• Ocean and Polar Research
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• 제39권3호
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• pp.221-232
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• 2017

The purpose of this study is to estimate the extent of fisheries resource rebuilding and other economic effects on coastal gill-net fishery as a result of the Korean vessel buy-back program using with-without analysis based on methods estimating sustainable yields for all species caught by coastal gill-net fishery. Based on the results of with-without analysis, maximum sustainable yields (MSY) of all species caught by coastal gill-net fishery have been increased by the Korean vessel buy-back program. In addition, profits per vessel of maximum economic yield (MEY) of the species have been improved by the program. Further, yields and a producer surplus per vessel under an equilibrium of open access (OA) have increased because of the program. In detail, first of all, at the MSY level, the vessel buy-back program has led to about 21% fisheries resource recovery, and at the MEY level, it has led to about a 19% resource recovery. Secondly, at the MEY level and the OA level, the producer surplus per vessel has been increased by about 24% and 22% respectively by the vessel buy-back program.

• 수산해양기술연구
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• 제53권1호
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• pp.41-48
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• 2017

Encircling gill net fishery is a kind of gill net which is generally used in shallow coastal waters. After the fish have been encircled by the gill net, noise stimulus such as a stone or sound is used to force them to gill or entangle themselves in the netting surrounding them. Although the fishing by a stone is a traditional fishing method, it is considered as an illegal fishing method by physical stimulus such as explosives and mechanical vibrator. However, this illegal fishing method has raised some problems to the fishing boat of other fisheries or many anglers due to disturb aggregating fish schools. This study is aimed to provide scientific base data to verify whether to impact the ecosystem caused by this encircling gill net. This study exhibited that the impulse noise by concrete sphere in the encircling gill net was $159dB/{\mu}Pa$, the ambient noise from ship engine was $160dB/{\mu}Pa$, and the maximum noise from continuous artificial vibrator was $175dB/{\mu}Pa$. These may be stimulus to the escape of fish distributed in a wide area in its natural state; it is not likely the cause of death due to catastrophic stress. Therefore, it needs to prepare the consideration of standard limit on fishing stimulus in fishing methods of the fishery laws and regulations, prevent fishermen form using illegal fishing gear (i.e. explosive sound standards: $200{\sim}220dB/{\mu}Pa$ and provide them with countermeasures.

• 수산경영론집
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• 제43권3호
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• pp.43-57
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• 2012

According to the result of the recent survey on the current condition of loss of the fishing gears in the East, West and South seas, it is estimated that 50% of the fishing gears used for coastal trap and gill net fisheries are lost every year and 20~30% of those used for inshore trap and gill net fisheries are lost. It is reported that such loss of fishing gears leads to the loss of about 10% of 1.7M tons of the total annual catch from the gill nets and traps along the country's coasts and shores, which amounts to 15~170K tons. Submerged marine litters that have recently been accumulated because of the washed out or lost fishing gears significantly affect the development of fisheries resources as well as the natural environment. The purpose of this study is to identify the damages that the ever-increasing submerged marine litters of washed out fishing gears would have on the fishery and to analyze the effects of the coastal and inshore submerged marine litter collection business on the fishery management. For this, the economic analysis was carried out for the coastal and inshore submerged marine litter collection business based on the fishermen's expenses and earnings and their catch. The result of the analysis shows that the submerged marine litter collection business is quite effective in certain areas but rarely effective in other areas. However, taking into consideration that the litter collection would contribute to protecting the marine environment as well as the fisheries resources, it is expected to have a significant impact on the protection of the marine environment even in those areas where it is not effective for the protection of the fisheries resources.

• 수산해양기술연구
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• 제40권3호
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• pp.182-188
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• 2004

홑자망과 삼중자망에 의한 어획성능을 파악하기 위하여 한국 남해안의 거문도연안에 시설된 세라믹 어초어장에서 어구 성능시험과 수중 비디오 카메라로 어군 위집상을 조사로 하였다. 흩자망에 의한 폭당 어획량은 삼중자망에 비해 49.2% 많았으나, 어종수는 34.5% 적었는데, 이를 ANOVA로 분석한 결과 5% 유의수준에서 차이가 없었다. 어구별 우점종은 홑자망에서 참돔 1종, 삼중자망에서 참돔, 말쥐치, 홍어 등 3종이었으며, 홑자망에의해 어획된 참돔의 체장범위와 평균체장은 삼중자망에 어획된 참돔보다 다소 적게 나타났다. 홑자망에 의한 어획성능이 삼중자망보다 높았던 원인은 홑자망에 어획되기 쉬운 어종이 군을 형성하고 있었고, 개체의 크기도 홑자망에 적합하였기 때문이라고 판단된다.

