• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.45 no.1
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• pp.22-33
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• 2009

Ecological risk assessment(ERA), developed in Australia, can be used to estimate the risk of target, bycatch and protected species from the effects of fishing using limited data for stock assessment. In this study, we employed the ERA approach to estimate risks to tunas, billfishes, sharks, sea turtles and other species by the Korean tuna longline fishery in the Western and Central Pacific Ocean using productivity and susceptibility analyses of the ERA based on low(<1.30), medium(1.30-1.84) and high risk(>1.84). Albacore, bigeye, yellowfin, skipjack and bluefin tunas were generally evaluated in the medium risk. The susceptibility of tuna species, however, had higher risks than the productivity. Billfishes were also at medium risk, while sharks were at high risk by the tuna longline fishery. The risk of productivity was generally high, because most sharks caught by the tuna longline fishery have high longevities, i.e., over 10 years, including ovoviviparous species. Susceptibility, which is related with the selection of fishing gear, was also high, because the longline fishery has no gear modifications to prevent bycatch of protected species. Not only target tuna species were influenced by the tuna longline fishery in the Western and Central Pacific Ocean, but also nontarget species, such as pomfret, mackerels rays, sea turtle were done. Ecosystem-based fishery assessment tools, such as productivity and susceptibility analysis(PSA), have the ability to provide broad scientific advice to the policy makers and stakeholders.

• Journal of Fisheries and Marine Sciences Education
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• v.9 no.2
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• pp.236-245
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• 1997

On the basis of the seven species of fish caught by fishing boats with two crewmen belonging to the Iwawada Fisheries Cooperative of Chiba Prefecture, the fishing boats were classified by species withhigh market values, and the results obtainedwere reclassified by discriminant function. As a result, the fishing boats were classified into four groups. These four groups are : G1 featuring themain catchesof yellowtailsand skipjack/tunas ; G2 yellowtails and squids ; G3 squids and skipjack/tunas, and G4 octopus and other miscellaneous specles. Furthermore, principal component analysis were carried out on fish catches of the seven species in terms of the value obtained from a catch from the scores of the first, second and third principal components. The results of analysis show that Groups G1, G2 and G3 assume identical fishing form, while only Group G4 asumes a different fishing form.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.4
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• pp.317-325
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• 2022

Korean tuna purse seine fishery in the Western and Central Pacific Ocean (WCPO) began to operate in earnest in the early 1980s. Since then, the total catch has shown an increasing trend and the target species are skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacare) and bigeye tuna (Thunnus obesus). Based on the operational data of Korean tuna purse seine fishery from 2016 to 2020, the catch rates of target species (skipjack and yellowfin tunas) were analyzed by operation time for set types (free school and FAD sets). In the case of the free school sets, they were usually made from sunrise to sunset, and the catch rate was high before and after sunrise for skipjack tuna and before sunset for yellowfin tuna. On the other hand, for the FAD sets, more than 90% of them were made just before sunrise, and there were few operations during the daytime. The purpose of this study is to examine whether there are differences in the catch rate of skipjack and yellowfin tunas by operation time and by school type for Korean tuna purse seine fishery in the WCPO, which could be helpful in understanding its fishing characteristics and providing useful information for developing the stock indices of the target species.

• International journal of advanced smart convergence
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• v.13 no.1
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• pp.122-128
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• 2024

This study delves into the unique transformation of South Korea's elderly population, distinctively termed 'Nomad Silver'. Characterized by individuals aged 65 and above who actively seek novel experiences and embrace new activities, this demographic shift signifies a departure from traditional perceptions of the elderly. The Nomad Silver cohort, distinguished by their significant economic influence and evolving needs, necessitates a tailored approach to healthcare services. This paper underscores the importance of comprehending both the fundamental biological needs and the personalized desires of the Nomad Silver, aiming to enhance their satisfaction and overall well-being. Hospitals, in response, should innovate their services to resonate with the emotional, psychological, and social facets of this age group. Consequently, the paper proposes a four-pronged strategy for hospitals to adapt: comprehensive healthcare provision, patient-centric service development, senior health education coupled with community engagement, and establishing a generational bridge hub. Furthermore, the paper posits that catering to the Nomad Silver not only promises substantial financial gains for hospitals but also fosters new business opportunities across various sectors.

• Korean Journal of Community Nutrition
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• v.13 no.1
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• pp.125-133
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• 2008

This study was carried out to compare bone density risk factors affecting women's BMD, and to examine the relationship age, lifestyle and dietary habits for bone health by physical measurement and questionnaires. The subjects of this study were 194 women living in the Seoul area. When the subjects were divided into normal and risk groups, BMD, height, weight, BMI, total body water, soft lean mass, fat free mass, protein, mineral, body-fat of normal group were much higher than those of the risk group. The breakfast eating rate of the normal group was much higher than that of the risk group, walking time was significantly longer and exercise was more (p < 0.05). The normal group had more frequent intakes of tunas, squid, radishes, the green parts of radish, cucumbers, carrots and Iucchinis, tomatoes, and grapes than the risk group (p < 0.01 or p < 0.05). In conclusion, breakfast eating, exercise, intakes of some foods such as anchovies, radishes, carrots, zucchinis and tomatoes were significantly important factor to prevent bone density risk.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.2
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• pp.185-190
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• 1998

