• Journal of Ocean Engineering and Technology
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• v.15 no.1
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• pp.36-44
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• 2001

To predict the influence on fish stocks which were caused by environmental change in the fishing ground of shallow sea areas, we have developed the Shallow-Sea Ecological Model(SSEM) which that focuses on living organisms, especially fish and benthos. By applying the SSEM in the Seto-Inland Sea of Japan, we have simulated another aspect of influence on fish stocks that was caused by oxygen deficient water mass and nutrient loads. From the simulated result of the fish stocks, it was indicated that the stock of fish and benthos has shown a relative difference between the western sea and the eastern sea in the Seto-Inland Sea. According the to prediction, results of fish stocks that were caused by oxygen deficient water mass, it was estimated that the pelagicfish stock increases about 6 %, whereas the stocks of demersalfish and benthos decreases about 30% and 70%, respectively. On the other hand, it seemed that there was an increased in the fish stocks of demersalfish and benthos in the eastern sea of Seto-Inland Sea by nutrient loads reduction.

• The Journal of Fisheries Business Administration
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• v.40 no.2
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• pp.71-103
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• 2009

This study is designed to propose the ways of the multilateral cooperation system for effective management of fisheries resources in the various overlapping zones established by bilateral fisheries agreements between Korea, China and Japan in North East Asia as semi-enclosed sea. It is necessary to build multilateral fisheries cooperation between Korea, China and Japan in North East Asia because conservation & management of transboundary fish stocks could not be guaranted effectively by the management of fisheries resources in the area where piled up the current-fishing-pattern zone, as white zone and the various grey zone as middle zone, and the interim measures zone of bilateral fisheries agreements between Korea, China and Japan are piled up. Fisheries management in Korea, China and Japan by the bilateral fisheries agreements in North East Asia is faced with difficulties manage fisheries resources. International relationship on fisheries is maintained by bilateral fisheries agreements based on UNCLOS. However fisheries resources are over-exploited and the recovery of the fisheries resources is very slow because proper conservation and management of transboundary fish stocks which article 63(1) of UNCLOS defines have not prepared yet. Thus close cooperation among the coastal States for a proper conservation and management of transboundary fish stocks is necessary. Since the transboundary fish migrate within the EEZs of two or more coastal States, there is a need to manage the fish stocks in the region between Korea, China and Japan through a multi-lateral mechanism at ccircumference area of the current-fishing-pattern zone as white zone. Coastal States must guarantee sustainable maintenance of transboundary fish stocks through the regional cooperation for a proper conservation & management because one coastal State alone could not guarantee conservation and management of fish stocks. Thus there is a need to build multilateral fisheries cooperation between Korea, China and Japan in North East Asia. There are many successful instances including the Barents' sea for a proper conservation & management of transboundary fish stocks. The Barents' sea is one of the best research object to study the regional cooperation for a conservation & management of transboundary fish stocks in North East Asia. In conclusion, it is necessary to build a multilateral fisheries cooperation system between Korea, China and Japan in North East Asia to conserve and manage transboundary fish stocks effectively. It seems desirable that the range of the area to conserve and manage fish stocks should may be any partial area in the current-fishing-pattern zone and interim measures zone between Korea and China, Jeju middle zone between Korea and Japan, interim measures zone of bilateral fisheries agreements between China and Japan.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.238-256
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• 2004

As the UN Fish Stocks Agreement has come into effect since 2001, the actual enforceable management on fish stocks in high seas has started. The Regioanl Fisheries Organizations (RFOs) have emerged as management bodies with a real responsible right to manage fish stocks. RFOs establish a strong and strict management rules providing a fishing right only to member countries and preventing all fishing activities from fishing vessels of non-member countries. In addition, RFOs have an own allocation way of fishing opportunity in their waters so that they can prevent the depletion of fish stocks. It is investigated that deep-sea fisheries have a negative impact from strengthening of RFOs' management right. As the amount of catch is reduced by the control of fishing vessel's activities, the level of fishing revenue becomes low. Moreover, as fishing costs such as oil, fishing fees, labor cost increase significantly, the condition of fishing business is getting worse as a result. In order to gain a fishing right for deep-sea fishing vessels in RFOs waters, there is no other alternative way but become a member of RFOs which are relevant to our fisheries but not joined.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.475-483
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• 1990

