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

• Fisheries and Aquatic Sciences
• /
• 제24권1호
• /
• pp.41-52
• /
• 2021

Data for fish species composition and the catch of fish species were obtained from the daily trading records for the period between April and December 2016 to 2018 at the set net fishing grounds in Yeosu Bay, Korea. The annual mean total catch was 195.8 tons, and the dominant species was the Spanish mackerel (Scomberomorus niphonius), which accounts for about 55 percent of the total catch. The catch increased in spring and autumn. Increase in spring is caused by not Spanish mackerel but other fish while the increase in autumn by Spanish mackerel. The distinct increase of the catch in summer, 2017 was due to the new recruitment of small-sized Spanish mackerel, which was probably to be from the fish population hatched in spring in the East China Sea. Our results showed a strong correlation between water temperature and catch fluctuation. The catch increases with the increase in water temperatures, and the periodic pattern of the water temperature and catch fluctuation is more consistent in the offshore waters, in which warm current flows, than in the coast waters.

• 한국수산과학회지
• /
• 제42권1호
• /
• pp.83-88
• /
• 2009

The purpose of this paper is to obtain the fundamental data on the catch fluctuation in the pound set net according to the tide age from the catch recorded from the year 1997 to 2004 in the coastal waters of Guideok, Jeju. Total catch by the pound set net had a little connection with the tide age. During increasing tide, total catch were reduced slightly from the neap tide to the high tide while there seemed to be a little sign of rise in the total catch until decreasing tide. But in the relation between the catches and the tide age, the level of the correlation coefficient chosen at $p{\le}0.05$ was not significant. Therefore, the catch of the pound set net seemed not to be influenced by the tide age. In addition, CPUE at the high tide was higher than that at the neap tide. When the catch per operating frequency was graded in the order under 50 kg, 50-100 kg and 100-200 kg, the frequency rate by the pound set net was 38%, 19% and 19%, respectively.

• 수산해양기술연구
• /
• 제45권4호
• /
• pp.211-222
• /
• 2009

The fisheries resources by a set net in the coastal waters off Neungpo, Goeje Island from 2003 to 2004 were studied to determine species composition and catch variation. The main fishing period by a set net were from April to December in 2003 and from May to December in 2004. A total weight of 48 species caught through the survey period was 540,688.0kg. Most of them were 44 species of fishes and a few were 4 species of cephalopods. Dominant species was Trachurus japonicus accounting to 57.5% in total catch. Sub-dominant species were Trichiurus lepturus(12.9%), Engraulis japonicus(10.6%), Scomber japonicus(6.9%), Clupea pallasii(4.5%), Todarodes pacificus(2.8%) and Parapristipoma trilineaturm(1.3%). The remnant species showed a low catch, indicating the catch had less than 1% in total, respectively. T. japonicus and T. lepturus were caught throughout the survey period, but C. pallasii, Gadus macrocephalus, Oncorhynchus keta in low temperature season and Thunnus obesus in high temperature season. The fishing ground temperature was 11.7-24.0${^{\circ}C}$ in range and the catch by a set net was higher in autumn than in spring and in summer with the variation of fishing ground temperature. The annual catch by a set net was much higher in 2004 than in 2003 due to high temperature(>17${^{\circ}C}$) and the recruitment of T. japonicus from offshore seas. Therefore we concluded that the catch of Neungpo fishing ground by a set net was highly related to the variation of T. japonicus catch with fishing ground temperature.

• 수산해양기술연구
• /
• 제46권2호
• /
• pp.103-114
• /
• 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
• /
• 제37권1호
• /
• pp.65-72
• /
• 2004

Fish catch by a set net in Hamdeuk fishing ground off Jeju Island were studied to determine seasonal variation of species composition and catch from 1998 to 2000. A total 72,022.9 kg was caught during the survey period, including Scomber japonicus and Trachurus japonicus of $76.4\%$ in the total. The other dominant species were Siganus fuscescens, Loligo chinesis, Seriola dumerili, Sepioteuthis lessoniana, Sardinops melanostictus, and Seriola lalandi accounting to $20.0\%$ of the total. The fishing period conducted by a set net in Hamdeuk fishing ground were from May to November. The catch by a set net were higher in summer than in spring and autumn and closely related with the seasonal variation of sea water temperature. The catch was higher in 1998 than In 1999 and 2000, which was related to the sea water temperature in fishing ground.

