• 한국환경과학회지
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• 제26권2호
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• pp.173-181
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• 2017

Catch data for the common squid (Todarodes pacificus), classified by squid-jigging fisheries per grid (size: $0.5^{\circ}latitude{\times}0.5^{\circ}longitude$), and the water temperature values KODC (Korea Ocean Data Center) were collected for the 1980-2009 period to study the changes in squid distribution and migration with climate regimes (1980s, 1990s, and 2000s). The primary fishing period in the 1990s and 2000s was approximately 2-3 months earlier than that in the 1980s. Especially in the East Sea, the fishing grounds in the 1980s stayed longer at high latitudes than those in the other decades. Moreover, in the 1980s, centers of the fishing ground were located near the Yamato bank (central East Sea), whereas in the 1990s and 2000s, they were situated near the southeastern coast of the Korean peninsula.

• 한국수산과학회지
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• 제31권1호
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• pp.26-30
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• 1998

본 연구는 1991년 2월부터 1992년 7월까지 한국 해역에 분포하는 오징어의 위내용물을 분석한 것이다. 위내용물의 종류를 살펴보면, 해조류, 갑각류, 두족류, 어류 외 동정 불가능한 것도 나타났다. 먹이생물중 어류를 가장 많이 먹었으며, 그 다음으로 두족류, 갑각류, 해조류 순으로 섭이하는 것으로 나타났다. 위의 만복도 조성에서 공위가 $58.00\%$이었고, 만복된 위는 $6.37\%$이었다. 여름과 가을 계군은 어류를 가장 많이 섭이한 반면, 겨울계군은 두족류를 매우 우점적으로 섭이하였다. 해조류와 갑각류는 세 계군 모두 매우 적은 양이 섭이되었다. 오징어의 주요 먹이생물은 어류이었고, 계군에 따른 위내용물의 차이는 없었다.

• Ocean and Polar Research
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• 제37권4호
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• pp.357-368
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• 2015

This study analyzed structural changes and asymmetry of price volatility during the period before and after a point of structural change in price volatility, using the Korean fresh common squid daily retail price data from January 1, 2004 to September 30, 2015. This study utilized the following analytical methods: the unit-root test was applied to ensure the stability of the data, the Quandt-Andrews breakpoint test was applied to find the point of structural change, and the Glosten-Jagannathan-Runkle GARCH and EGARCH models were applied to investigate the asymmetry of price volatility. The empirical results of this study are as follows. First, ADF, PP, KPSS and Zivot-Andrews tests showed that the daily retail price change rate of the Korean fresh common squid differentiated by logarithm was stable. Secondly, the ARIMA (2,1,2) model was selected by information criteria such as AIC, SC, and HQ. Thirdly, the Quandt-Andrews breakpoint test found that a single structural change in price volatility occurred on June 11, 2009. Fourthly, the Glosten-Jagannathan-Runkle GARCH and EGARCH models showed that estimates of coefficients within the models were statistically significant before and after structural change and also that asymmetry as a leverage effect existed before and after structural change.

• 수산해양기술연구
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• 제47권3호
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• pp.183-193
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• 2011

This study made a comparative analysis of behavioral reaction of squid to red (624nm), green (524nm), blue (460nm) & white LED light, its arrival time for the shadow section by making the shadow section in the central section of a water tank just like the bottom part of a squid jigging vessel, and on-site catching efficiency of LED fishing lamp with control fishing vessel. The color LED light showing the highest squidgathering rate as against the shadow section was found to be blue LED light with 39.3% rate under the dark (0.05lx) condition. Under the brighter condition than 0.05lx, white LED light was found to have the highest gathering rate of 41.5%. In addition, it was found that squid gathering rate was high at the shadow section which showed 6.3-fold brightness difference between the shadow section and bright section. As for the arrival time for the shadow section, blue LED light was found to be the fastest in attracting squids in 192.7 seconds under the dark condition while the red LED light was the fastest in luring squids in 164.6 seconds under the bright condition. The ratio of the squid-jigging operation and sailing in fuel consumption of the fishing vessel loaded with LED fishing lamp is about 7 to 1, showing most of the fuel is consumed more in sailing than in squid-jigging operation. As for a catch of squid, the control vessel loaded with MH (Metal Halide) fishing lamp had more catch of 600-7,080 squids than the vessel loaded with LED fishing lamp having a catch of 260-1,700 squids. In addition, even in the comparison of a catch per automatic jigging machine, the catch of the vessel loaded with MH fishing lamp excelled that of the vessel loaded with LED fishing lamp in 6 operations of squid jigging out of 9 operations. The ratio of hand-jigging and automatic jigging machine (one line) in the LED fishing lamp vessel was 1:1.1 excepting the case of having a catch only using an automatic jigging machine, showing almost the same with each other in catches, while in case of a MH fishing lamp vessel, its ratio against hand-jigging was 1 to 5.8, showing hand-jigging excelled in catches.

