• Fisheries and Aquatic Sciences
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• 제6권1호
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• pp.34-40
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• 2003

Three panel trammel nets were made illegal for the brown shrimp (Penaeus japonicus) or fishes by Korean fisheries law while trammel nets for fleshy prawn in the West sea remained legal. In this study a single panel tangle net with vertical loop lines rigged between the float line and sinker line was specially designed to catch brown shrimp. This net was developed for the first time after observation of the brown shrimp behaviour when reacting to a net in an observation tank. In field experiments these single tangle nets were compared with the traditional trammel nets in the coastal waters of the Keoje area. The mean number of the brown shrimp for 53 fishing operations was 1.13 per unit panel of the single tangle nets when fitted with the vertical loop lines. This was $84\%$ of the mean catch of 1.36 achieved with the trammel nets. These results of fishing experiments using single tangle nets in the field revealed a high fishing efficiency for the brown shrimp and showed little difference from trammel nets. The size of the brown shrimp or number of by-catch was not different between single tangle nets and trammel nets.

• 수산해양기술연구
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• 제48권4호
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• pp.322-336
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• 2012

To study the catching efficiency of biodegradable trammel net for swimming crab (Portunus trituberculatus), three types (biodegradable, monofilament and multifilament) of trammel nets were used in the field test, and the tests were carried out 16 times with two different mesh sizes (105mm and 160mm) in the Yeonpyeong fishing ground of Korea, 2009~2011. The catching efficiency of three type nets was analyzed by catch in number, catch in weight and average weight per individual of small and large size swimming crab by net types and mesh sizes. Statistical T-test was also carried out to verify the efficiency between the three types of nets. The results are as follows. The catch in number of swimming crab was 24,667 and formed about 81.0% of total catch. Of all swimming crab catch, small swimming crabs with less than 64mm in carapace length which is a prohibited landing size by law formed 48.1%, larger swimming crabs with more than 64mm in carapace length which is a landing size formed 51.9%. In 105mm mesh size trammel net test, the catch share in number of small size swimming crab by biodegradable trammel net was 47.5% in comparison with multifilament trammel net and 74.2% in comparison with monofilament trammel net, so biodegradable trammel net has more protective effects on small size swimming crab than other types of trammel nets. The protective effects for small size swimming crab by biodegradable trammel net was 25.8~52.5% in comparison with other types of trammel nets. The catch share in weight of large size swimming crab by biodegradable trammel net was 98.3% in comparison with multifilament trammel net and 92.3% in comparison with monofilament trammel net, so biodegradable trammel net has a similar catch efficiency to multifilament trammel net. The results of 160mm mesh size trammel net test have shown similar results of 105mm mesh size trammel net test. This study shows that biodegradable trammel net is a more useful fishing gear than multifilament and monofilament trammel net because biodegradable trammel net has lower catch rate than other types of nets in small size swimming crab and similar catch rate than multifilament trammel net which is a well used net by fishermen.

• 수산해양기술연구
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• 제50권1호
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• pp.1-11
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• 2014

To compare the catches made using gillnets, trammel nets, and gillnets with supporting lines, several experiments were conducted with commercial vessels near Uljin and Pohang in Eastern Korea between July 2010 and May 2011. Two sets of 13 different nets were used, including 5 panels of gillnets and trammel nets each with stretched mesh sizes of 7.6, 9.1, 10.6, 12.1, and 13.6 cm and 3 panels of gillnets with a mesh size of 9.1 cm with supporting lines with different line spacing. The outer (stretched) mesh size of the trammel nets measured 51.5 cm. The target fishes of the fishing nets were various types of flounders. The catch rate of flounders was 50.7% of the total catch in weight. The total catch for all nets was 443.8 kg. The predominant species was pointhead flounder (Cleisthenes pinetorum). The total catch by trammel nets was 1.4 times that of the comparable gillnets. But more pointhead flounder were caught by gillnets than by trammel nets, though there was no significant difference. Fishermen catching the pointhead flounder in Korea said that there was no need to use trammel net to catch it; this was an unexpected finding compared to the findings of other flounder fisheries. The amounts of roughscale sole, brown sole, and blackfin flounder caught by trammel nets were greater than those caught by gillnets. The mean lengths (standard deviation) of blackfin flounder, pointhead flounder, brown sole, and roughscale sole were 21.0 (4.57), 22.9 (3.40), 24.7 (4.90), and 28.3 (5.43) cm, respectively; there were significant differences in mean length (p < 0.00001). Therefore, in order to catch flounder efficiently, the fishing nets and mesh size should be chosen according to the target species. One advantage of using supporting lines is that it prevents breakage by strengthening the material especially when utilized on a rough bottom. Catch by using gillnet with supporting lines was not greater than that by using trammel net for the conservation of fisheries resources.