• 수산해양기술연구
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• 제55권4호
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• pp.294-302
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• 2019

As a series of fundamental researches on the development of an automatic identification monitoring system for fishing gear. Firstly, the study on the installation method of automated identification buoy for the coastal improvement net fishing net with many loss problems on the west coast was carried out. Secondly, the study was conducted find out how to install an automatic identification buoy for coastal gill net which has the highest loss rate among the fisheries. GPS for fishing was used six times in the coastal waters around Seogwipo city in Jeju Island to determine the developmental status and underwater behavior to conduct a field survey. Next, a questionnaire was administered in parallel on the type of loss and the quantity and location of fishing gear to be developed and the water transmitter. In the field experiment, the data collection was possible from a minimum of 13 hours, ten minutes to a maximum of 20 hours and ten minutes using GPS, identifying the development status and underwater behavior of the coastal gillnet fishing gear. The result of the survey showed that the loss of coastal net fishing gear was in the following order: net (27.3%), full fishing gear (24.2%), buoys, and anchors (18.2%). The causes were active algae (50.0%), fish catches (33.3%) and natural disasters (12.5%). To solve this problem, the installation method is to attach one and two electronic buoys to top of each end of the fishing gear, and one underwater transmitter at both ends of the float line connected to the anchor. By identifying and managing abnormal conditions such as damage or loss of fishing gear due to external factors such as potent algae and cutting of fishing gear, loss of fishing gear can be reduced. If the lost fishing gear is found, it will be efficiently collected.

• 한국수산과학회지
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• 제47권6호
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• pp.1037-1054
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• 2014

In this study, the status of coastal fisheries was examined based on the catch and number of fishing vessels of coastal fisheries in Korea. Comparing the status on coastal fisheries of the East Sea, Yellow Sea and South Sea in Korea, scientific evidence was made for fisheries management on coastal fisheries based on characteristics of each sea area. From 1990 to 2011, the catch of coastal fisheries in Korean waters ranged from 150,000 mt to 230,000 mt, with an average of 190,000 mt, and it accounted for 15% in average of total catch fished in adjacent waters of Korea. In order of catch by coastal fisheries, gillnet (36.7%) was the primary fishery, followed by coastal complex (24.7%), stow net (18.3%), trap (12.9%), lift net (3.9%), purse seine (3.0%) and beam trawl (0.4%) fisheries. In order of catch by species, anchovy (15.0%) had the largest proportion of total catch, followed by common squid (10.3%), akiami paste shrimp (5.2%), blue crab (3.9%) and octopus (3.7%). Of the average catch by sea area from 1990 to 2011, Yellow Sea, South Sea and East Sea were 37.4%, 34.6% and 28.0%, respectively. Since 2000s, however, the average catch of South Sea has accounted for the largest proportion. The number of permitted fishing vessels involved in 8 coastal fisheries was 55,336 vessels in average from 1997 to 2011. The number of vessels was about 47,000 vessels in 1997, and increased to 61,300 vessels until 2000, then has decreased to 44,000 vessels operating in 2011. In order of the number of permitted fishing vessels by fisheries, complex (52.4%) took the first place, followed by gillnet (31.5%), trap (13.4%), stow net (0.8%), beam trawl (0.8%), purse seine (0.6%), lift net (0.4%) and seine net (0.0%). In order of the number of permitted fishing vessels by sea area, South Sea (29,994 vessels) took the first place, followed by Yellow Sea (18,185 vessels) and East Sea (7,158 vessels). In order of the catch per unit effort (CPUE, mt/vessels) which was analyzed using catch and number of vessels in average by fishery, stow net is the highest followed by lift net, trap, purse seine, gill net, beam trawl and complex fisheries. In particular, the CPUE of complex and gill net fisheries, which accounted for the largest number of vessels were 4.0 mt/vessels and 1.6 mt/vessels, respectively. Since those are too low relative to other fisheries, it was judged to need systematical management on both fisheries.