• 한국환경과학회지
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• 제22권10호
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• pp.1363-1371
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• 2013

In this study, we estimate the interannual spatial and temporal distributions of fishing grounds at night in the East Sea based on satellite and in-situ data. We observe that the $15^{\circ}C$ thermal front moves in the north-south direction according to the movement of the warm water (above $18^{\circ}C$) in the Tsushima Warm Current (TWC) area, forcing the cold water area (below $10^{\circ}C$) to either expand or shrink. The interannual variations of sea surface temperature (SST) in winter represented by the indicator SST of $6^{\circ}C$ are consistent with the east-west zonal areas in the central East Sea which represented over $1^{\circ}C$ standard deviation of SST in February during 1990-2000. Annual SST in the fishing grounds of common squid fishing vessels, observed both by fishing vessels and satellites range from 9-$22^{\circ}C$, with the satellite-observed data having a larger range than the fishing vessel-based ones. The interannual distributions of the common squid fishing grounds in the East Sea are mostly concentrated in the TWC area in the southwestern part of the East Sea and in the coast of southern Honshu and Hokkaido in Japan. The interannual distributions of the nighttime fishing vessels are consistent with the catches investigated from the fishing vessel.

• 한국수산과학회지
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• 제37권4호
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• pp.345-353
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• 2004

Target strength (TS) of Japanese common squids (Todarodes pacificus) were measured using 38 and 120 kHz split beam scientific echosounders under the live condition. For the TS measurement of an individual, a total of 3 squids (mantle length (ML): 22.8, 25, and 27 cm) were used using small fishhook method, whereas for measurement of swimming angle, a total of 8 squids (ML: 21-27 cm) were used under live condition, confined with net cage with 2 m diameter At the same time, two underwater video cameras enabled continuous monitoring of squid behavior. Considering normal behavior, the mean TS at 38 and 120 kHz varied from -48.6 to -45.9 dB, and from -46.5 to -44.6 dB, respectively In both frequencies, mean TS at 120 kHz is relatively higher than that of 38 kHz, approximately 1.3-2.5 dB. From free living condition, the mean swimming angle of the squlds was $-24^{\circ}$. The results of the measurement will be provided basic information for conducting acoustic surveys of the squid.

• 한국수산과학회지
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• 제54권5호
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• pp.724-732
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• 2021

This study used response surface methodology to investigate the optimal conditions to reduce the bitterness of alcalase-treated anchovy hydrolysate (AAH) by the aminopeptidase active fraction (AAF) derived from the common squid Todarodes pacificus hepatopancreas. The central composite design selected AAF/AAH ratio (X₁, %) and hydrolysis time (X₂, h) as independent variables, and the degree of hydrolysis (Y₁) and bitterness (Y₂) as dependent variables. The uncoded values of the multiple response optimization for independent variables were 3.4% for the AAF/AAH ratio and 9.2 h for the hydrolysis time. The predicted values of the yield and bitterness score of alcalase-AAF continuously treated anchovy hydrolysate (AAAH) under the optimized conditions were 68.9% and 4.6 points, respectively. Their measured values of 69.5% for yield and 4.6±0.5 points for bitterness were similar to the predicted values. The food components of AAAH were 91.4% (moisture), 7.5% (protein), 0.1% (lipid) and 0.6% (ash). The findings indicate the potential value for use as an anchovy seasoning base. The results also confirm that the bitterness of AAH was remarkably improved by AAF and implicates AAF derived from squid hepatopancreas as a good enzyme to catalyze reduced bitterness.

