• 제목/요약/키워드: Demersal fishes

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제주도 마라도 연안해역의 어업생물자원에 대한 분포밀도의 음향학적 조사 (Hydroacoustic survey on distribution and density of fisheries resources in the Marado coastal area of Jeju, Korea)

  • 서영일;오택윤;차형기;이경훈;윤은아;황보규;이유원;김병엽
    • 수산해양기술연구
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    • 제52권3호
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    • pp.209-219
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    • 2016
  • The survey was conducted to investigate biomass and distribution of fisheries resources using a quantitative echo sounder and a fixed gillnet around Marado coast of Jeju to obtain the scientific basic data for dispute resolution with a large purse seine fishery and coastal fishing and policy establishment of reasonable fisheries resources. Hydroacoustic surveys were conducted six times (November 28~29, 2015 (night), February 23~24, 2016 (night) and March 3~4, 2016 (night/day), March 30~31, 2016 (night/day)) using a quantitative echo sounder. The pelagic fish densities were relatively higher around Marado in November 2015, February 2016 and March 3~4, 2016. However, demersal fish densities were relatively higher in Jeju coastal waters on March 30~31, 2016. Catch data using fixed gill net were used to calculate biomass. Based on the hydroacoustic data, fish length-weight function and target strength information of dominant fish, the biomass of fishes were estimated as follow: 5.64 ton CV = 70.2% at night on November 28-29 2015, 7.14 ton CV = 35.8% of pelagic fish and 530.77 ton CV = 34.6% of demersal fishes at night on February 23-24 2016, 2.34 ton CV = 56.7% of pelagic fish and 571.93 ton CV = 40.3% of demersal fish at daytime, 1.39 ton CV = 48.4% of pelagic fish and 194.59 ton CV = 54.3% of demersal fish at night on March 3~4 2016, 0.37 ton CV = 72.9% of pelagic fish and 338.79 ton CV = 99.7% of demersal fish at daytime, 0.24 ton CV = 21.3% of pelagic fish and 68.61 ton CV = 53.8% of demersal fish at night on March 30~31 2016.

Zoogeography of Taiwanese Fishes

  • Nakabo, Tetsuji
    • 한국어류학회지
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    • 제21권4호
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    • pp.311-321
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    • 2009
  • Three categories (freshwater, amphidromous, and marine fishes) of Taiwanese fishes are analyzed on the basis of zoogeographic elements, viz. China element, Indo-China element, Indo-West Pacific element, Indo-Pacific element, North-Pacific element, Japan-Oregon element, and circumtropical element. Freshwater fishes, which include the China and Indo-China elements, are distributed on part of the boundary area between the Palaearctic and Oriental regions of Wallace (1876). Diadromous fishes include the North-Pacific, Indo-China and Indo-West Pacific elements. Taiwanese salmon, a landlocked (initially diadromous) species that became established in Taiwan between 0.5 my B.P. and the early Pleistocene, is recognized as a distinct taxon included within the Oncorhynchus masou complex, which comprises here three species and two subspecies, viz. Oncorhynchus masou masou (Sancheoneo, Songeo, Sakura-masu or Yamame), O. masou ishikawae (Satsuki-masu or Amago), O. sp. (Biwa-masu), and O. formosanus (Taiwanese salmon), based on molecular, morphological and biological studies. Marine fishes are discussed under the following headings, brackish-water fishes (fishes of brackish waters and seas adjacent to continental coastlines, North Pacific and Indo-West Pacific elements; fishes of brackish waters and seas primarily around islands, Indo-West Pacific element), reef fishes (fishes of inshore reefs along continental coastlines from 0 to ca.100 m depth, Indo-West Pacific element; fishes of inshore reefs primarily around islands from 0 to ca.100 m depth, Indo-West Pacific element; fishes of offshore reefs along continental shelf edges from ca.150 to 300 m depth, circumtropical and Indo-Pacific elements; fishes of offshore reefs primarily around islands from ca.150 to 300 m depth, Indo-Pacific element), demersal fishes (fishes on continental shelves shallower than ca.150 m depth, Indo-West Pacific and Japan-Oregon elements; fishes on edges and upper continental slopes from ca.150 m to 500 m depth, Indo-West Pacific, Indo-Pacific, and circumtropical elements; fishes on lower continental slopes to abyssal plains from ca.500 m to 6,000 m depth, circumtropical element and rarely Indo-Pacific element), pelagic fishes (epipelagic fishes from 0 to ca.150 m depth, Indo-West Pacific, Indo-Pacific or circumtropical elements; meso- and bathypelagic fishes from ca.150 to 3,000 m depth, circumtropical element). The distribution of Taiwanese marine fishes are influenced by the Kuroshio Current, low-salinity and low-temperature waters from mainland China, and sea-bottom topography.