• 수산해양기술연구
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• 제38권2호
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• pp.91-100
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• 2002

삼중자망의 망목 선택성 및 적정망목을 추정하기 위하여 강원도 주문진 해역에서 2000년 8월 10~13일, 11월 9~13일 (18회), 부산 수영만에서 2001년 6월 1일~27일(21회), 시험조업을 행하였다. 또한 주문진 해역에서는 60, 75, 90 105, 135, 150, 180mm의 7가지의 삼중자망으로 조업하였고, 수영만에서는 60, 75, 90mm의 삼중자망과 홑자망으로 비교실험을 행하였다. 망목 선택성 곡선의 분석은 전체 어획량의 약 60%를 차지하는 물가자미(Eopsetta grigorjewi) 를 대상으로 하였으며, Master curve의 다항식이 포함된 Kitahara(1968)방법을 사용하여 작성하였다. 그 결과를 요약하면 다음과 같다. 1. 총 어획미수는 삼중자망이 2,331미였고, 홑자망이 1,433미였으며, 가자미류가 59.8%~60%였다. 2. 최적 l/m값은 삼중자망이 2.56이었으며, 흩자망이 2.47로 삼중자망이 약 0.1 정도 크게 나타났다. 3. 50% 선택구간은 삼중자망이 1.88~3.36(1.48)로 나타났으며, 홑자망은 2.00~3.02(1.02)로 삼중자망이 약 1.5배 정도 넓게 나타났다. 4. 가자미의 최소성숙체장 265mm에 대한 적정망목은 삼중자망이 약 141mm, 홑자망이 약 132mm로 삼중자망이 약 10mm 정도 크게 나타났다. 5. 적정망목을 사용했을 경우 50% 선택 체장범위는 삼중자망이 265mm~474mm, 흩자망이 265mm~398mm로 삼중자망의 체장범위가 76mm 정도 넓은 것으로 나타났다.

• 수산해양기술연구
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• 제49권1호
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• pp.1-17
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• 2013

The investigation for species composition and catch in the Korean deep-water of the East Sea (also known as Sea of Japan) was carried out with trammel nets of 7 mesh sizes (6.1~24.2cm) offshore Donghae (2006) and Yangyang (2007) of Korea. The catches were 1,268kg and composed of 37 species between 200m and 1,200m in depth. The principal species caught were Taknka's snailfish, salmon snailfish, red snow crab, hunchback sculpin, snow crab, spinyhead sculpin, Tanaka's eelpout, Alaska cod and so on. Those were target fish for commercial value except salmon snailfish. The mesh sizes for the largest catch were 10.6cm and 15.2cm in the fishing ground of Donghae and Yangyang, respectively. The habitat of snow crab was shallower than that of red snow crab in both areas. Trammel net enabled to investigate fish in deep-water with small fishing vessel and rather cheap expenses in contrast to bottom trawl that required too much of it. With increasing inner mesh size of trammel net the mean size of some principal species such as Taknka's snailfish, spinyhead sculpin, hunchback sculpin, Pacific cod, snow crab, red snow crab and hybrid between snow crab and red snow crab tended to be large in certain range of mesh size.

• 수산해양기술연구
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• 제45권2호
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• pp.96-105
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• 2009

For an effective management of fisheries resources, we need fisheries informations necessary for the establishment of reasonable fishing effort and TAC distribution. We carried out fishing research using trammel nets in the coastal sea of Susan-port(Yangyang, Gangwondo, Korea) and Hupo-port(Uljin, Gyeongbukdo, Korea) and analyzed fishing power variation of the fishing gear in terms of species composition, condition and so on for both sites. A total of 29 species were caught with most dominant species of Hippoglossoides dubius followed by Pseudopleuronectes herzensteini, Lophius litulon and Alcichthys elongatus in Susan. The total number of species caught in Hupo was 37 species with most dominant species of Todarodes pacifius followed by Lophius litulon, Hexagrammos agrammus and Pseudopleuronectes herzensteini. CPUE of Susan fishing area per trammel net was 12.74 fish and 2.00kg on average, while it was 6.80 fish and 2.27kg on average for Hupo. The fishing power index for both sites was 1, placing the two fishing grounds in a same level.

