• The Journal of Fisheries Business Administration
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• v.38 no.1 s.73
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• pp.71-96
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• 2007

This study is aimed to investigate how the structure of Korean and Chinese fisheries has been changed since the Fisheries Agreement between Korea and China came into effect. This investigation was accomplished from a comparative point of view by using statistic data in the literatures published by both Korea and China. Results of this study are summarized as follows; First, it was revealed that the decreasing rate of fish production of marine capture fisheries in Korea was lowered more by 5.1%, while it was decreased by only 0.1% in China. Second, comparative results on changes in production of offshore fisheries showed that the production of Korean offshore fisheries in 2003 was reduced by 26% compared to that in 1999, while the production of China offshore fisheries was decreased by 22%. In addition, although the production of marine capture fisheries in the East region of China was reduced by 10%, on the contrary, the production of marine capture fisheries in Liaoning, Hebei, Tianjin, Jiangsu, Zhejiang, and Fujian that have mostly impacted by the Korea-China Fisheries Agreement was increased by 7%. Third, results on fishing capacity of marine fisheries indicated that the number of vessels and total horse power in Korea were increased by 1.2% and 44.9%, respectively, while total tonnage was reduced by 23.9%, For China, the number of vessels and total horse power were increased by 0.5% and 12.6%, respectively. Total tonnage was also increased by 11.7%. Finally, the production per Korean vessel was decreased by 17.8% in 2003 compared to that in 1999. On the contrary, the production per Chinese vessel was increased by 8.1% in 2003. The production per tonnage was increased by 3.2% in Korea, while it was reduced by 2.7% in China. In conclusion, it could be said that the Korea-China Fisheries Agreement has had a positive impact on the fisheries production of China, while it has had a negative impacts on that of Korea, relatively.

• Ocean and Polar Research
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• v.39 no.4
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• pp.301-318
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• 2017

The production of Korean offshore fisheries has been gradually decreasing due to the severe depletion of offshore fisheries resources caused by excessive fishing efforts. The production of the offshore fisheries in 2016 was the lowest since 1975. So the federal and local governments in Korea adopted and implemented various fisheries management plans and policies in order to restore fisheries resources. However, these plans and polices have not been successful in re-establishing fisheries resources. Thus, in order to accurately diagnose the situation with regard to offshore fisheries, this study sought to estimate not only the return to scale by fishing gear of offshore fisheries, but marginal productivity of individual fishing gear based on production factors derived from offshore fisheries production functions. The study was organized in the following manner. First of all, this study estimates production functions of offshore fisheries. The Cobb-Douglas and the translog production functions are adopted as offshore fisheries production functions. Specifically, the functions are estimated by crew, vessels, and offshore resource as production factors. The offshore resource is estimated by the Clarke Yoshimoto Pooley model based on the surplus production model. Secondly, the fisheries production functions are extended to the fixed-effect model and the random-effect model with panel data. Thirdly, this study analyzes the return to scale of offshore fisheries and the marginal productivity of the production factors from the estimated offshore fisheries production function. In conclusion, this study suggests plans and countermeasures for productivity improvement by group (labor intensive or technology intensive) based on the characteristics of individual offshore fishing gear.

• The Journal of Fisheries Business Administration
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• v.44 no.1
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• pp.15-24
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• 2013

Recently the Korean court accepts two typies of fisheries damages caused by oil pollution.. One is the direct loss of fisheries production originated from pollution of oil spillover. The other is the indirect loss of fisheries production originated from governmental measure of restricting fishing activities because of safety of marine product of oil spillover areas. The paper tries to suggest the appropriated measure of oil pollution damages of hanging and floating netcage aquaculture fisheries using the court judgement for responsibility restriction on Herbei Spirit Case. The paper tries to compare the damge estimation method of floating netcage aquaculture fisheries with that of natural aquaculture fisheries using conventional theory of the population biology of living resources characterized with age distribution.

• The Journal of Fisheries Business Administration
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• v.45 no.1
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• pp.109-119
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• 2014

This study aimed to examine the applicability of a portfolio approach to the ecosystem-based fisheries management targeting the large purse seine fishery. Most fisheries are targeting multispecies and species are biologically and technically interacted each other. It enables a portfolio approach to be applied to find optimal production of each species through expected returns and risk analyses. Under specific assumptions on the harvest quota by species, efficient risk-return frontiers were generated and they showed a combination of optimal production level. Comparisons between portfolio and actual production provided a useful information for targeting strategy and management. Results also showed the possibility of effective multispecies fisheries management by imposing constraints on each species such as total allowable catch quotas.