An assessment of Kuwait's commercial fish stocks: hamoor (Epinephelus tauvina), zobaidy (Pampus argenteus), nakroor (Pomadasys argenteus) and sheiry (Lethrinus nebulosus), was conducted using length-frequency data, mean growth and mortality estimates obtained during 1981$\~$1988. The length-cohort analysis indicated that increases in fishing effort would not lead to long-term gains in yield of the stocks at the current estimate of natural mortality rate (M). At high M which was assumed arbitrarily, some benefit in yield could be obtained, especially for hamoor and sheiry. At low M, the yield of all stocks decreased with increased fishing effort. Increases in fishing effort resulted in significant dec-line in spawning stock size for all the stocks. Yield-per-recruit analysis indicated that, un-der low M assumption, a higher yield can be obtained for zobaidy and nakroor by reducing fishing effort. At moderate M, decreases in fishing effort brought gains in yield per recruit of the stocks, but it was not substantial compared with the present level of M. At high M, most of the stocks reached the maximum yield-per-recruit. Overall, increased fishing effort either will not be associated with large long-term gains in yield or, in some stocks, might cause a decline from the present level.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.3
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• pp.388-401
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• 2010

This research aims at analyzing impacts of climate change on fisheries. Climate change is an additional pressure on top of the many which fish stocks already experience. This implies that the impact of climate change must be evaluated in the context of other anthropogenic pressures, which often have a much greater and more immediate effect. Conversely, it is evident that fish stocks will be more resilient to climate impacts if the stresses due to other factors, such as over-fishing and pollution, are minimized. Improved management of fisheries and of marine ecosystems can undoubtedly play an important role in adapting to the impacts of climate change. Most of the improvements which are needed do not require new science or understanding, they require patient development of acceptable, effective, responsive social institutions and instruments for achieving adaptive management. Management advices must include complete and transparent information on risks and uncertainties which arise from data quality and from structural deficiencies in the assessment models. Well-designed and reliable monitoring of fish stocks and the marine ecosystem is essential in order to detect changes and give warning in advance of alterations in the productivity of individual species and of the structure and functioning of the ecosystem and fishery economy on which they depend.

• Journal of fish pathology
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• v.13 no.1
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• pp.53-59
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• 2000

Presence of marine birnavirus (MABV) was examined against egg and ovarian fluid, and seminal fluid from the brood stocks of flounder, Paralichthys olivaceus collected from 9 different stations around Korean peninsula. The detection rate of MABV in brood stocks flounder was observed to 34% by PCR. The mean virus titer of the PCR positive fish was $10^{2.30}$ to $10^{4.30}$ $TCID_{50}$/g(ml). By a neutralization test, all of the isolated virus were ascertained to be closely related to marine birnavirus (MABV).

• The Journal of Fisheries Business Administration
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• v.49 no.3
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• pp.49-65
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• 2018

The main purpose of this study is to explain fishery relation in the seas surrounding Korea and how the Prisoner's Dilemma (PD), within game theory is applied to the region and suggest possible co-operative approaches in the region. The seas surrounding Korea are very productive fishing grounds with abundant fisheries resources because of the favourable marine environment, including its geographical features and physical oceanography. Nevertheless, Fishery relations among the coastal states in the region have been historically characterized by conflict rather than co-operation. Based on the PD game where there is always an incentive to do better by not co-operating, in order to ensure a share of the short-run benefits, fishing countries in the region have so far pursued the non-co-operative strategy of 'don't fish responsibly' rather than the co-operative strategy of 'fish responsibly'. Considering rapidly deteriorating situations in terms of fishery resources, regional co-operation among coastal states is urgently required to eliminate overfishing and increase fish stocks to sustainable levels. The West Sea/East China Sea and the East Sea, semi-enclosed seas, have unitary ecosystems, and many migratory fish species are shared between coastal states. Therefore, one countries' efforts alone cannot effectively manage and conserve the fishery resources and close co-operation among coastal states is required. The 1982 UN Convention and other international instruments emphasize the role of RFOs in managing and conserving capture fisheries and encourage states to establish Regional Fishery organizations (RFOs) or strengthen existing RFOs to facilitate conservation and management for fish stocks. Therefore, an international regime is worthy of serious consideration in that it provides fundamental advantages for the conservation of fish stocks for the fishery characteristic of the region.