Biological environmental characteristics in Habitats of an abalone Haliotis diversicolor in the eastern coast of jeju-do, Korea

  • Yoo, Joon-Taek;Choi, Young-Min;Yang, Moon-Ho;Im, Yang-Jae;Ko, Joon-Chul;Chang, Dae-Soo
    • 한국패류학회지
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    • 제25권3호
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    • pp.231-236
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    • 2009
  • This study describes biological environmental characteristics in natural habitats of Haliotis diversicolor in the coastal area of Sungsanpo located in the eastern coast of Jeju-do, Korea. The field survey was monthly conducted from May 2006 to February 2007. H. diversicolor, sea urchin, turban shell and marine algae were collected by two divers using SCUBA. The species composition of demersal fishes were seasonally investigated by fish traps in 2007. During the study period, more than 67% of H. diversicolor and sea urchin were found in the depth shallower than 5 m, and more than 64% of turban shell were found in the depth deeper than 3 m. The dominant algal species in May were generally Undaria pinnatifida, Ecklonia cava, Sargassum. spp. and coralline algae. Most of demersal fishes collected by the fish traps were wrasses which have been reported as a major predator of young abalone.

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어자원 보호육성을 위한 생육환경 개선에 관한 연구- I - 소형저인망에 채집된 진해만 저서어류의 분포 - (Studies on the Growth and Environmental Development for the Protection-Nourishment of Fisheries Resources - 1. Distribution of Demersal Fishes in the Chinhae Bay. Korea -)

  • 김삼곤;김종화;박창두
    • 수산해양교육연구
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    • 제11권1호
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    • pp.98-113
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    • 1999
  • Demersal fishes as second study for the protection-nourishment of fisheries resources in Chinhae Bay were analysed using fish samples collected by a small otter trawler at bimonthly-interval from August, 1997 to June, 1998. Of the 55 species identified, Hexagrammos otakii, Pleuronichthys cornutus, Leiognathus nuchalis, Thrissa koreana, Callionymous lunatus, Acanthogobius flavimanus and Trachurus japonicus predominated in abundance. Especially, Hexagrammos otakii, Pleuronichthys cornutus and Leiognathus nuchalis were always collected at anywhere around a year in the bay. The seasonal fluctuation of number of species is very large as the ranging from 14 species in August to 25, December. The diversity index of individual number and biomass by month and station is 0.68(February)~1.13(October), 0.38(February)~1.06(October) respectively. The indices above mean that the number of species were not distributed broadly over the bay and also concentrated in several species only owing to the local pollutant extent.

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저서어자원량의 음향추정에 있어서 해저 데드존의 보정에 관한 연구 (Dead Zone Correction for Abundance Estimation of Demersal Fish by Acoustic Method)

  • 황두진
    • 수산해양기술연구
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    • 제36권3호
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    • pp.202-209
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    • 2000
  • 저서어의 음향자원조사에 있어서 해저 데드존에 의한 어군량의 추정오차에 관하여 고찰하기 위하여, 북해도 분화만과 동중국해 에 서 행 한 음향자원조사의 에코적분데이터를 이용하여 그 정도를 알아보았다. 그리고 해저상의 에코파형의 형상으로부터, 어군분포 패턴을 고려하여 데드존 내에 어군이 존재할 경우 그 에코파형을 발산형, 평행형, 수렴형으로 정의한 데드존 보정법을 제안하고 이를 이용한 보정을 행하였다. 북해도 분화만 내에 회유하는 명태어군을 대상으로 데이터를 재평가한 결과 해저 직상의 1∼2m내의 SV가 2∼3dB, 자원량으로 약 2배 증가하였으며, 동중국해의 경우에 있어서는 해저 직상 1∼2m에 어군이 집중되어 분포하고 있는 경우 SV가 최대 17dB까지 증가하였으며, 이는 자원량으로 약 50배 증가한 것 과 같았다. 끝으로, 계량어군탐지기를 이용하여 저서어의 자원량을 추정할 경우에는 해저기준의 최적화와 정확한 해저기준을 이용한 적분구간 오프셋 설정의 최소화를 달성한 후에 해저의 에코에 마스크되어 있는 어군의 에코를 어떠한 방법을 통하여 보정하여, 지금까지 기술적 곤란으로 제약을 점차 줄여 나감으로서 저서어를 대상으로 한 음향자원 조사 방법이 좀 더 고도화하여, 실용화할 수 있도록 노력해야 할 것으로 생각된다.

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Relationship between the Distribution of Water Masses and that of Demersal Fishes in the East China Sea in Spring

  • Cho Kyu Dae;Kim Hee Yong
    • Fisheries and Aquatic Sciences
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    • 제3권1호
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    • pp.14-22
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    • 2000
  • The relationship between the distribution of demersal fishes and that of the water masses was examined by using the catches data and hydrographic data in the Yellow Sea and the East China Sea on May 13-19, 1996 and May 10-17, 1997. During the study period, the dominant fish species were Cleisthenes pinetorum herzinsteini, Lophiomus setigerus and Pseudosciaena polyactis. These three low temperature water species accounted for $21-24\%$ of the total catches. The percentage of the low temperature water species was high in the Yellow Sea and the coastal area on the continental shelf of the East China Sea but was low in the vincinity of Kyushu during the study period. In the East China Sea, the isotherm of $15^{\circ}C$ at 50m, mid layer depth, was located more southeast in 1996 than in 1997. The bottom water temperature was about it lower in 1996 than in 1997. The direction of the detided current on the continental shelf of the East China Sea was southward in 1996 and northward in 1997. Yellow Sea Bottom Cold Water (YSBCW) strongly expanded to south in 1996 when the northward current was weak. But, Tsushima Warm Current (TSWC) strongly intruded into the continental shelf of the East China Sea in 1997. As YSBCW expanded strongly to south in 1996, the percentage of the low temperature water species relative to the total catches was high. But, TSWC strongly intruded and the percentage of low temperature water fishes was low in 1997.

