• 한국수산과학회지
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• 제55권2호
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• pp.183-188
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• 2022

It is a difficult task to estimate parameters in even a simple stock assessment model such as a surplus production model, using only data about temporal catch-per-unit-effort (CPUE) (or survey index) and fishery yields. Such difficulty is exacerbated when time-varying parameters are treated as random effects (aka state variables). To overcome the difficulty, previous studies incorporated somewhat subjective assumptions (e.g., B₁=K) or informative priors of parameters. A key is how to build an objective joint prior of parameters, reducing subjectivity. Given the limited data on temporal CPUEs and fishery yields from 1999-2020 for common squid Todarodes pacificus, we built a joint prior of only two parameters, intrinsic growth rate (r) and carrying capacity (K), based on the resilience level of the population (Froese et al., 2017), and used a Bayesian state-space production assessment model. We used template model builder (TMB), a R package for implementing the assessment model, and estimating all parameters in the model. The predicted annual biomass was in the range of 0.76×10⁶ to 4.06×10⁶ MT, the estimated MSY was 0.13×10⁶ MT, the estimated r was 0.24, and the estimated K was 2.10×10⁶ MT.

• ALGAE
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• 제24권4호
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• pp.231-238
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• 2009

The genus Grateloupia is the largest with more than 96 currently recognized species in the family Halymeniaceae, but morphological features of the genus are highly homoplasious making species identification difficult. In this study, we analyzed rbcL gene from 34 samples collected in Korea and compared the haplotypes of Korean species with those already published. The rbcL tree confirmed the occurrence of eight species in Korea: G. asiatica, G. catenata, G. divaricata, G. elliptica, G. imbricata, G. lanceolata, G. subpectina, and G. turuturu. All, except G. asiatica and G.catenata, been introduced from their native northeastern Asian waters to Australasian, European, and North American waters. The introduced haplotypes of G. lanceolata in Europe and North America were absent in Korea, while haplotype sharing of G. turuturu in Korea and Europe was common. Further sampling will show a source population of each introduced species and also provide a correct list of Grateloupia from Korea, including the other remaining 11 species of the genus.

• 수산경영론집
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• 제5권1호
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• pp.9-42
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• 1974

Korea is a peninsular country surrounded by seas on three sides, and the fishing industry has carried out the service of suppling to the people with important anima protein. The distribution of fishery products has very complicated structures, because the production is in charge of small producers scattering along the coast all over the country, while consumpstion is made by separate homes in areas away from producing district. The relation between these two factors the structures make very complicated. The most typical and special structures of fishery distridution are distinguished in two, that is, one is landing market, the other is inland market. Landing markets have been monopolized by fishermen's cooperatives, providing with landing facilities and building sites. Fish markets played not only an important role in the landing, but distribution and price determination of catches by auction or tender. Inland markets are two types of wholesale market in consuming center, one is the terminal market for urban consumers, the other type is the local market for rural consumers. Fundamental functions of landing markets are gathering, assessment, and distribution functions. Gathering function is in charge of wholesaler in fishery cooperative. Gathering amounts are equal to gathering capacity of wholesaler and transact ability of licensed dealers as shown below model. Gathering amount=f.gathering capacity(=pre price.landing facility.account of wholesaler.distance of fishing ground.conveniency purchasing.home port)=fㆍ transact ability of licensed dealers≒f.population or port, and table 1 indicates these relationship. Assessment and distribution functions are in charge of licensed dealers in consumption side. Assessment function should bring the value in production activity through the auction between the cooperative seller and the licensed dealer as buyer. For fair trade transaction in auction, the free competition is supposed to be a prerequisite among the licensed dealers. The ideal condition for free competition is sameness in the scale of buying amount by licensed delaers, but it is almost impossible to attain its goal in actual marketing.

