• 수산해양기술연구
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• 제57권2호
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• pp.107-116
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• 2021

The breakdown of the Korea-Japan fishing negotiations since 2016 has made it impossible for many domestic fishing vessels to operate in the Japanese EEZ water, and large purse seine fishing vessels are one of them. Mackerel is a highly migratory fish species, circulating in the East China Sea, South Sea, West Sea and East Coast throughout the year, and goes through a period of wintering, spawning, growth and feeding migration. In this study, in order to find out the dependence of large purse seine fishing vessels on mackerel fishing in the Japanese EEZ waters, we analyzed the characteristics of mackerel by large purse seine fisheries in the Japanese EEZ waters from 2010 to 2016. The catch and fishing details were investigated. The total catch of mackerel by large purse seine fishery, the average catch rate of mackerel in Japanese EEZ is 4 percent per year. The amount is estimated at 10.2 billion won per year. Although there was an effect, it was not judged to be a significant factor, and it was found that the amount of catch and fish price in the domestic waters had a greater influence on the total catch than the Japanese EEZ waters.

• 한국수산과학회지
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• 제51권3호
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• pp.338-343
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• 2018

Recently, commercial catches of the common squid Todarodes pacificus have dramatically decreased in Korean and Japanese waters. The relationship between common squid catches and environmental factors was investigated using squid catches, climate indices and observed seawater temperatures in Korean waters. Common squid consist of three spawning stocks: autumn, winter, and summer. The autumn stock is the largest in Korea, and its main fishing season appears to have shifted from September in the 1980s to October in the 1990s. We observed negative correlations between the spring Southern Oscillation Index and Korean catches and between the winter Pacific Decadal Oscillation and Japanese catches. Despite global warming, no conspicuous increases in October seawater temperatures have been observed at 10 and 50 m in Korean waters since the mid-1900s. Instead, the 50 m water layer of the East Sea appears to be gradually cooling. Moreover, temperatures at 50 m in the East Sea and the South Sea were significantly negatively correlated with squid catches in Korea and Japan, respectively. Our preliminary analysis indicates a link between climate change, seawater temperature, and squid catches in Korean waters, which helps to inform the direction of subsequent research to identify the cause of rapid decreases in this squid resource.

• 생명과학회지
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• 제14권6호
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• pp.938-950
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• 2004

한국해역에 분포하는 멸치의 유전학적 특성을 연구하기 위하여 미토콘드리아 12S 리보좀 RNA 유전자배열 (339 bp)을 분석하였다. 황해남부, 제주연안, 남해동부 등 3지역의 시료로 부터 총 35 mtDNA의 haplotype을 구하였다. 황해남부에서 채집된 멸치의 AN8T103은 PAUP 분석에서 $0.2-4.1\%$로 분리되는 독립적인 계통을 보이므로서 다른 연구해역으로부터 유입된 개체군인 것으로 보이나 금후 추가연구가 필요하다. AN8T103을 제외한 유전자 다양성은 $0.3-3.8\%$로서 개체군 내 염기다양성은 0.015(황해), 0.013(제주도), 0.015(남해)로 나타났다. 암컷유전자이동은 상당히 높았으며(Nm=25.5-36.44), 지역간 유전자거리(FST)는 유의한 차를 보이지 않았다$(P>0.01)$. 이러한 결과는 한국해역에 서식하는 멸치가 지리적으로 무작위 분산된 개체군임을 암시한다.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.58-65
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• 1999

Fibrocapsa japonica (Raphidophyceae) is regarded as a harmful algal bloom organism in Japanese waters, where it has been linked to fish kills. Fibrocapsa is a common species in New Zealand coastal waters, particularly in the Hauraki Gulf, where it has regularly bloomed in the spring under E1 Nino climate conditions for the past six years. The New Zealand isolate had 1.4 times more total polyunsaturated acids than the Japanese isolate under the same growth conditions, suggesting that eicosapentaenoic acid in particular coold be used as a discriminating chemotaxonomic marker. The molecular probes tested showed no differential binding of the raphidophytes to lectins, but oligonucleotide probes targeted F. japonica ribosomal RNA bound specifically to both isolates. Neither strain was toxic in mouse or neuroblastoma bioassays. There is no evidence that the New Zealand F. japonica isolates investigated to date produce ichthyotoxins.

• Fisheries and Aquatic Sciences
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• 제26권7호
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• pp.455-459
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• 2023

40 species of the family Caprellidae Leach, 1814 are recorded in Korean waters. Caprella aino Utinomi, 1943 was newly collected from seaweed farms from the southeastern waters of Korea. C. aino was firstly reported in Japanese waters in 1943. Adults of C. aino and Caprella mutica Schurin, 1935 are easily distinguished in that C. aino have pereonite II and gnathopod II without setae and two small tubercles of articulation of gills in pereonite III-IV, while C. mutica do pereonite II and gnathopod II covered with setae and those of pereonites III-VII with many tubercles. However, subadult C. mutica is hardly distinguishable from C. aino in that tubercles of pereonite III are less developed and they have inconspicuous setae of pereonite II and gnathopod II. Nevertheless, C. aino is distinguished from subadult C. mutica because adult C. aino have dorsal tubercles on pereonite IV, V, VI, VII unlike that of C. mutica. We report C. aino as a new record in Korean water with comparison of C. mutica.

