• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.4
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• pp.177-183
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• 1987

The catch by the set net fishery from 1971 to 1985 were analyzed in order to reveal its fluctuation characteristics. Generally, the catch increased from 16,787M/T in 1971 to 84,103M/T in 1985 and showed maximum in 1979 with 99,475M/T of catch. This trend was mainly related to the higher production of file fish which accounts for 64% of the total catch in 1979, and the change of catch statistical classification according to the revising of fishery law in 1976. It was also closely related to the variation of the sea water temperature in coastal area. The main fishing period of the set net fishery appeared from October to November. Catch of the set net fishery was led by that in the southern coast before 1976 and by that in the eastern coast from 1977 to 1980, the tendency changed irregular from 1981. Three groups of fishes could be distinguished by principal component analysis of the annual catch. A group showing steady decreasing tendency was composed of the fishes such as whiting, sand fish, hair tail and anchovy. The another group composed of small alaska pollack, round herring, goby, gizzard shad, sand lance and file fish revaled an increasing tendency. The other fishes did not show any annual tendency.

• Ocean and Polar Research
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• v.27 no.3
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• pp.311-322
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• 2005

Fisheries buyback programs in Korea have been implemented since 1994, and their scales are estimated to be the present value of 930 billion won for the last 9 yens since 1994. The paper attempts to identify the patterns of each fish species, of which their yields can be steadily increased or significant]y decreased, and to evaluate its effective level and the optimal level for buyback programs by means of fishing capacity analysis. The paper distinguishes fish species, that there is no need to reduce the fishing efforts, such as anchovies, mackerels, squids, Spanish mackerels, and herrings, because MSY exceeds yields, from fish species to control overfishing such as file fish, yellow corvenias, young pollack, hair tail, snow crab, and pollack. The paper also suggests that 65% of the fishing efforts (total tonnages) should be cut back at the national aggregate level in order to restore fish stocks.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.194-201
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• 2022

Purpose: This study investigated the relationship between climate factors and the catches in Korean offshore fisheries in recent three decades (1981 to 2010). Method: This study focused on seven types of fish species preferred in Korean cuisine. In the study, 10-year moving averages were used so that long-term trends could be easily identified. Results: Both air temperature and sea surface temperature (SST) on the coast of Korea rose in the period (p < 0.05). The rise in SST was significantly correlated with the rise in air temperature (p < 0.05), but not with precipitation. In the 2010s compared to in the 1981, catches of anchovy and squid greatly increased (p < 0.05), while catches of Alaska / walleye pollock has been almost extinct over the past 30 years. As such, cold-water fish species decreased or disappeared, and their fishing ground was replaced by warm-water fish species. Conclusions: These findings indicate that fish species caught in offshore fisheries of Korea have changed due to climate change, especially warming. This suggests that the warming of the Korean Peninsula may have a significant impact on the supply of fishery products and food security to Koreans in the near future.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.155-156
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• 2001

최근 수산물이 인체에 미치는 영양 및 건강효과로 어류소비량은 전세계적으로 매년 2.5％정도 증가하고 있으며 이중 양식어류가 26％을 차지하고 있고 수요량은 계속 증가 추세에 있다. 그러나 환경오염 및 각국의 경제수역 설정으로 어획량은 감소하고 있으며, WTO 출범 이후 세계적으로 자국의 자원량 확보나 미이용자원의 활용에 많은 심혈을 기울이고 있다. 양식생산량 증대와 더불어 양어사료 생산량도 계속 증가하고 있으며, 사료는 양식산업 경비의 30-50％를 차지한다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.83-84
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• 2001

최근 어장환경의 변화와 과다한 어획으로 연근해의 수산자원은 주요 어획종의 어획량이 감소하고 있는 추세를 보이고 있다. 이로 인하여 연근해 수산생물자원의 주요 먹이생물 이었던 새우류의 자원이 증가하고 있다. 이와 같은 새우류 자원증가는 남해안 어민들로 부터 이동성 구획어업인 새우조망어업 허가 신청이 급증하고 있으나, 아직 새우조망어업에 대한 연구는 전무한 실정으로 본 어업에 대한 전반적인 연구가 요구된다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.1
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• pp.41-48
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• 1993

Using the eight-year-working diaries($1984{\sim}1991$) of the fishing co-operative in Tonggui-ri, Cheju-do, as well as the records of consignment sale in the fish trust market as the corporate body in Aewol-up, the results have been analyzed as follows. 1. The monthly catch of Turbo cornutus was high from September through December, representing $58.2\%$ of the annual total catches. The maximum sustained yield(MSY) of this stock was estimated to be 2.5 tons. 2. The maximum sustained yields of Haliotis spp. and Sulculus sp. were estimated to be 800kg and 750kg, respectively. 3. The maximum sustained yields of Stichopus sp. and Octopus sp. were 500kg and 2, 500kg, respectively. 4. The total yield of Hizikia fusiforme has been decreasing a little and that of Gelidium sp. has been increasing. The total yield of Gelidium sp. in 1984 was about 5 times greater than that in 1990. 5. The daily catchability by divers have been high at thirties, and the individual mean working day of divers was 101 per year. 6. The consignment sale rates were $100\%$ each for Turbo cornutus, Hiziki fusiforme and Gelidium sp., $25.5\%$ and $61.1\%$ for Haliotis sp. and Stichopus sp. respectively, and $0\%$ each for Sulculus sp. and Octopus sp.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.300-301
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• 2003

