• 수산해양교육연구
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• 제7권2호
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• pp.182-200
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• 1995

1991년 1월부터 12월까지에 32척의 한국 다랑어 선망어선이 서부 태평양에서 가다랭이와 황다랑어 이를 주대상으로 조업하였다. 그 중에서 본 연구의 대상인 어선은 14척이었으며, 이들이 1년간에 조업한 매일의 조업선 누계는 4,153척, 총투망회수는 2,982회, 총어획량은 106,300M/T이었다. 이들이 어획한 어종별 어획량, 어체 크기별 어획량, 표면 수온별 어획량 분포를 고찰하고, 월별로 어획된 해역을 경위도 30'간격의 소해구로 분할하여 그 해구별 어획량 분포를 고찰한 결과를 요약하면 다음과 같다. 1. 어종별 어획량 비율은 가다랭이가 75.0%, 황다랑어가 22.3%, 눈다랑어 등 기타의 다랑어 및 새치류가 2.7%였다. 2. 가다랭이의 크기별 어획량은 개체의 중량 2.0~2.9kg의 것이 혼획된 경우가 68.0%로 가장 많았고, 1.5~1.9kg의 것이 혼획된 경우는 11.6%, 3.0~3.9kg의 것이 혼획된 경우는 9.9%였다. 황다랑어의 크기별 어획량은 5~9kg의 것이 혼획된 것과 10~19kg의 것이 혼획된 경우가 각각 23.1%, 28.3%로 많았고, 20~29kg의 것이 혼획된 경우는 15.8%, 30~50kg의 것이 12.5%, 2~50kg의 것이 9.7%였다. 3. 표면 수온별 어획량 분포는 $29.0^{\circ}C{\sim}29.4^{\circ}C$에서 전체 어획량의 49%가 어획되었고, $29.5^{\circ}C{\sim}29.9^{\circ}C$에서도 37%가 어획되었으며, $30.0^{\circ}C{\sim}30.4^{\circ}C$와 $28.5^{\circ}C{\sim}28.9^{\circ}C$에서는 6% 내외의 어획량에 불과했고, $28.4^{\circ}C$ 이하와 $30.5^{\circ}C$ 이상에서는 1%내외로 극히 부진하였다. 4. 월별, 해역별 어획량 분포를 보면, 가다랭이는 8월과 9월에 남위 $3^{\circ}{\sim}6^{\circ}$, 동경 $176^{\circ}$~서경$176^{\circ}$의 해역에서 각각 10,618M/T, 10,412M/T으로 가장 많이 어획되었고, 6월과 1월에 남위 $1^{\circ}$~북위$3^{\circ}$, 동경 $142^{\circ}{\sim}151^{\circ}$의 해역에서도 각각 8,824 M/T, 8,057M/T으로 많이 어획되었으며, 5월과 11월, 12월의 New GUINEA 연안 해역에서는 극히 부진하였다. 황다랑어 는 6월에 북위 $0^{\circ}{\sim}4^{\circ}$, 동경 $142^{\circ}{\sim}151^{\circ}$의 해역에서 4,070M/T으로 가장 많이 어획되었고, 2~4월과 10~12월의 연안 해역 및 도서 주변에서도 2천 M/T이상으로 많이 어획되었으나, 8~9월의 원양 해역에서는 극히 부진하였다.

• 수산해양기술연구
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• 제15권2호
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• pp.95-100
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• 1979

권현망에서는 어획물을 손상시키지 않도록 양망해야 하는데, 재래식에서는 순전히 인력으로서 양망하므로 30-34명이나 되는 인원이 필요하다. 이것을 성력화하기 위하여, 자루그물의 옆판쪽에 속으로 반달코가 있는 힘줄을 6가닥씩 넣고, 배에는 선미에 데릭부움을 설치하여, 거기에 장치된 블록줄끝의 훅을 반달코에 걸어서 사이드 드럼으로 감아 재래식처럼 자루그물을 까뒤집으면서 양망한 바, (1) 어획물이 손상되지 않고, (2) 사이드 드럼의 권양장력은 30명의 선원의 그것보다 크며, (3) 본래식의 반이하인 14명의 선원으로서 조업이 가능하고, (4) 자루그물의 양망 소요시간은 어획량이 많을수록 재래식보다 적게 소요된다는 사실이 규명되었다.