• 수산해양기술연구
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• 제48권4호
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• pp.387-400
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• 2012

Species composition and seasonal variation of aquatic organism in the coastal waters off Taean, Korea were investigated using catches by commercial fishing of the pot and gill net from April 2010 to January 2011. A total of 58 species, 10,602 individuals and 547,569g of aquatic organism were collected during the study. Aquatic organism were composed of 22 species of Pisces, 20 species of Crustacea, 8 species of Gastropoda, 3 species of Echinodea, 2 species of Cephalopoda and Bivalvia, and 1 species of Holothuroidea. 41 species in 9 orders and 22 families were collected by the pot, and 28 species in 15 orders and 22 families were collected by the gill net. Volutharpa ampullacea was the most dominant in the pot, while Okamejei kenojei was the most dominant in the gill net. These two species accounted for 73.9% in the number of individuals, and 64.4% in biomass. The number of species was high in spring in the pot, and autumn in the gill net. The number of individuals and biomass were highest in winter and summer respectively in the pot, and summer in the gill net. The number of species of the consignment quantity caught by commercial fishery of the pot and gill net in Mohang was 12 and 14 respectively. Cluster analysis based on species composition of the 18 most common species showed that the species were separated into 3 different group. Group A was composed of species which were abundant in spring, group B was composed of species which were abundant in summer and autumn, and group C was composed of year-round residents.

• 해양환경안전학회지
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• 제25권5호
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• pp.535-541
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• 2019

본 연구는 해상풍력발전단지 내 어업의 가능성을 살펴보고자, 어구 및 어법이 해상풍력발전단지 내 터빈과 해저케이블에 미치는 위험도를 평가하였다. 서남해 해상풍력발전단지를 연구 대상 해역으로 설정하여, 주변 국가어항의 선박 현황을 조사하였다. 어선의 현황을 참조하여 22개의 어구 및 어법에 대하여 위험도 평가 기준을 설정하고, 전문가를 통해 위험도를 평가하였다. 위험도가 낮아 해상풍력발전단지 내에서도 조업이 가능하다고 판단되는 어구 및 어법은 외줄낚시, 대낚시, 멸치챗배였으며, 위험도가 보통으로서 조업이 가능하기는 하나, 주의가 필요하다고 생각되는 어구 및 어법은 바닥주낙, 뜬주낙, 끌낚시, 오징어채낚기, 문어단지, 주꾸미소호, 연안통발, 주목망, 낭장망, 고정자망, 유자망이었다. 위험도가 높아 해상풍력발전단지 내 조업이 어렵다고 판단되는 어구 및 어법은 형망, 빔트롤, 건착망류였으며, 위험도가 아주 높아 해상풍력발전단지 내 어업이 허용되기 어렵다고 판단되는 어구 및 어법은 안강망, 기선권현망, 오터트롤, 외끌이기선저인망, 쌍끌이기선저인망이었다.

• 한국수산과학회지
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• 제54권3호
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• pp.318-328
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• 2021

We investigated the maturity and spawning of the brown sole Pseudopleuronectes herzensteini, in the coastal waters of the East Sea off Gangwon and Gyeongbuk, South Korea, using samples collected by gill net and longline fishery from January 2018 to December 2019. We analyzed oocyte development, monthly maturity stage, gonadosomatic index (GSI) and total length at maturity. Histological analysis of ovarian development in P. herzensteini revealed that the development was group-synchronous. The spawning peak in Gangwon and Gyeongbuk occurred from April to May and from February to March, respectively. Thus, the spawning season in Gangwon was 1-2 months later than that in Gyeongbuk. The length at 50% maturity for females was estimated as 24.2 cm and 19.0 cm in Gangwon and Gyeongbuk, respectively. Similarly, the length at 50% maturity for males was estimated as 19.8 cm and 16.5 cm in Gangwon and Gyeongbuk, respectively.

• 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.