• 수산해양기술연구
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• 제53권4호
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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.

• 수산해양기술연구
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• 제46권2호
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• pp.103-114
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• 2010

For an effective management of fisheries resources, we need fisheries informations necessary for the establishment of reasonable fishing effort and TAC distribution. To study the present state of by-catch and discard of gill-net fishery in the East Sea, we carried out fishing research using trammel nets in the coastal sea of Susan-port (Yangyang), Jangho-port (Samcheok) and Hupo-port (Uljin). As a result, a total of catch of Susan was 259,172g and that of Hopo was 577,638g. Thus Catch of Susan was 1.49 times more than that of Hupo considering the number of used fishing gear. And catch of Janho was 7.4 times more than that of Susan considering the number of experiment. Two methods of by-catch analysis in this study were used, one method is standardizing of listed species catching possible in fishing license, another method is regarding catch species under 1% of total catch as by-catch. As a result of by-catch analysis of two method, by-catch rate of Susan was 6.55% and 5.87% respectively, that of Hupo was 44.70% and 5.24% and that of Jangho was 0.96% and 2.31%. Discard rate of fish in Susan, Hupo and Jangho were 1.59%, 3.42%, 2.23% respectively.

• 한국수산과학회지
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• 제48권6호
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• pp.947-959
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• 2015

Variations in the species composition, biomass and size distribution of fisheries resources in the Uljin marine ranching area were investigated using trammel nets at two stations (artificial reef and natural rocky area) from 2009 to 2010. During the survey, a total of 74 species were sampled with a mean density of 132 ind./net and mean biomass of 21.56 kg/net. In the natural rocky area, a total of 45 species were sampled at a mean density of 202 ind./net and mean biomass of 28.81 kg/net, while in the artificial reef area, samples included a total of 56 species, with means of 62 ind./net and 14.30 kg/net. The dominant species, comprising over 3% of the total number of individuals, were Suberites ficus (30.8%), Ovalipes punctatus (19.2%), Paralichthys olivaceus (11.7%), Pleuronectes herzensteini (4.7%), Kareius bicoloratus (3.5%), Pseudopleuronectes yokohamae (3.5%) and Eopsetta grigorjewi (3.0%). The dominant species, in terms of biomass, comprising over 5% of the total biomass, were P. olivaceus (22.1%), S. ficus (18.7%), O. punctatus (7.2%), Hexagrammos otakii (6.6%), P. yokohamae (5.7%), K. bicoloratus and P. herzensteini (5.3%). A cluster analysis and non-metric multidimensional scaling (nMDS) analysis based on the Bray-Curtis similarity of fourth root transformed data for number of species and individuals, was divided into two groups: the artificial reef area (group A) and the natural rocky area (group B).

• 환경생물
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• 제33권1호
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• pp.27-33
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• 2015

2005년 6월, 9월, 12월 및 2006년 3월에 동해안의 감포연안에서 저층삼중자망에 어획된 어류 종 조성을 분석하였다. 조사기간 동안 총 21과 32종, 695마리, 180,012.0 g의 어류가 채집되었다. 채집된 어류 가운데, 가장 많이 채집된 종은 망상어 (Ditrema temminckii)로서 채집 개체수의 52.4%, 생체량의 40.4%를 차지하였다. 그 다음 주요 종으로는 쥐노래미 (Hexagrammos otakii), 조피볼락 (Sebastes schlegelii), 쥐치 (Stephanolepis cirrhifer), 탁자볼락 (Sebastes taczanowskii), 용치놀래기 (Halichoeres poecilopterus) 등이었다. 이들 6종은 전체 개체수의 77.6%, 전체 생체량의 77.5%를 차지하였다. 종수, 개체수 및 생체량은 계절에 따라 변동하였다. 종수는 2005년 6월에 가장 많았고 2006년 3월에 가장 적었다. 개체수와 생체량은 2005년 9월에 가장 많았고, 2005년 6월에 가장 낮았다.