• Ocean and Polar Research
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• 제28권2호
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• pp.175-186
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• 2006

There are disputes for oil and gas development between China and Japan in the East China Sea. These involve the area where China is already carrying out activities of oil and gas development and where Japan is proclaiming its EEZ. China insists that the Chinese activities on oil and gas development area are being carried out within the Chinese jurisdictional waters even if the median line principle of Japanese proclamation is applied in delimitation. Indeed, the permit for Japanese development is causing disputes between China and Japan because its permit allows development in the waters adjacent to Chinese development area. h the event, the core of this dispute around the oil and gas field in the East China Sea relates to issues of maritime boundary delimitation and issues of resources acquisition with both states. Chinese policy on oil and gas development is to first consider development issues in accordance with a median line principle where waters toward to China from the median line should be developed by China and the area toward Japan from the median line within the Chinese continental shelf should be jointly developed. However, the Japanese position is that the East China Sea should be jointly developed, and Japan hopes to eventually convince China to accept its median line delimitation. With on-going development of such issues, Korea should establish a strategy of negotiation based on analyses of resource distributional conditions and other strategic factors in the Korean delimitation area. In particular, Korea should prepare and make the best use of joint development zone established in an agreement between the ROK and Japan concerning the development of the southern part of continental shelf adjacent to both states.

• Ocean and Polar Research
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• 제30권3호
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• pp.249-258
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• 2008

이석(otoliths)은 경골 어류의 내이(inner ear)에 존재하는 평형석으로 어류의 성장과 함께 성장하며, 이석 내 산소동위원소는 어류가 서식했던 수온에 영향을 받으며 침전되기 때문에 어류가 서식했던 서식처의 수온을 반영한다고 알려져 있다. 본 연구에서는 명태 이석 내 산소동위원소(${\delta}^{18}O$)와 서식 수온과의 관계를 조사하여, 명태의 생활사에 따른 서식지의 변동을 비교하였다. 우리나라와 일본의 동쪽 해역에서 $1997{\sim}1999$년 사이에 채집된 명태로부터 이석을 채취하여 연령대 별로 산소동위원소 함량을 분석하였으며, 수온 자료는 양국의 해양자료센터(KODC, JODC)로부터 획득하였다. 명태가 서식하는 수심의 수온은 가을과 겨울에 걸쳐 연중 가장 높았고, 우리나라 동해연안은 200 m 이상의 수심에서는 계절적 변동이 거의 없이 낮은 수온이 분포하는 안정된 상태였으나, 일본 해역에서는 300 m의 비교적 깊은 수심에서도 계절적 변화를 보였다. 전반적으로 모든 수심에서 우리나라 보다 일본 연안의 수온이 높았으며, 일본 해역의 명태가 우리나라 명태보다 깊은 곳에 서식하였다. 우리나라와 일본 명태 이석의 산소동위원소 값은 대부분 시료에서 이석의 핵 부분 보다는 가장자리 부분에서 산소동위원소 값이 높아 명태가 성장하면서 수온이 낮은 깊은 수심으로 이동하는 것으로 이해된다. 또한, 3년 동안의 수온변화와 그 당시 성장하였던 이석의 산소동위원소 값은 역상관 관계를 보이고 있다.

• Ocean and Polar Research
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• 제23권2호
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• pp.141-160
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• 2001

The challenge of predicting the Japanese coastal ocean motivated Frontier Observational Research System for Global Change (FORSGC) and the Japan Marine Science and Technology Center (JAMSTEC) to start a multiyear observational programme in the upstream Kuroshio in November 2000. This field effort, the Kuroshio Observation Program (KOP), should enable us to determine the barotropic and baroclinic components of the western boundary current system, thus, to better understand interactions of the currents with mesoscale eddies, the Kuroshio instabilities, and path bimodality. We, then, will be able to improve modeling predictability of the mesoscale, seasonal, and inter-annual processes in the midstream Kuroshio near the Japanese main islands by using this knowledge. The KOP is focused on an enhanced regional coverage of the sea surface height variability and the baroclinic structure of the mainstream Kuroshio in the East China Sea, the Ryukyu Current east of the Ryukyu's, and the Kuroshio recirculation. An attractive approach of the KOP is a development of a new data acquisition system via acoustic telemetry of the observational data. The monitoring system will provide observations for assimilation into extensive numerical models of the ocean circulation, targeting the real-time monitoring of the Japanese coastal waters.

• Journal of Species Research
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• 제9권4호
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• pp.443-447
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• 2020

A newly recorded species Caprella arimotoi Takeuchi, 1993, belonging to the family Caprellidae Leach, 1814, was collected from the South Sea, Korea. This species is morphologically very similar to Caprella verrucosa Boeck, 1871, with blunt dorsal projections on pereonites, oval-shaped propodus on gnathopod 2, and grasping spines on the pereopods 5-7. Caprella arimotoi originated from C. verrucosa and are difficult to distinguish because they have mixed characteristics. However, C. arimotoi was classified because of several morphological differences. The newly recorded species C. arimotoi is discernible from C. verrucosa by a forwardly curved anterodorsal projection on head, elongated gills, slender pereopod 7, and lacking ventrolateral projections on pereonites 2-7. To date, C. arimotoi has only been reported in Japanese waters. So, our record is the first record in Korean waters and outside of Japan. In this study, the Korean C. arimotoi is illustrated based on the mature male specimens with a brief description of the female, focusing on the sexually dimorphic characters.

• Animal Systematics, Evolution and Diversity
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• 제36권4호
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• pp.400-407
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• 2020

An epialtid spider crab, Naxioides robillardi (Miers, 1882), is known as widely distributed in Indo-West Pacific region include Japanese waters. Four specimens of epialtid crabs were collected from adjacent waters of Jejudo Island and identified as N. robillardi. This species can be grouped into two forms such as N. robillardi form typical and N. robillardi form mammillata according to morphological features of carapace, gastric spine, and chela. Morphological characters of all Korean specimens well agree with the form mammillata in general. In this paper, morphological diagnosis and illustrations of newly collected N. robillardi are provided. DNA barcode sequence of COI region is also determined for the first time.