• 수산경영론집
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• 제29권1호
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• pp.27-63
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• 1998

This paper focuses on the history of fisheries finance in Korea, especially the role of fisheries finance after the establishments of korean fisheries cooperative. We can say that our fisheries was influenced greatly by the fisheries finance. It may be preyed by the facts that our fisheries experienced a great growth right after the input of big fisheries finance. The products of fisheries has increased from 1962 to now And the structure of the fisheries has improved. But there were unequal development in the each sectors of fisheries. Though the deep sea fishery and farming has developed faster, coastal fishing that are absorbing nearly 90% of fisheries population has stagnated. Of course it was because of unequal financial assistance by Authority. So to improve fisheries evenly, it is very important to overcome various problems that have encountered including the new circumstances like the WTO. For this, lots of steps should be taken. They can be summarized as follows. 1) It may be inevitable to see a rising costs in the deep sea fishery because of the declaration of EEZ by almost every nation. 2) So coastal fishing should be getting more important. It is necessary to improve the structure of coastal fishing and we should be ready to prepare various alternatives far self-sustained growth in coastal fishing. 3) Especially fisheries finance should play more active role. 4) Self-sustainable growth means a fishery with full compatability. For full compatability it is necessary to give financial supports far making fishing ground and equipping anti-pollution system and labour saving apparatus etc. 5) Also to raise the ratio of self-support in fisheries products it is necessary to give financial support to traditional financial system. 6) Moreover it is necessary to guide utilization of finance supplied. For this the committee that is consists of professional people in that field is strongly asked. This committee should be entitled to decide and coordinate the selection of projects, allocation of finance, method of utilization and evaluation of projects etc.

• 한국환경과학회지
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• 제30권10호
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• pp.811-820
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• 2021

The population variation of Spanish mackerel (Scomberomorus niphonius) according to its major prey abundance was analyzed using monthly catches of coastal set net fisheries in the southern waters off Gyeongsangnam-do and eastern waters off Gyeongsangbuk-do of Korea from 2006 to 2019. The abundance of Spanish mackerel and its prey species fluctuated almost simultaneously with time lags of +2 to -2 months between the set net fisheries in the southern and eastern waters. The generalized additive model revealed that the abundance of Spanish mackerel was influenced by its prey species such as hairtail and anchovy in southern waters, and common mackerel and horse mackerel in eastern waters. The model deviance explained 49% and 42% of Spanish mackerel abundance in southern and eastern waters respectively. These results suggest that the abundance of Spanish mackerel is affected by seasonal migratory prey fish species in the coastal areas and can be linked to their northerly migration.

• 생명과학회지
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• 제26권11호
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• pp.1237-1244
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• 2016

한류성 어종인 명태는 우리나라 동해를 비롯한 일본, 러시아 북부의 오호츠크해, 베링해, 알래스카 등지에 서식하는 중요한 수산자원으로, 우리나라에서는 그 어획량이 매년 감소하고 있어, 그 자원량의 회복과 보존 및 관리가 필요한 대표적 어종이다. 그러나, 이러한 중요성에도 불구하고 국내에서 명태의 유전학적 집단 분석에 관한 연구는 많이 수행되지 않은 실정이다. 본 연구에서는 우리나라 동해, 러시아, 미국 명태 집단 및 일본 명태 집단과의 유전적 다양성과 유연관계를 분석하여 명태자원의 보존과 관리를 위한 과학적 자료를 제공하기 위해 유전적 다양성 및 계군 분석에 널리 사용되고 있는 microsatellite marker (msDNA) 8개를 사용하여 명태 집단의 유전자형을 분석하였다. 우리나라 동해, 러시아, 미국 및 일본 집단에서 채집된 총 186개체를 분석한 결과, 대립유전자수는 최소 7.13개에서 최대 10.63개로 나타났고, 평균 대립유전자의 수는 9.05개로 나타났다. 기대치와 관찰치 이형 접합율은 각각 0.698과 0.732로 조사되어, 현재 확보된 명태 집단의 유전적 다양성은 비교적 잘 유지되고 있는 것으로 나타났다. 유전학적 유연관계 분석을 위한 유전적 거리, Pairwise FST값, UPGMA와 주성분분석, AMOVA test 분석 결과, 우리나라 동해, 러시아, 미국의 명태 집단 간 유전적 차이는 거의 없었으나 일본 명태 집단과는 낮은 수치이지만 유의한 유전적 차이가 있음을 확인하였다(p<0.05). 본 연구에서 확인된 유전학적 분석을 통한 명태집단의 유전적 특성 및 주변국 집단과의 유연관계 분석결과는 우리나라 동해의 중요한 수산유전자원으로서의 명태에 대한 중요한 과학적인 근거자료가 될 것이며, 앞으로 명태 자원의 보존, 평가 및 이용에 활용 가능한 정보를 제공할 것이다.