• Fisheries and Aquatic Sciences
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• v.24 no.4
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• pp.139-152
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• 2021

The main purpose of this study is to fit catch-per-unit-effort (CPUE) data about Korea chub mackerel (Scomber japonicus) stock with a state-space production (SSP) model, and to provide stock assessment results. We chose a surplus production model for the chub mackerel data, namely annual yield and CPUE. Then we employed a state-space layer for a production model to consider two sources of variability arising from unmodelled factors (process error) and noise in the data (observation error). We implemented the model via script software ADMB-RE because it reduces the computational cost of high-dimensional integration and provides Markov Chain Monte Carlo sampling, which is required for Bayesian approaches. To stabilize the numerical optimization, we considered prior distributions for model parameters. Applying the SSP model to data collected from commercial fisheries from 1999 to 2017, we estimated model parameters and management references, as well as uncertainties for the estimates. We also applied various production models and showed parameter estimates and goodness of fit statistics to compare the model performance. This study presents two significant findings. First, we concluded that the stock has been overexploited in terms of harvest rate from 1999 to 2017. Second, we suggest a SSP model for the smallest goodness of fit statistics among several production models, especially for fitting CPUE data with fluctuations.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.1
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• pp.115-131
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• 2005

The fishery buy-back programs were studied to analyze fishery production and CPUE. The results from this study during the concerned period can be derived as follows: 1. In total offshore fisheries, CPUE for each boat increased 8.7%, and 8 fishing categories were increased in CPUE for each boat. CPUE for tonnage increased 4.2% in total offshore fisheries field, and 7 fishing categories increased in CPUE for tonnage. In total offshore fisheries, CPUE for HP increased 6.8%, and 8 fishing categories increased in CPUE for HP. 2. The correlation coefficient of the number of fishing boats vs. production and that of the tonnage vs. production were 0.91. This means that there is a strong relation between them. The correlation coefficient of the number of fishing boats vs. CPUE for each boat and that of the tonnage vs. CPUE for tonnage were -0.73 and -0.88 respectively. This reveals that there is a relatively strong reverse relation between them.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.235-240
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• 2015

Seasonal variation in the prevalence of norovirus in oysters Crassostrea gigas was investigated and compared to levels of Escherichia coli, a fecal indicator in oysters. Oysters were collected from Iwon-myeon, Taean-gun, Korea, a primary production area for European Union export of oysters between 2013 and 2014. We observed seasonality in the prevalence of norovirus in oysters, with a higher prevalence and viral load detected during winter months. Oysters taken from production areas that complied with the European Union standard for raw consumption (< 230 MPN/100 g of E. coli) had 22.1% of the samples test positive for norovirus (15/68 samples). However, norovirus was not detected in any of the samples (0%, 0/4 samples) that were collected from production sites that exceeded the standard fecal contamination level for raw consumption (> 230 MPN/100 g of E. coli). These results indicated that there is a negative correlation between the prevalence of norovirus and high levels of E. coli in oysters. Therefore, our results suggest that current food safety guidelines using only a bacterial fecal contamination indicator, E. coli, may not adequately assess shellfish production areas for viral and bacterial contamination.

• The Journal of Fisheries Business Administration
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• v.51 no.1
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• pp.19-36
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• 2020

The purpose of this paper is to analyze the productivity of the costal fisheries in Jeonnam Province. In this study, the operational characteristics and Cobb-Douglas production function of coastal fisheries were examined based on a research on the actual condition of costal fisheries (RACF). The statistical analysis of RACF data reveals that Cobb-Douglas production function consists of the three variables: fishing quantity per ton-age, the number of fisherman per ton-age and fishing equipment cost per ton-age. The results of this study show us that the relation and productivity between labor and capital of the operational equipment in the coastal fisheries. If extensive comparable biological and market data become available, analysis model can be widely applied to yield more accurate results.

• Journal of Fisheries and Marine Sciences Education
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• v.19 no.1
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• pp.150-160
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• 2007

The school system of fisheries high school was proper to specialist objective school system in order to training for expert human resource development.Training a field of human resources development from fisheries high school is fallow; fisheries production, seamen's training, ship engine and refrigerator, marine electronic telecommunication and information, fisheries foods production and fisheries foods production and distribution, fishery fisheries self-management, marine distribution, management and conservation of marine environment, safety and marine prevention of disasters, apparatus of marine development, under water area development.A new department opening and each department was revised toward to department name and department character. The unit-lesson hour of curriculum according to specialist objective school system of fisheries and marine highschool was revised. professional subject 98 unit-lesson hour(52%), normality subject 90 unit-lesson hour(48%), and educational activity of professional subject 10unit-lesson hour, total training activity 10 unit-lesson hour. And the special objective school system need to revise curriculum of 208 total unit-lesson hour.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.2
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• pp.124-137
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• 2018

Due to the decrease in coastal productivity and deterioration in the quality of ecosystem which result from the excessive overfishing of fisheries resources and the environmental pollution, fisheries resources in the Korean waters hit the dangerous level in respect of quantity and quality. In order to manage sustainable and effective fisheries resources, it is necessary to suggest the potential yield (PY) for clarifying available fisheries resources in the Korean waters. So far, however, there have been few studies on the estimation methods for PY in Korea. In addition, there have been no studies on the comparative analysis of the estimation methods and the substantial estimation methods for PY targeted for large marine ecosystem (LME) For the reasonable management of fisheries resources, it is necessary to conduct a comprehensive study on the estimation methods for the PY which combines population dynamics and ecosystem dynamics. To reflect the research need, this study conducts a comparative analysis of estimation methods for the PY in the Korean waters of the East Sea to understand the advantages and disadvantages of each method, and suggests the estimation method which considered both population dynamics and ecosystem dynamics to supplement shortcomings of each method. In this study, the maximum entropy (ME) model of the holistic production method (HPM) is considered to be the most reasonable estimation method due to the high reliability of the estimated parameters. The results of this study are expected to be used as significant basic data to provide indicators and reference points for sustainable and reasonable management of fisheries resources.