• 수산해양교육연구
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• 제10권2호
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• pp.211-225
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• 1998

제주도 북제주군 구좌읍 동복리 연안에 설지된 정치망 어장의 각망어구 입구에 수중 비디오 카메라를 설치하여 입구로부터 입망하는 어군의 입망시간 및 입 출망행동과 어군의 유영속도, 그리고 어장주변의 유향, 유속을 조사한 결과를 요약하면 다음과 같다. 1. 자리돔, 날지, 전갱이, 고등어, 숭어어군은 07시부터 14시 사이에 입망되는 것을 확인하였다. 2. 어군의 입망시간과 조석과의 관계는 자리돔은 조류가 약한 전류시이고, 전갱이는 고조시와 저조시 중간의 조류가 빠른 낙조시에 주로 입망하는 경향이었다. 3. 각망에 입망한 어종별 어군의 출망비율은 숭어가 100%로 가장 컸으며 다음이 고등어 50%, 날치 45%, 자리돔 13%, 전갱이 0% 순이었다. 4. 어류의 유영속도는 자리돔 5~25cm/sec범위로서, 10~15cm/sec가 55%, 날치 20~5Ocm/sec의 범위로서, 30~35cm/sec가 30%, 전갱이 15~45cm/sec의 범위로서, 30~40cm/sec범위가 60%, 고등어 10~30cm/sec의 범위로서, 15~20cm/sec가 60%로서 가장 많은 비율을 나타냈다.

• 수산해양기술연구
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• 제32권1호
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• pp.50-58
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• 1996

The authors carried out a field experiment to confirm the effect of underwater sound on the luring of fish schools in a setnet in the coast of Cheju Island. The effects of the acoustic emission on the luring of fish schools were observed using a manufectured underwater speaker in the setnet, and pure sound, of which frequency was 600Hz and the source level was 126dB, was emitted on and off at 5 minutes intervals in the set net during the night of ,July 29 and ,July 31. So we had recorded behavior of fish schools by the telesounder with two channel and shape of the setnet by underwater video camera and analyzed them. When the flood and ebb currents were around the setnet, the nets rised to the surface of water and it happened occasionaly at the stand of tide. Therefore, it was in the state that fish schools feel constraint to enter into the setnet, and was required a new design of the setnet stand up to strong tidal current. As the pure sound, of which frequency was 600Hz was emitted for the luring of fish schools in a setnet, the catch ammounts of fish, the young horce mackereWI'rachllrlls japonicus), was increased 4~6 times than not emitted.

• 수산해양기술연구
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• 제44권2호
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• pp.112-119
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• 2008

The fundamental data on the catch fluctuation in the rectangular set net according to the tide age were developed based on the catches recorded from the year 1986 to 2004 in the coastal waters of Hamdeok, Jeju. Total catch by the rectangular set net had a deep connection with the tide age. In particular, during increasing tide, total catch were reduced gradually from the neap tide to the high tide. As it turned out, the slope of total catch declined by degree and showed a correlation coefficient of determination of 0.76. On the contrary, in the case of decreasing tide, there was little sign of rise in total catch. In particular, large catch seemed to occur at the next tide to the neap tide. In the relation between the catch and the tide age, the level of the correlation coefficient chosen at $p{\leq}0.05$ decreased in the order rabbitfish(-0.84) and horse mackerel(-0.71), while the significance of other dominant species were not selected.

• 수산해양기술연구
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• 제47권4호
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• pp.356-368
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• 2011

Species composition of fishes and the recruitment properties of jack mackerel, Trachurus japonicus, in the waters around the Geumo Islands in the mid-South Sea were investigated by using both sides fyke nets every month from February to December 2010. During study period, a total of 30,503 fishes (1,380.4 kg) were collected and classified into 2 classes, 16 orders, 61 families and 121 species. The dominant species was jack mackerel occupying 80.5% of total individuals and 44.4% of total biomass. The fork length range of jack mackerel was 5.5-26.8 cm and individuals about 6 cm was appeared only in the middle and southern area of the Geumo Islands in May. The new recruitment of jack mackerel appeared from May in the waters around the Geumo Islands is probably caused by the warm water intrusion associated with the development of stratification due to the extinction of seasonal coastal cold waters by the increase of solar radiation heat. Furthermore, the jack mackerels less than 6 cm recruiting in the mid-South Sea in spring were considered as mixed ones by individuals spawned in the East China Sea and in the waters around the Jeju Island considering the collected time, migration period and spawning time of them.

• 한국해양생명과학회지
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• 제3권1호
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• pp.22-30
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• 2018

본 연구는 울릉도 수산자원 감소 문제를 해결하기 위한 방안 중 하나로서 정치성 구획어업의 도입을 위한 시험 연구를 수행하였다. 시험용 어구인 삼각망은 울릉도 해역의 환경, 운영 및 관리 비용, 소형 어선 및 인력이 운영할 수 있는 조건을 고려하여 선정하였다. 2017년 4월부터 5월까지 삼각망을 이용하여 11회 어획 조사한 결과, 총 개체수는 2,735개체, 중량은 983.4 kg으로 계측되었으며, 우점종은 참돔, 방어, 넙치, 한치, 전갱이, 쥐치류 등으로 조사되었다. 조사기간 중 유용 수산자원은 어류의 경우 조피볼락(Sebastes schlegelii), 볼락(S. inermis), 개볼락(S. pachycephalus), 쑤기미(Inimicus japonicus), 노래미(Hexagrammos agrammus), 농어목 어류 붉바리(Epinephelus akaara), 참돔(Pagrus major) 그리고 말쥐치(Thamnaconus modestus)로 분류되었으며, 두족류인 한치(Uroteuthis chinensis)의 어획량이 많은 것으로 분석되었다. 울릉도의 주요 수산자원 중 하나인 살오징어의 생산량이 지속적으로 감소할 경우, 삼각망과 같은 소형 정치성 구획어업의 도입은 어민 수입 창출의 대체 수단으로 유용할 것으로 판단된다.