• 한국임상수의학회지
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• 제32권3호
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• pp.239-242
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• 2015

오징어에 기생하는 Nybelinia surmenicola의 충미충 감염상을 조사하고 광학 및 주사전자현미경을 적용하여 종을 동정 하였다. 대전 어물전에서 시판하는 총 200 마리의 오징어를 검사하여 54 마리 (27%)에서 N. surmenicola의 충미충을 검출하였다. 양성 오징어의 충미충 출현빈도는 2.28이였다. 충체의 길이와 폭은 $6.1-11.1(8.05){\times}2.0-2.2(2.1)mm$이였고 흡구는 $2.4-2.8{\times}0.62-0.69(2.65{\times}0.64)mm$로 계측되었다. 문 (tentacule)은 돌출되어 있으며 사선으로 16개의 갈고리가 무장되어 있었다. 문초(tentacle sheaths)는 bulb 가까이에서 1회 꼬여 있었다. 흡구 가장자리에 사상의 microtriches가 존재하였다. 4개의 거대한 흡구는 가장자리에서 사상모양의 microtriches에 의해 분리되었다. 본 논문은 한반도 연안 오징어에서 N. surmenicola 충미충 검출의 최초 보고이다.

• 한국수산과학회지
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• 제39권5호
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• pp.376-383
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• 2006

The chemical components, lipid class, and fatty acid composition of the viscera from male and female common squid, Todarodes pacificus, were examined to evaluate the possible utilization of the liver, reproductive organs, and gills. In male and female squid, the viscera comprise 21% and 27% of the body weight, respectively. The protein content of the viscera was slightly higher in females (17.7-19.5%) than in males (15.6-17.2%). This was especially marked in the female reproductive organs, while there was little difference in the gill. The liver contained the largest amounts of lipids (17.2-18.6%) and the levels were higher in males than in females (P<0.01). By contrast, the reproductive organs of females contained more lipids than did those of males (4.68% vs. 1.65%, p<0.01). The prominent non-polar lipid (NL) classes were triacylglycerol (51.9-55.4% of the NL content) and sterol ester (16.3-21.8%) in the liver, and free sterol (47.0-68.5%) and free fatty acids (31.5-41.2%) in the reproductive organs. However, there were no significant differences in the NL classes between sexes. The percentage of the most prominent phospholipid (PL) class, phosphatidylcholine (PC), was highest in the liver (78.1-79.6% of the PL content), and there was no significant difference between the sexes. By contrast, phosphatidylethanolamine (PE) was highest in the reproductive organs (33.4%), and was higher in males than in females (P<0.05). All the visceral organs contained 36.4-48.5% of n-3 polyunsaturated fatty acids (PUFA), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The DHA level was highest in female reproductive organs (32.3%), while EPA was high in male reproductive organs. These results demonstrate that the viscera of male and female common squid are a good source of DHA and EPA.

• 해양환경안전학회지
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• 제10권1호
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• pp.61-67
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• 2004

본 연구에서는 동해의 오징어 어획량이 급증한 최근 $1990{\sim}1999$년 기간에 주목하여 동해에서의 오징어 어황 변동과 해황과의 관계를 조사하였다. 동해에서 오징어 어획량의 경년변화 특징은 1970년대부터 1980년대 초반에 감소하고 1980년대 후반에 증가하였다. 이것은 기후변화에 따른 regime shifts의 변동과 관계하는 것으로 나타났다. 월평균 어획량은 9-12월까지 풍어기, 3-5월 사이가 흉어기를 보이고, 최대 어획량은 10월에, 최소어획량은 4월에 나타났다. 해구별 안정 어장의 지표로 제시한 변동계수 (coefficient of variation) 값이 1.0 이하로 매년 안정된 어장은 구릉포 연안역과 울릉도 주변해역에서 형성되었다. 또한, 오징어의 최대 어획적수온 $16^{\circ}C$를 기준으로 한 어획적수심은 해역이 북상함에 따라 얕아졌다. 이 결과로부터 해역에 따라 조업시의 어획적수심에 대한 차등성을 둘 필요가 있음이 시사되었다. 또한, 조업 어장과 수온의 관계는 흉어기인 4월에 $10{\sim}14^{\circ}C$이고, 풍어기인 10월에 $10{\sim}20^{\circ}C$의 범위로서 오징어 어장 형성은 계절에 따른 대마난류역의 확장과 밀접하게 관련된 것으로 생각된다.