• 수산해양기술연구
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• 제42권4호
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• pp.203-209
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• 2006

This paper described the experimental squid jigging fishery conducted by a commercial fishing vessel in the Northwest Atlantic Ocean from August to October 2005. Author carried out experimental jiggings of 65 times during 57 days by three type of jigs which were pick jig, soft jig and soft luminous jig. The total catch, effort/day and catches/line-day of northern shortfin squid (Illex illecebrosus) were 12,726kg, 35 auto jigging machine and 3.5kg, respectively. Higher CUPE was observed in September, August and October. Catch ratio of pick jig was higher by 57-86% than those of soft jig and soft luminous jig. Higher catch was recorded at the $42^{\circ}55'N,\;62^{\circ}10'W$ with surface temperature ranging $18-21^{\circ}C$. The range of the dorsal mantle length was from 13.5cm to 23.0cm with average 17.2cm for female and from 13.0cm to 20.0cm with average 17.0cm for male. Sex ratio showed 55.4% of female.

• 한국수산과학회지
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• 제38권1호
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• pp.70-77
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• 2005

This paper studied the feasibility for utilization of the automatic fishing information recording system, which stores and manages navigational information and fish catch results of a fishing vessel in a portable storing device, in order to help promote the systematic management of fishing information by offshore and coastal fishing vessels. Position accuracy was within 10 meters on the position accuracy experiment using GPS module. Characteristics of navigation according to the navigation, anchoring and fishing operation showed the difference of navigation track information for GPS, and fishing possibility of fishing boat could be estimated through the analysis as the utilization result of system for the large pair trawl and large purse seiners. In particular, it is impossible to provide false positional information by arbitrarily operating the system, and it may be possible to present the factual results of fish catch by date, fishing ground, and fish species by comparing the fishing information with fish catch. Such contents are considered to be useful as basic data for the management of fisheries resources.

• 수산해양기술연구
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• 제52권3호
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• pp.197-208
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• 2016

The WCPFC CMMs related to tropical tunas have been strongly restricting fishing capacity and operating activities of main fisheries, especially purse seine fishery. In terms of changes in fishing trend by implementing relevant measures of FAD set, the number of FAD set by Korean purse seine fleet showed a decreasing pattern with the lowest level of FAD set proportion among major distant water fishing nations. With regards to the FAD closure, there was no significant change in fishing effort but a drop in catch, especially bigeye tuna during the period of FAD closure. Moreover, it showed closely similar trends between the number of FAD set and bigeye tuna catch. In terms of measures related to the high sea area including a ban on fishing on the HSP and limitation of fishing days on the high sea by flag state, proportions of catch and effort on the high sea had sharply declined after implementing those measures. As relevant measures are expected to be strengthened, it should pay attention to change of coastal nations policies and focus on improving fishing efficiency of unassociated school set with multi-pronged efforts.

• 한국수산과학회지
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• 제41권2호
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• pp.107-112
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• 2008

To evaluate uncertainty and risk in biological reference points, we applied a bootstrapping method and a Bayesian procedure to estimate the related confidence intervals. Here we provide an example of the maximum sustainable yield (MSY) of turban shell, Batillus cornutus, estimated by the Schaefer and Fox models. Fitting the time series of catch and effort from 1968 to 2006 showed that the Fox model performs better than the Schaefer model. The estimated MSY and its bootstrap percentile confidence interval (CI) at ${\alpha}=0.05$ were 1,680 (1,420-1,950) tons for the Fox model and 2,170 (1,860-2,500) tons for the Schaefer model. The CIs estimated by the Bayesian approach gave similar ranges: 1,710 (1,450-2,000) tons for the Fox model and 2,230 (1,760-2,930) tons for the Schaefer model. Because uncertainty in effort and catch data is believed to be greater for earlier years, we evaluated the influence of sequentially excluding old data points by varying the first year of the time series from 1968 to 1992 to run 'backward' bootstrap resampling. The results showed that the means and upper 2.5% confidence limit (CL) of MSY varied greatly depending on the first year chosen whereas the lower 2.5% CL was robust against the arbitrary selection of data, especially for the Schaefer model. We demonstrated that the bootstrap and Bayesian approach could be useful in precautionary fisheries management, and we advise that the lower 2.5% CL derived by the Fox model is robust and a better biological reference point for the turban shells of Jeju Island.