The aim of this study was to develop the artificial trap baits being able to replace the natural anchovy or sardine baits. The fishing trials for evaluating the fishing efficiencies of the artificial baits were conducted with commercial traps at coastal areas near Tongyoung, southern Korea. The preferable artificial baits which were made of minced anchovy, sardine, mackerel, or fish surplus products mixed with wheat flour into dry or wet pelleted or crumbled types, were showed some merits as the following. \circled1 Fishing efficiencies of the artificial baits were same or little higher level than that of the natural bait anchovy; \circled2 bait cost were same or little lower level; \circled3 dry artificial baits stocked in the room condition showed good fishing efficiencies; \circled4 making of artificial baits were very simple; \circled5 there were no harm to the fish and little pollution to the environment; \circled6 the releasing rate of attractants in the artificial or natural bait showed similar patterns. The artificial baits using the fish by-products which were vacuum freeze-drying extract of boiled anchovy or tunas extract, showed lower catches in the conger eel, Coner miriaster, but similar catches in the crabs, mainly Charybdis japonica, to the those of natural anchovy bait.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.4
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• pp.356-362
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• 1996

In order to suggest the useful information of fishing ground, a data base system on 32bit personal computer was developed and handled by using the catch data of Korean tuna long -line. This data base system was programmed using Quick Basic, and consisted of three kinds of programs, one for displaying the catch rate on the fishing ground by fishing area and year ranges, another for indicating the catch rate or number on table or graph, and the other for estimating the fishing ground in economical points, mainly targeting total tunas, yellowfin and bigeye tuna respectively. When this system was started, the map of oceans such as the Pacific, the Indian and the Atlantic, is drawn on the monitor. And then the catch rates of all species and each one are indicated by the figured symbols on the sea divisions of$5^{\circ}$ space of latitute and longitude.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.42 no.4
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• pp.210-216
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• 2006

The circle hook experiments were conducted to compare the catch rates of target and bycatch species between J hook and circle hooks in the tuna longline fishery of the eastern Pacific Ocean between $1^{\circ}48'S-7^{\circ}00'S\;and\;142^{\circ}00'-149^{\circ}13'W$ from July 15 to August 12, 2005. In the target species group no significant differences among 3 types hook, between size 4.0 traditional tuna hooks(J-4) and size 15 circle hooks(C15), and between C15 and size 18 circle hooks(C18) were revealed, but significant differences were found between J-4 and C18. In the bycatch species group significant differences were found among 3 types hook, between J 4 and C15, and between J-4 and C18, but no significant differences were revealed between C15 and C18. Large circle hook(C18) had the lowest catch rate for tunas and for other fishes, and the small circle hook(C15) had lowest rate for billfishes and sharks. The length distributions for bigeye tuna are very similar for the 3 hook types. There were very slight differences in length size between hook types in the bycatch species.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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• pp.277-291
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• 2020

In order to understand characteristics on bycatch of Korean tuna purse seine fishery, especially operations associated with Fish Aggregating Device (FAD) in the Indian Ocean, we conducted analyses related to bycatch by school association type (unassociated school, FAD associated school and log associated school) using the data collected by scientific observers from 2016 to 2018. The FAD used by Korean tuna purse seine fishery in the Indian Ocean was a drifting FAD, which belongs to non-entangling FADs according to the category proposed by the International Seafood Sustainability Foundation (ISSF). The target species of Korean tuna purse seine fishery are skipjack, yellowfin and bigeye tunas, accounting for 99% of the total catch. The ratio of bycatch was 0.97% in total catch and the discard accounted for less than 1%, indicating that most catch was retained on board. In terms of bycatch ratio by school association type, it accounted for 0.12% for unassociated school, 1.09% for FAD associated school and 1.25% for log associated school. As for the catch proportion of shark species by school association type, it accounted for 0.01% for unassociated school, 0.11% for FAD associated school and 0.10% for log associated school, which showed that unassociated school type was the lowest to affect bycatch of non-target and shark species. Given the proportion of bycatch compositions, however, it is considered that FAD associated school of Korean tuna purse seine fishery has less caught bycatch species of non-target and shark, compared to other fleets operating in the Indian Ocean.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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• pp.299-315
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• 2020

Tuna fisheries were applied to an integrated ecosystem-based fishery risk assessment method using indexes of target species status, inhabited species in a target ecosystem, habitat quality and socio-economic benefit of affected fisheries. This study suggested more effective and efficient management measures to break away from traditional management methods, such as limitation of catch and fishing effort. The results presented that the objective risk index (ORI_S) on sustainability of bigeye and yellowfin tunas by purse seine fishery was estimated high due to the high catch ratio of small fishes. The ORIs of biodiversity (ORI_B) and habitat quality (ORI_H) of purse seine fishery were also estimated at a high level from using fish-aggregating devices (FAD). However, due to skipjack tuna's high catches, the ORI of socio-economic benefit (ORI_E) was estimated at a very low level. Due to the high bycatch rate, ORI_B was high, and ORI_S and ORI_H were evaluated at a low level in longline fishery. Due to strengthern of fishing restrictions and increase of fishing costs, the ORI_E was assessed to be very high. The ecosystem risk index (ERI) for two tuna fisheries was assessed low, but the overall FAD management by purse seine fishery is necessary at the ecosystem level.