• Title/Summary/Keyword: Bottom gill nets

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Species Composition and Seasonal Variation of Fish Assemblages in the Coastal Waters off Gadeok-do, Korea 4. Fishes Collected by Bottom Gill Nets (가덕도 주변 해역 어류의 종조성과 계절 변동 4. 저층자망에 의해 채집된 어류)

  • AN Yong-Rock;HUH Sung-Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.6
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    • pp.686-694
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    • 2003
  • Monthly fish samples were collected using bottom gill nets and analyzed to study species composition and seasonal variation of fish assemblages in the coastal waters off Gadeok-do, Korea in 1998. During the study period, a total of 49 fish species representing 30 families were collected. The fish assemblages predominantly consisted of Limanda yokohamae, which accounted for $53.3\%$ of the number of individuals and $42.2\%$ in the biomass. The fish species, which had over 100 individuals, included Cynoglossus abbreviatus, Ditrema temmincki, Hexagrammos otakii, and Stephanolepis cirrhifer. These four species accounted for $24.1\%$ of the number of individuals and $24.3\%$ of the biomass. More fish species were collected in May and June than in any other months. The number of individuals and the amount of biomass peaked in April and May and reached a low in August. While the predominance of L. yokohamae caused the lowest species diversity by number of individuals in April, the predominance of Platycephalus indicus caused the lowest species diversity by biomass in July. Although gill nets show a strong selectivity for the target species or for size, gill nets can be used as an alternative fishing gear to collect fish in waters with rough bottoms, like rocky reefs, where other kinds of fishing gear such as trawls can not be used.

Study on the Improvement of Gill Nets and Trap Nets Fishing for the Resource Management at the Coastal Area of Yellow Sea -On the Present States of Gill Nets and Trap Nets Fishing and Body Length Distribution of Main Catch at the Coastal Area of Yellow Sea- (서해구 자원관리형 지망ㆍ통발 어구어법 기술개발에 관한 연구 - 서해구 자망ㆍ통발어업의 현황과 주어획물의 체장분포 -)

  • 장호영;조봉곤;박종수;두성균
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.1
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    • pp.50-55
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    • 2003
  • In order to study on the improvement of gill nets and trap nets fishing for the management of fisheries resource in the coastal area of Yellow Sea, we have investigated the general present condition of those fishing, and the actual fishing operation of gill nets for croaker and trap nets for rock shell which is called the the other trap nets, and then measured the body length of croaker and blue shell caught by their fishing vessels. The results are as follows ; 1. The total number of permission for coastal fishing are 12,944 cases, but the number of operation for coastal fishing are 7,558 cases in the coastal area of Yellow Sea. Among the total number of permission, the gill nets fishing are 5,154 cases with 39.8% but even so the number of operation are 3,724 cases, the trap nets fishing are 1,025 cases with 7.6% but even so the number of operation are 662 cases. On the fishing ratio, the gill nets and trap nets fishing are comparatively higher than the other fishing with 72.3% and 64.6%, respectively. 2. The main fishing period of gill nets for croaker is from the middle of July to early of September, and the main fishing grounds are sandymud bottom of 15-50m in depth around the islands of southern parts of western coastal area, and the fishing operation carry out 1∼2 times per day in flood tide and nets hauling conduct in 1∼2 hours after drifting with current. 3. The distribution range of body length of 139 croakers, which are caught in the gill nets, are 43.0∼120.0㎝ and the mode is 85.0㎝. 4. The main fishing period of trap nets for rock shell which is called the other trap nets is all the year round except the catching period of blue crab from early of September to the middle of October, and the main fishing ground are the sandymud bottom of 10∼20m in depth, and nets hauling conduct in next day after nets casting. 5. The distribution range of maximum carapace of 5,372 rock shells are 4.5∼8.5㎝ and the mode is 7.5㎝.

Recovery of Lost Fishing Gear in Alaska Pollack Fishing Ground of the East Coast in Korea (한국 동해안 명태어장에 분실된 폐어구수법에 관한 연구)

  • 안영일;박진영;조현정
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.1
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    • pp.9-17
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    • 2001
  • To improve the fishing environment of Alaska pollack fishing ground of the East coast in Korea, lost fishing gear were recovered from June to July 1998, May 1999 and from July to August 1999 in the sea near Goseong, Gangwon province. The lost fishing gear was recovered by grapnel. As the results, the lost fishing gear, which was consist of gill nets and traps, was produced from fishing activities, whereas most of them was the bottom gill nets. The weight of lost fishing gears was gill nets of 1,170 t and traps off 4t. The recovered gill nets decreased 12.02 t per mile from 22.74 t, in 1998 to 10.72 t, in 1999. Recovery rate of lost fishing gear was low as 38% in 1998, 41.9% in 1999 and CPUE was 11.27 t/trial in 1998, 7.48 t/trial in 1999. The recovery of lost fishing gear in fishing ground by using grapnel was considered as a useful method.

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Fish Assemblages Collected by Bottom Trammel Gill Net around Gampo in the East Sea of Korea (동해 감포 주변해역에서 저층삼중자망에 어획된 어류 군집)

  • Kang, Pil Jun;Kim, Chong Kwan;Hwang, Sun Wan
    • Korean Journal of Environmental Biology
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    • v.33 no.1
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    • pp.27-33
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    • 2015
  • Fish assemblages in the coastal waters off Gampo in the East Sea of Korea were analyzed using the samples of fishes collected with bottom trammel gill nets June, September, and December 2005 and, March 2006. During the study period, a total of 32 fish species, 695 individuals, and 180,012.0 g representing 21 families were collected. The fish assemblages predominantly consisted of Ditrema temminckii, which accounted for 52.4% of the number of individuals and 40.4% in the biomass. The next major specimens were Hexagrammos otakii, Sebastes schlegelii, Stephanolepis cirrhifer, Sebastes taczanowskii, Halichoeres poecilopterus. These six fishes accounted 77.6% of total number of individuals and 77.5% of total biomass. The number of fish species, the number of individuals and biomass were fluctuated with month. The number of species was highest in June 2005 and lowest in March 2006. The number of individuals and biomass was highest in September 2005 and lowest in June 2005.

Mesh selectivity of the bottom trammel net for spinyhead sculpin Dasycottus setiger in the eastern coastal sea of Korea (저층 삼중자망에 대한 동해안산 고무꺽정이 (Dasycottus setiger)의 망목 선택성)

  • PARK, Chang-Doo;BAE, Jae-Hyun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.53 no.4
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    • pp.317-326
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    • 2017
  • Comparative fishing experiments were conducted in the eastern coastal waters near Uljin, Korea from 2002 to 2004, using the experimental trammel nets to estimate the selectivity for spinyhead sculpin Dasycottus setiger. The inner panels of the nets were made of nylon monofilament with four mesh sizes (82.2, 89.4, 104.8, and 120.2 mm) while its two outer panels were made of twisted nylon multifilament with a mesh size of 510 mm. The SELECT (Share Each Length's Catch Total) procedure with maximum likelihood method was applied to obtain a master selection curve. The different functional models (normal, lognormal, bi-normal, and logistic model) were fitted to the catch data. The lognormal model with the fixed relative fishing intensity was chosen as the best-fitted selection curve through comparison of model deviance and AIC (Akaike's Information Criterion). The optimum relative length (the ratio of fish total length to mesh size) with the maximum relative efficiency was obtained as 2.492.