• 한국수산과학회지
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• 제53권1호
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• pp.57-66
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• 2020

The purpose of this study was to provide information about annual variations in catch size and changes in reproductive biology in the common octopus Octopus vulgaris, a commercially important species. Samples were collected from coastal waters off Gyeongnam, Korea, by coastal trap and coastal complex fishery from February to December 2018. Octopus vulgaris have been decreasing in this region since 2007 and catch prices have been increasing. The mantle length (ML) of O. vulgaris ranged from 1.2 to 21.2 cm and body weight ranged from 42.6 to 5,537 g. The sex ratio differed significantly from what was expected, at 0.45:0.55 (P<0.05). Mature females were found from February to December, except in October and November, and males occurred from February to December, except in October. The gonadosomatic index value was higher from May to September than in other months. The total number of eggs in fecund individuals ranged from 40,280 in 578.1 g of body weight to 138,994 in 1,666.5 g of body weight. The relationship between body weight and fecundity was F=76.486BW^1.0087 (r²=0.7897). At 50% group maturity, average weight was estimated to be 636.35 g, while it was 969.30 g at 75% maturity and 1736.55 g at 97.5% maturity. This study highlights changes in catch size and reproductive biology between 2007 and 2018. These results provide basic evidence that may be used to establish regulatory policy for O. vulgaris fisheries.

• 한국수산과학회지
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• 제16권4호
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• pp.341-348
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• 1983

한국 근해에서 최근 14개년간(1969-1982)의 멸치 자망에 의한 어획통계자료로부터 어장의 평균 분포와 해황과의 관계를 조사한 결과는 다음과 같다. 멸치의 중요어장은 어획이 있었던 전 어장면적의 $20\%$에 지나지에 지나지 않은 속초, 구룡포, 기장, 거제도, 및 충무의 인접한 5개 해구에 집중되어 있고, 연평균어획양의 약 $80\%$가 여기서 어획된다. 이 어장에서의 어획양 변동계수는 $0.3{\sim}0.6$으로서 작고, 평균 CPUE가 81.2 kg/set로 비교적 크다. 멸치 자망의 주어기는 일년 중 어획양이 극대치를 나타내는 $4{\sim}6$월의 춘계어기와 $10{\sim}11$월의 추계어기였다. 어장중심은 $37^{\circ}N$ 이북 해역에서는 주문진 동방 약10마일 역이며, $35^{\circ}-37^{\circ}N$ 해역에서는 기장 동방 약 25마일 역에 위치하고, $35^{\circ}N$ 이남 해역에서는 충무 남방 약 35마일 역이다. 일년중 어획양의 변동은 2월에 최소이고 5월에 최대인데, 이것은 냉수역 한계수온으로 생각되는 $10^{\circ}C$등온선과 관계가 깊었으며, $34.0{\sim}34.4\%0$ 등염선역이 주어장이 형성되는 곳이었으나 명확한 관계는 알수 없었다.

• 수산해양기술연구
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• 제47권4호
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• pp.290-299
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• 2011

Field tests were carried out with five different mesh sizes (86.6, 101.0, 121.2, 137.7, 151.5mm) to study the relative efficiency of monofilament and multifilament gill net for Marbled sole, Pleuronectes yokohamae, in the western sea of Korea, 2007-2009. The relative efficiency was analyzed by length distribution, catch in number, catch in weight and weight per individual for Marbled sole. Statistical T-test was done to verify the efficiency between two gears. In the field tests, the total body length range, catch in number and weight of Marbled sole was 15.8-48.2cm, 728 and 254,939g, respectively. During the field tests, Marbled sole less than 15cm length which is prohibition size of fishing was not caught, but the caught number of Marbled sole less than 19.5cm length which is first maturity length was 13 (1.8%) and the caught number of Marbled sole more than 19.5cm was 715 (98.2%). Catches of monofilament gill net was average 1.4 times more efficient than multifilament gill net. The weight per individual and total length by mesh sizes in the two gears tended to gradually increase according to mesh size increasing. But there was little difference of weight per individual and total length by mesh sizes between two gears.

• 수산해양기술연구
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• 제40권3호
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• pp.182-188
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• 2004

홑자망과 삼중자망에 의한 어획성능을 파악하기 위하여 한국 남해안의 거문도연안에 시설된 세라믹 어초어장에서 어구 성능시험과 수중 비디오 카메라로 어군 위집상을 조사로 하였다. 흩자망에 의한 폭당 어획량은 삼중자망에 비해 49.2% 많았으나, 어종수는 34.5% 적었는데, 이를 ANOVA로 분석한 결과 5% 유의수준에서 차이가 없었다. 어구별 우점종은 홑자망에서 참돔 1종, 삼중자망에서 참돔, 말쥐치, 홍어 등 3종이었으며, 홑자망에의해 어획된 참돔의 체장범위와 평균체장은 삼중자망에 어획된 참돔보다 다소 적게 나타났다. 홑자망에 의한 어획성능이 삼중자망보다 높았던 원인은 홑자망에 어획되기 쉬운 어종이 군을 형성하고 있었고, 개체의 크기도 홑자망에 적합하였기 때문이라고 판단된다.