• The Journal of Fisheries Business Administration
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• v.34 no.1
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• pp.137-156
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• 2003

Increasingly, leisure time is being used for outdoor recreational activities, and fishing is one of the principal forms of marine recreation. Marine recreational fishing is a popular activity in Korea and this activity has led to the development of a sector of substantial social and economic value. Also it is considered as one of the important outdoor leisure industries in Korea. With rising of income level and development of marine outdoor leisure industries, social, economic demand increase of marine recreational fishing are showing us new advance ability of marine aquatic bio-industry. However the recreational use of fish stocks has become an important consideration in the public and environmental economic analysis of management aspect of fishing, having grown considerably over recent years to reach a level in Korea where the fish stocks and coastal ecosystem has become a significant management problem. we are inevitably facing marine environmental deterioration and overfishing in marine recreational fishing. In this study, not only resources and environmental problems which are occurred by recreational fishers, but also illegal fishing behaviors and other problems such as market's failure are going to analyze basic management theories and methods of recreational fishing through mathematical principals and economic rents which maximize net social benefits. In view of the likelihood of marine recreational fishers adopting high rates of discount, the conservation of fish resources would appear to require continual public surveillance and control of the physical yield and condition of the fish stocks and the optimal use level. The institutional management of recreational fisheries is the way of escaping the collapse of recreational fisheries just like as the situation of management's failure of commercial fisheries worldwide. One of the effective management measure is a license system. In this system, optimal fee is paid by recreational fishers, which prevent them from overfishing, environmental problems to some extents and carry out the optimal number of outings. And money obtained by license fee should be spent for more improvement fishing culture and welfare for marine recreational fishing. Marine recreational fishing is to be promoted under sound conservation and management principles.

• Journal of Fisheries and Marine Sciences Education
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• v.19 no.1
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• pp.53-73
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• 2007

There exists historically intimate relationship between the fisheries of the three countries of Northeast Asia in terms of the same fishing ground and similar resources. This means that if one of the countries fail to manage their fisheries properly, it will harm the others. Especially, if the EEZ straddling and Trans-Boundary Fish Stocks aren't managed by the cooperation of the three countries, the exhaustion of resources will be more likely to be accelerated. Considering the aspects mentioned, this paper refers to the necessity of fisheries cooperation between Korea, China, and Japan. Next, it analyzed the joint control cases of Norway/Russia Management of Shared Fish Stocks in the Barents Sea, Management of South Tasman Rise in Orange roughy, Agreement on Fisheries between the European Economic Community and the Kingdom of Norway, Conservation and management of pollack resources in the central Bering Sea, and drew a conclusion for ourselves. Last of all, it suggests a step-by-step strategy of promoting joint control between three countries, and the plan of the establishing and managing the organization of joint fisheries control. About the joint control, "The Joint Statement of promoting collaboration between Korea, China, and Japan" has been announced at ASEAN in October 7th, 2003 and the summit talk of the three countries. In the joint statement, the three countries came to an agreement which says, "Cooperation in Fishery Resource Conservation : The three countries will cooperate, bilaterally or trilaterally, to promote the sustainable use and conservation of fishery resource through the effective fishery management". Not only the consistent collaboration between the government is necessary, but also continuous exchange and related study on a Non-governmental level is also needed for the viable outcome in the near future. When deducting the result for the joint fisheries control, this writer hopes the contents of this study will be helpful.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.3
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• pp.266-272
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• 1996

The distribution and abundance of fish in the Cheju southeastern area was studied by the combined hydroacoustic and bottom trawl surveys in April 1994 and in July 1995, respectively. The main purpose of these investigations was to provide the basic data for this management and the biomass estimation of commercially important demersal fish stocks in this area. The hydroacoustic surveys were performed by using a 50 kHz scientific echo sounder system with a microcomputer-based echo integrator. Acoustical measurements of fish abundance and distribution were conducted along the cruise tracks of research vessel and during all trawl hauls by continuous echo sounding. The average weight-normalized target strength for demersal fish aggregations was derived from the relationship between the mean volume backscattering strength for the depth strata of trawl hauls and the weight per cubic meter of trawl catches. The geographical distribution of fish stocks in the 1994 survey area was investigated in relation to oceanographic conditions. The results obtained can be summarized as follows: 1. From the 1994 and 1995 survey data, the relationship between the mean volume backscattering strength (, dB) for the depth strata of trawl hauls and the weight (W, kg/$m^3$) per cubic meter of trawl catches was expressed by the following equation = - 32.8+ lOlog(W) The average weighted-target strength value at 50 kHz derived from this equation was .. 32.8 dB/kg. 2. In 1994 and 1995, both surveys showed a trend of decreasing fish abundance toward the southern area of the Cheju Island with high densities offish along the west coast ofth.e Tsushima Island. The highest demersal concentrations in the southern area of the CheJu Island appeared in bottom waters colder than $12^{\circ}C.$. . 3. From the results of combined bottom trawl and hydroacoustic surveys, the estunated fish densities in the southeastern area of the Cheju Island were 1.5488 x $10^-4$kg/$m^3$ in the 1994 surveyand 1.9498 x $10^-4$kg/$m^3$ in the 1995 survey, respectively.