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근해안강망어업의 발전과정 및 재편방향에 관한 연구 (A Study on the Development and Reorganization of the Stow-Net Fishery in Korea)

  • 김대영;일본명
    • 수산경영론집
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    • 제27권2호
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    • pp.65-82
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    • 1996
  • This study aims to investigate the development of the stow-net fishery operated in East China Sea and Yellow Sea and its role in the off-shore demersal fishery In Korea after 1980's. This paper also reorganization problems of this fishery under 200 mile exclusive economic zen system. Stow-net fishery which has an important role in offshore demersal fishery in terms of the fish production and supplies had attained an rapid growth since 1960's throughout advancement of the fishing technique, government support and enlargement of fish market. However, the production had come to a stagnant stage since 1980, and even reduced in 1990's by reason of competition from Chinese vessels which have been developing reapidly as well as other more productive demersal fishery such as trawl of Korea. Nevertheless, high fish price has maintained the business of this fishery. This fishery faces some difficulties such as limited resources, the plunge of fish price due to fish import freedom, and 200 mile EEZ settlement in those Seas among the related countries ratifying the United Nations Convention of the Law of the Sea in 1996. This paper discusses the reorganization problems of the stow-net fishery under the new situation. : (1)to lighten a damage to the fishery to keep the fishing ground and to restrict the entry of competitive fisheries, (2)to reduce the fishing effort by the governmental support, (3)to introduce new fishing methods, (4)to employ foreigner as a cheep labour, (5)to rise fish price throughout more freshness of fishes.

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북양 트로올 어업의 문제점 (Some Problems in the North Pacific Trawl Fisheries of Korea)

  • 이병기
    • 수산해양기술연구
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    • 제7권1호
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    • pp.39-43
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    • 1971
  • Koreans have been interested in the North Pacific fisheries since the exploratory fishing was carried out by R/V Baek-Kyung of Pusan Fisheries College in 1966. Although the salmon fishing was interrupted by some countries, Korean trawlers are venturing in the North Pacific Ocean for catching demersal fishes. The trawl fishery in the region raises some problems. i. e. the conflict with the coastal or nearshore fishery, low fish price, etc. This paper concerns with the plan for the settlement of these problems..

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동중국해 한일공동수역에서 저서 어획물의 분포특성 (Distribution Characteristics of Fishes by a Bottom Trawl in the Jointly Controlled Waters of the East China Sea)

  • 김민석;김동수
    • 수산해양교육연구
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    • 제22권3호
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    • pp.330-340
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    • 2010
  • This study was investigated the species composition of demersal fishes by a bottom trawler GAYA, in order to be used basic data for resources management of fishery in the jointly controlled waters of the East China sea. We caught 52 species, 1,167 individuals and 186.171kg in biomass in summer, and 1,924 individuals and 200.871kg in biomass in winter The first dominant species in individuals in summer was Glossanodon semifasciatus, and in biomass was Dentex tumifrons. But that in winter was Ovalipes punctatus in both individuals and biomass. It was a special phenomenon that crustacea was to be the first dominant species compared with general offshore fishery in Korea. Catch per unit effort (kg/hr) of bottom trawl in winter was higher than that in summer. There was also big difference by station in the diversity index, the evenness index and the dominant index.

대천 해빈 쇄파대어류 종조성의 단기 변화 (Short-term Variation in Species Composition of Surf-zone Fishes at Daechon Beach, the Yellow Sea of Korea)

  • 이태원
    • 한국어류학회지
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    • 제13권1호
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    • pp.32-39
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    • 2001
  • 대천 해빈 쇄파대에서 1990년 8월 사리와 조금 때 2시간 간격으로 24시간 동안 어류를 채집하여, 조차, 조위 밤낮에 따른 어류 종조성의 단기 변동을 분석하였다. 채집된 어류는 총 24종으로, 부어류의 유어들이 양적으로 많았고, 사리 간조 때에는 저어류의 유어들도 출현하였다. Wilcoxon의 signed-rank test 결과 사리 때가 조금 때에 비하여 유의하게 많은 양이 채집되었다. 사리 때에 는 만조 때에 비하여 간조 때 유의하게 많은 어류가 채집되었으나, 조금 때에는 간조와 만조 때 유의한 차이를 보이지 않았다. 부어류들의 평균 개체수는 사리와 조금 때 유의한 차이를 보이지 않았지만, 대부분의 저어류들은 사리 간조 때에 유의하게 많이 잡혔다. 채집된 대부분의 저어류들은 사리 간조 때 대부분 채집되어, 저어류들은 대부분이 조금 때 간조선 보다 깊은 곳에 서식하는 것을 알 수 있다.

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