• 한국수산과학회지
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• 제39권4호
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• pp.344-348
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• 2006

The ecological characteristics and stock biomass of the Shiba shrimp, Metapenaeus joyneri, in Korean waters were determined, using fishery data from the Ministry of Maritime Affairs and Fisheries (MOMAF) and available length frequency data. The instantaneous coefficient of total mortality (Z) of M. joyneri was estimated to be 4.191year, and the annual survival rate (S) was 0.015. The estimated instantaneous coefficient of fishing mortality (F) for recent years was calculated to be 1.94/year. The age at first capture of M. joyneri was 0.71 years. Based on these parameters, the annual biomass of the M. joyneri stock was estimated using a biomass-based cohort analysis and data on the annual catch in weight at age for 1993-2004 in Korean waters. During the study period, the biomass of the shrimp peaked in 1994 at about 9,082 metric tons. Subsequently, it decreased to 500 metric tons in 1998.

• Animal cells and systems
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• 제16권4호
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• pp.313-320
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• 2012

Genetic variation was surveyed at four microsatellite loci and 1416 base pairs (bp) of the mitochondrial DNA (mtDNA) cytochrome c oxidase I gene (COI) to clarify the genetic structure of the small yellow croaker, Larimichthys polyactis, in the Yellow and East China Seas, especially regarding four provisional populations, (one Korean and three Chinese populations). Based on microsatellite DNA variations, the estimated expected heterozygosity ($H_E$) in each population ranged from 0.776 to 0.947. The microsatellite pairwise $F_{ST}$ estimates showed no significant genetic differentiation between the populations. MtDNA variations also indicated no genetic structure in L. polyactis, but very high variability. The absence of genetic differentiation among and within populations of L. polyactis may either result from the random migration of the adult or the passive dispersal of the eggs and larvae.

• Fisheries and Aquatic Sciences
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• 제12권2호
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• pp.138-151
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• 2009

We quantitatively investigated compositions of fish and invertebrate bycatch in Korean shrimp fisheries. We sampled shrimp trawl bycatch from 48 commercial trawls over 1 year. These samples contained 108 taxa from 50 families, with 60 fish taxa contributing 51.2% of the total biomass and 48 invertebrate taxa 48.8%. However, 86.32% of the total individual organism density comprised invertebrates, while individual fishes made up the remainder. Within the bycatch, two fish species varied in population size structure by season, suggesting recruitment is seasonal in these taxa. Overall general catch characteristics (total bycatch biomass and organism density) varied significantly by season and tide, and a significant interaction effect was observed (season$\times$tide) on total density, but not on total biomass. The data collected will be used in designing a program of long-term bycatch monitoring.

• 한국해양바이오학회지
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• 제3권1호
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• pp.38-41
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• 2008

Fish is a major source of protein for the Senegalese population. Fishing plays a dominant role in the Government's policy towards generating employment. It currently generates about 100,000 direct jobs (fishermen) for nationals, of which more than 90% are in small-scale fishing. The fishing industry also contributes to Government revenue through different agreements. In addition to associated dues, fishing agreements imply a series of economic, trade and technical counterparts. Under the latest fishing agreement concluded by Senegal and the European Union (1997-2001), direct financial compensation amounts to about CFAF 32 billion. Despite its economic and social importance, the sector has to face serious disequilibria both in resource exploitation and market supply: the coastal demersal (deep lying fish) stocks with high market value (mostly exported) are fully and even over-exploited, with a serious risk of local market supply shortages looming ahead as the fishing effort shifts from locally consumed species to export-oriented ones.