• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.43 no.3
• /
• pp.176-182
• /
• 2007

Fishing power, which means performance of fishing vessel or catchability of fishing gear, can explain using by fishing power index(FPI) to compare fishery efficiency among uniformity types of fishery that work during the fixed period in specific fishing ground. This research analyzed on their fishing power and catchability using comparing each sampled vessels of coastal trap fishery for common octopus. The results showed that they were no difference in amount of used trap and immersed time etc. in CPUE among sampled vessels, and had no correlation of catch production due to vessel's tonnage. Most vessel's FPI estimates but 3 vessels were higher than the averaged, and showed similar fishing power in general. And then, CPUE and FPI showed that 4 to 5 tonnage vessels would be superior to another, 4 tonnage vessels had also good catchability. Therefore, we estimated that 4 tonnage vessels had the most efficiency work for coastal trap fishery for common octopus.

• Journal of Fisheries and Marine Sciences Education
• /
• v.10 no.2
• /
• pp.162-183
• /
• 1998

The fisheries resources control system in the Fisheries Act of Korea is introducing technical management method and input control method that controls fishing effort. Fishing effort control system of Korea aiming at realizing the maximum sustainable yield does not regulating the limitation of fishing quota and the limitation of fisheries object target fish. Therefore fishing operators who have fishing permit can use fishery resources without any restriction of fishing quota. But there are no rules that can controlling capacity of productivity of fishing by developing of fishing technic and fishing gear. For those reasons, productivity of fishing is superior to reproductivity of fisheries resources. Therefore, the Fisheries Act of Korea rearranges a legal basis for an introduction of fisheries resources management system by TAC, but the contents to be possible for a legal guarantee is not included and it is exceedingly defective as abstract and institutional devices. And that the affairs to be required for an enforcement of the said regime was placed in an administrative mandatory legislation and the danger to be degenerated is high in accordance with the bureaucratic self-righteous and/or the coercion of group's interest concerned and accordingly its substitute legislation system is keenly required. TAC system that is going to be introduced in our country is expected to enforce the Olympic fishing method and the individual quota method in parallel. This method is not certainly proper, because it occurs to overcapitalize and to compete fishing amounts between fishery operators. So as to prevent overcapitalization and fishing competition between fishery operators, and the exhaustion of coastal fisheries resources, individual transferable quota system should be introduced in Korean sea. Accordingly this thesis has attempted to constitute a view to improving problems of the traditional fisheries resources control system and introducing TAC fisheries resources control system.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.51 no.2
• /
• pp.171-178
• /
• 2015

Selectivity and by-catch are the main features used to define fish catch for fisheries management or to determine fishing gear efficiency. A fish girth distribution analysis was carried out to determine the retention rate of juveniles discarded and to establish common selectivity for a multispecies catch. Total body length, body weight, and girth of juvenile fish retained in the cod-end and cover net separately were collected using an 18-mm mesh cover net during 12 fishing trials with a 41-mm cod-end beam trawl. The by-catch weight ratio in the cod-end was twice that of the by-catch ratio in number. The 50% selectivity of body length and 50% girth of redfin velvet fish were not significantly different between the cod-end and cover net, whereas those of other fish species were significantly different between the cod-end and cover net. The difference in 50% selectivity girth of other fish between the cod-end and cover net was similar between cod-end mesh size and cover net mesh size. Furthermore, the difference in 50% body length selectivity of other fish between the cod-end and cover net was almost double the difference in girth. Girth selectivity in a multispecies catch using towed fishing gear was effectively used to determine fish and net mesh size.

• Fisheries and Aquatic Sciences
• /
• v.26 no.10
• /
• pp.617-627
• /
• 2023

Harvest control rules have been recently developed for some fisheries in Indonesia, including grouper fisheries, and are expected to reverse the trend of declining stocks. One of the proposed options of the harvest control rules is to implement the catch size limit. The catch size limit approach, however, is challenging, unless it is supported also with strong fisheries surveillance, law enforcement, and innovation. The catch size limit approach can be done by implementing changes in fishing methods and gear, including the application of different hook sizes in the hook and line fishing gear. This study examines the impact of different hook sizes on the length at first capture (Lc) and on the bell-shaped maximum selectivity using various selectivity models of the two targeted grouper species (Plectropomus leopardus and Plectropomus maculatus) in the Saleh bay, West Nusa Tenggara, Indonesia. We found that increasing hook size influences the grouper's catch size, increasing the Lc and the bell-shaped maximum selectivity of both species. Based on our findings, hook size can be used as one of the practical tools for grouper management measures, as part of harvest control rules to improve grouper stock in Indonesia.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.60 no.2
• /
• pp.170-178
• /
• 2024

This study aimed to quantitatively analyze the risk using data from 329 safety accidents that occurred in aquaculture fisheries management vessels over the recent five years (2018-2022). For quantitative risk analysis, the Bayesian network proposed by the International Maritime Organization (IMO) was used to analyze the risk level according to the fishing process and cause of safety accidents. Among the work processes, the fishing process was analyzed to have the highest risk, being 12.5 times that of the navigation, 2.7 times that of the maintenance, and 8.8 times that of the loading and unloading. Among the causes of accidents, the hull and working environment showed the highest risk, being 1.7 times that of fishing gear and equipment, 4.7 times that of machinery and equipment, and 9.4 times that of external environment. By quantitatively analyzing the safety accident risks for 64 combinations of these four work processes and four accident causes, this study provided fundamental data to reduce safety accidents occurring in aquaculture fisheries management vessels.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.56 no.1
• /
• pp.37-44
• /
• 2020