갈치 (Trichiurus lepturus Linnaeus)는 우리나라 서해 및 남해, 동중국해, 발해, 일본 서부 및 류슈 연안 등 한국 주변 수역에 넓게 분포하는 난류성 저어어종이다. 우리나라 갈치의 주어장은 EEZ 설정 후 어장이 많이 축소되어 최근에는 흑산도, 제주도 인근의 서해남부 및 제주도 서방해역에서 근해안강망, 쌍끌이기선저인망, 대형트롤, 대형선망, 근해채낚기 등에 주로 어획된다. 우리나라 갈치의 어획량은 1970년대 초반에는 급격한 증가추세로 1974년에 17만톤으로 가장 많았으며, 이후 1977년에 7만톤 수준으로 떨어졌고, 1997년부터 다시 높은 수준으로 회복 되면서 1983년에 다시 15만톤의 어획을 기록하였다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.423-429
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• 2001

Prediction of the variation in annual biomass was conducted for the white croaker. Argyrosomus argentatus in Korean waters using leslie Matrix, based upon fishery data for the past 21 years and biological data, We used density-independent and density-dependent Leslie Matrix models. Similar parameters were estimated from two models except that the density-dependent model was influenced by the density effect variable, q(i,t), The eigenvalue of the white croaker population for the $1984\~1995$ period was estimated to be 0.8, indicating a declining pattern of the population. The survival rate of 0-th year class was calculated to be 0.00005. Based on the schedule of the age-specific survival rate and fecundity, the future biomass and catch was predicted for various levels of fishing mortalities (F), If F was set at 0.252/yr ($F_{35x}$) or 0.368/yr ($F_{0.1}$), the biomass and catch increased, and if F was set at 0.922 ($F_{current}$), the biomass and catch decreased, The fishing mortality at equilibrium was estimated to be 0.7/yr. Finally, the management strategy of the white croaker was discussed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.2
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• pp.153-165
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• 1995

The fluctuations of catches in set nets around Kyeongbuk Province, the eastern coast of Korea, were analyzed and investigated by on the values of CPUE(Catch Per Unit Effort per hauling), and composition of dominant species caught from 1985 to 1989. Annual CPUE values were fluctuated every year, but their trends were decreased year by year, When the values were evaluated by species, the trends of annual catches were shown decreasing in file fish(Auteridae), mackerel(Scomber japonicus), tuna(Thunnus Thynnus), rock fish(Sebastes schlegelid) and yellowtail(Seriola quinqueradiata), increasing in sardine(Sardinops melanosticta), jack mackerel(Trachurus japonicus), and herring(Clupea pallasi), and similar in squid(Todarodes pacificus) and cuttle fish(Sepiidae). The main fishing season evaluated by monthly CPUE was estimated from August to November with a little difference by regions : from August to November at Chukpyon and Kanggu, from September to November at Chuksan and Kampo, and August to December in Hupo. When the DPUE values were analyzed by species, the main fishing seasons were quite different by species. Mackerel, jack mackerel, tuna, yellowtail, and rock fish were caught mainly from September to October, file fish and squid from November to January, sardine from April to May, herring in May, and cuttle fish in April. Annual catches were shown highest level in file fish and revealed higher by sardine, jack mackerel, mackerel, squid, tuna, and yellowtail in order. But the highest catches among each species were different with seasons, and that from January to July was sardine, from November to December file fish. The main migrating seasons of file fish, mackerel, squid, tuna, and cuttle fish at Chukpyon were a little earlier than at other regions. Though the migrating seasons of jack mackerel and tuna were almost same in every regions, that of sardine were shown 3 month's difference according to regions. In the year when the warm currents were stronger than those of the normal year and their isotherms were formed from the north to south along the eastern coastal line, the annual fish catches in set net were show higher levels.

• Environmental and Resource Economics Review
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• v.31 no.4
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• pp.451-480
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• 2022

The Japanese Flying Squid (Todarodes pacificus) is a commercially important species in South Korea and the most popular species among consumers. However commercial catches of Japanese Flying Squid have been declining since 2000. In this study, we conducted a stock assessment to identify stock status. This study differed from previous studies in two aspects: a greater amount of available fishing effort data was used, and data from China, Japan, and Korea were included. A CMSY (catch-maximum sustainable yield) model was used to estimate MSY, biomass and exploitation with Bayesian state-space implementation of the Schaefer (BSS) model for the method of stock assessment, and evaluated the species by dividing into two groups, 'Korea' and ' Korea·China·Japan'. In all cases, Japanese flying squid biomass showed a general decreasing trend. Additionally, the biomass estimated for 2020 was lower than the biomass necessary to achieve the maximum sustainable yield. To manage Japanese Flying Squid effectively, it is necessary to strengthen the resource management strategies of individual countries and prepare a cooperative plan among countries.