro, His, Arg, Leu, Glu 등이 높은 점유율을 나타내고 있으며 숙성기간이 증가할수록 Ser, His, Arg 등은 점유율이 낮아지며, 반면에 Glu, Ala, Val, Tyr 등은 높아졌다. 그리고 숙성온도가 증가할 수록 Glu, Val 및 Met은 점유율이 증가하였으며 Ala, Cys, Thr 및 Gly은 감소하였다. 미생물의 변화는 총균수는 온도가 높을수록 증가하였으며 숙성 10일만에 최대로 되었다가 그 후 감소하였다. Lactic acid bacteria 수는 각 숙성온도에서 숙성 15일째에 최대였다가 그후 감소하였으며 숙성온도가 높을 수록 증가속도 및 감소속도도 빨랐다. Proteolytic bacteria 수는 숙성온도가 높을수록 증가량 및 속도가 빨랐으며 숙성기간이 증가함에 따라 감소량도 많았다. Psychrotrophs수는 $10^{\circ}C$ 숙성에서 제일 높았으며 숙성기간 15일째가 최대였다. 단백질분해능이 강한 균주들을 동정하였을 때 모두 Bacillus 속으로 밝혀졌다. 단백질 분해효소는 ammonium sulfate $60{\sim}80\%$ 농도 사이에서 최대로 추출되었으며 이온교환수지로 정제하였을 때 3개의 peak중 마지막 peak에서 활성을 나타내었으며 전기영동 결과 분자량이 대략 $20,000{\sim}40,000$사이에 15개 정도의 bands가 나타났다.

• 한국식품위생안전성학회지
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• 제30권1호
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• pp.43-50
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• 2015

본 연구에서는 오징어류에 해당하는 대왕오징어, 오징어, 문어, 한치 및 이를 이용한 가공식품에 대해서 분자생물학적 기법을 활용한 시험법을 검토하였다. 시료 중 원료성분 확인을 위하여 오징어류 4종에 대해 최적의 종 특이 프라이머를 디자인하였으며, 시료로부터 직접 genomic DNA를 추출하여 PCR을 실시하였다. PCR 수행과정에서 반응을 저해하는 염 성분을 제거하기 위하여 증류수를 이용하여 3~4회 세척 후 PCR을 실시한 결과, Single PCR의 경우 대왕오징어(552 bp), 오징어(463 bp), 문어(247 bp), 한치(354 bp)에 해당하는 종 특이적인 증폭산물을 확인하였으며, Multiplex PCR 의 경우 서로 다른 종 사이의 교차반응없이 동시다발적으로 증폭이 일어남을 확인할 수 있었다. 또한 이들 4종에 대해 PCR 민감도를 조사한 결과, 모두 약 $0.1ng/{\mu}l$의 농도까지 검출이 가능함을 확인하였으며 multiplex PCR의 경우 약 $0.25ng/{\mu}l$의 농도까지 검출이 가능함을 확인하였다. 이를 이용하여 오징어류가 함유된 수산물 가공식품 8건에 대해 적용성을 검토한 결과, 모든 시료에서 유효한 결과를 확인할 수 있었다. 따라서 본 연구에서 제작된 오징어류 4종에 대한 종 특이적 프라이머는 생물 상태뿐만 아니라 수산물 가공식품에 대해서도 이를 판별할 수 있어 식품안전관리에 활용할 수 있을 것으로 기대된다.