The change of fishing power index was analyzed to identify the development of the vessel and gear technology that may improve the fishing efficiency of the offshore conger eel pot fishery from 1980s to 2015. Gross tonnage per fishing vessel was rapidly increased annually. The standard of pot was maintained, but the number of pot used rapidly increased by using conger eel pot hauling devices, carrying and loading devices, main line hauler, casting devices and slide type pot. Fish finder system to identify fishing ground information and the conger eel pot hauling devices were modernized, and supply rate was also increased. Therefore, the relative fishing power index in the offshore conger eel pot fishery increased from 1.0 in 1980 to 1.3 in 1990, to 1.8 in 2000 and to 2.0 in 2015. The results are expected to contribute to reasonable fisheries stock management of the offshore conger eel pot fishery.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.55 no.2
• /
• pp.145-151
• /
• 2019

The coastal composite fishery has the highest rate of around 30.0% in registered fishing vessels of Korea for the last three years. The risk analysis for the fisher's safety of coastal composite fishing vessels was conducted to serve as a basic data for improving the healthy and safe working environment of fisher using fisher's occupational accidents of the national federation of fisheries cooperatives (NFFC) from 2016 to 2018 (n = 1,105). As a result, the occupational accident occurrence rate of coastal composite fishery was 3.76% in all industries, 7.8 times the rate of that. In addition, death and missing rate was found to have a serious level management to 10.10‱. Among the accidents, 76.0% occurred at sea. The slipping, others and contact with machinery or fishing gear occurred more frequently in order in the frequency of accident occurrence pattern. In the risk assessment using frequency and severity, slipping, contact with machinery and others showed high risk during fishing. The results are expected to contribute to identification and assessment of safety hazard occurred in coastal composite fishing vessels.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.59 no.2
• /
• pp.99-109
• /
• 2023

In this study, a comparative test operation was conducted through the alternate haul method to examine the selectivity of the four mesh sizes (60 mm, 90 mm, 110 mm, and 130 mm) of the trawl codend. The selectivity was analyzed using the SELECT model considering the fishing efficiency (split parameter) of each fishing gear in the comparative test fishing operation in the trawl and the maximum likelihood method for parameter estimation. A selectivity master curve was estimated for several mesh sizes using the extended-SELECT model. As a result of analyzing the selectivity for silver croaker based on the results of three times hauls for each experimental gear, it was found that the size of the fish caught increased as the size of the mesh size increased. When the selectivity for each mesh size analyzed by the SELECT model considering the split ratio was evaluated based on the size of the AIC value, the estimated split model was superior to the equal split model. Based on the master curve, the 50% selection length value was 2.893, which was estimated to be 136 mm based on the mesh size of 60 mm. In some selectivity models, there was a large deviance between observed and theoretical values due to the non-uniformity of the distribution of fished length classes. As a result, it is considered that appropriate sea trials and selectivity evaluation methods with high reliability should be applied to present trawl fishery resource management methods.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.53 no.3
• /
• pp.219-227
• /
• 2017

In pelagic longline, deploying the gear such that the depth of the hook is the same as that of the target fish is important to improve the fishing performance and selectivity. In this study, the depth of the tuna longline hook was estimated using the mass-spring model, catenary curve method, and secretariat of the pacific commission Pythagorean method in order to improve the performance of the longline gear in Fiji. The former two methods were estimated to be relatively accurate, and the latter showed a large error. Further, the mass-spring model accounted for the influence of tidal current in the ocean, which was found to be appropriate for use in field trials.

• Journal of Fisheries and Marine Sciences Education
• /
• v.14 no.2
• /
• pp.191-212
• /
• 2002

The economic and social bad influences of the illegal fishery bring about the results of the fishery resources exhaustion, of the fishery disorder and of the obstruction to sound management for fishery. The typical illegal fishery conducted in the coastal and offshore area of Korea can be divided as follows; fishery conducted by legally unauthorized method, fishery without permission from the Government, and fishery conducted in contravention of the laws and regulations concerning the fishing vessel, fishing gear and fishing method etc. The major reasons of origination of the illegal fishery in the coastal and offshore area of Korea are; Firstly, almost of the fishermen are poorly equipped in economical scale, Secondly, it is very easy to approach the illegal fishery because the domiciliation condition of the fishing village is deteriorated. Thirdly, almost of the fishermen are lacking in lawabiding spirit. Fourthly, the insolvent and unstable fisheries management policy with the lukewarm enforcement of the fisheries laws and regulations by the Government. Fifthly, the small scale family supporting fisheries are widespreaded. Sixthly, to retrieved the economical difficulties the fishermen are easily led astray the illegal fishery. As a conclusion the authors made some suggestions to stamp out the illegal fishery by this study. For the first, temptation fishermen into lawabiding fishery through intensification of the penal regulations is required. Second, simplification of the fishery type through combination of resemble fishing methods is required. Third, actual improvement of the fundamental fishery permission regime is required. Fourth, Introduction of the self-regulating or co-management system for the fishery management is required.