• 수산해양기술연구
• /
• 제53권4호
• /
• pp.349-356
• /
• 2017

The catch composition of commercially important species of the stationary lift net at Barangay Gines, Miagao, Iloilo, the Philippines was investigated from December 2013 to May 2014 during the different phases of the moon. A total of 486 kg of fish coming from 12 different genera, including mollusk and crustaceans, was caught and identified from the catch of the stationary lift net. Among the 12 genera identified from the catch of stationary lift net, anchovy (Stolephorus), sardines (Sardinella), squid (Loligo) and mysid shrimp (Acetes) were considered to be commercially important due to their value. Acetes catch was highest during the new moon in the month of January. Loligo catch was also high during the new moon except in the month of May. Stolephorus catch was also highest during the new moon except in the month of January. Sardinella catch was highest during the first quarter in the month of February. Full moon had the lowest catch all throughout the duration of the study while new moon had the highest catch during December 2013 to March 2014 and first quarter was the highest in the months of April and May.

• 해양환경안전학회지
• /
• 제16권3호
• /
• pp.259-268
• /
• 2010

20년간(1980-1999) 동해의 해구(위경도 $30'{\times}30'$)별 오징어(Todarodes pacificus) 총 어획량과 단위노력당 어획량(catch/gear/day, CPUE)을 분석하여, 특정 해역에서 오징어 어획량이 높은 원인을 물리(수온), 생물학적 환경 인자(동물플랑크톤 생체량)를 이용하여 분석하였다. 해구별 총 어획량과 CPUE는 1980년대보다 1990년대에 증가하였다. 20년간 평균어획량이 높았던 해구는 동해 남부 5개 해구(No. 87, 76, 82, 83, 88)이었고, CPUE가 높았던 해구는 울릉도와 울진 부근의 해구(No. 65, 71, 72, 78)로 나타났다. 동해 전체 해구에서 이들 특정 해구의 총 어획량과 CPUE가 차지하는 비율은 각각 35.1%와 62.1%였다. 총 어획량과 CPUE가 높은 해역은 쓰시마 난류의 북방한계 지표수온인 $10^{\circ}C$의 등온선의 상부 수층에 위치하였으며, $10^{\circ}C$ 등온선의 분포 위치에 따라 해구별 총 어획량과 CPUE가 다르게 나타났다. 해구별 동물플랑크톤의 생체량 분포와 오징어 어획량 간에는 높은 상관성이 나타나지 않은 반면, 전체 해구의 동물플랑크톤의 연간 총 생체량과 오징어 총 어획량의 시계열 변화 경향은 유사하게 나타났다.

• 수산해양기술연구
• /
• 제57권4호
• /
• pp.342-350
• /
• 2021

Although Korea operates various systems and policies for the management of fisheries resources, it is judged that a more systematic resource management policy is needed due to the continuous decrease in the production of coastal and offshore fisheries. In this study, the catch capacity was analyzed using the DEA technique for coastal and offshore fisheries. As a result, despite the decrease in the amount of fisheries resources and the number of fishing vessels, there was a trend of increasing fishing capacity. As of 2019, the total maximum catch of offshore fishery was estimated at 820,007 tons. The actual catch was 548,159 tons and the CU was measured to be about 66.8%, which was analyzed to be an excess of about 33.2% of the catch. The total maximum catch of coastal fisheries was estimated at 187,887 tons. The actual catch was also the same value and the CU was measured to be about 100.0%. Thus, it was analyzed that there was no excess in catch. For the management of fisheries resources, it is necessary to manage the fishing capacity. To this end, policies such as scientific TAC should be promoted as well as expanding the reduction of fishing vessels.

• 수산해양기술연구
• /
• 제59권4호
• /
• pp.290-300
• /
• 2023

This study aimed to identify the actual catch situation of offshore dredge gear which is newly regulated in the legislation. It's also conducted to identify the species composition, weight of the catch including the target species and incidental catches, and to provide the basic information necessary for the resource management of aquatic organisms caught by offshore dredge. During the investigation period (from September 2022 to May 2023), a total of 61 species appeared in the test operation sea of Boryeong, Chungcheongnam-do and Gunsan, Jeollabuk-do, with 31 species of fishes, 11 species of malacostraca, six species of gastropoda, five species of bivalvia, three species of cephalopoda, three species of asteroidea, one species each of asteroidea and holothuroidea appeared. According to the results of the test operation conducted in September and November 2022, the non-catch season of Atrina (Servatrina) pectinata, 1,203 shellfishes were caught out of 2,979 caught in number, showing a bycatch rate of 59.6%, and by weight, 157.9 kg of shellfish was caught out of the total catch of 448.4 kg, showing a bycatch rate of 64.8%. On the other hand, in February and May 2023, the catch season for Atrina (Servatrina) pectinata, 3,692 fishsells were caught out of the 4,232 catches in total, showing a bycatch rate of 12.8%, and by weight, 1,185.0 kg of shellfish was caught out of the total catch of 1,293.2 kg, showing an 8.3% bycatch rate.