• 한국수산과학회지
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• 제47권5호
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• pp.659-666
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• 2014

Our aim was to compare the community structure of fish in the coast of Wando Island between 2001 and 2013. Using a gape net with wings, we collected 61 taxa, wherein the most dominant species was Engraulis japonicus. The sea temperature in the middle layer of the survey station in 2001 (after June) was obviously higher than that in 2013, which was < $20^{\circ}C$. Except for Thryssa kammalensis in 2013, the log transformed individuals of seven dominant species, selected using a SIMPER (similarity-percentages procedure) analysis, decreased. Decreases in the individuals of Gobiidae spp., the warm-water species Trichiurus japonicus and Conger myriaster, and the migratory species Syngnathus schlegeli, Setipinna taty and Sardinella zunasi, which arrive in the southern coastal waters of Korea during summer-autumn, could be due to decreasing sea temperature in 2013. Thus, fish species diversity, estimated from rarefaction and k-dominance curves, declined in the coastal waters of Wando Island from 2001 to 2013, resulting in a significant difference in fish community structure.

• 한국수산과학회지
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• 제46권6호
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• pp.948-956
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• 2013

Seasonal variations in species composition and abundance of the fish assemblages in the coastal waters off Gadeok-do were determined using monthly sample collection by a small otter trawl in 2010-2011. Of a total of 65 fishes collected, the dominant species were Leiognathus nuchalis, Clupea pallasii, Thryssa kammalensis, Engraulis japonicus, Repomucenus valenciennei, Sillago japonica, Trachurus japonicus, Pennahia argentatus, Okamejei kenojei, Cynoglossus joyneri, Pholis fangi, Pleuronectes yokohamae, and Zoarces gillii. These 13 fishes accounted for 92.8% of the total number of individuals collected. The number of fish species, number of individuals, biomass, and species diversity indices fluctuated with the seasons. The peak number of fishes occurred in April, whereas the biomass of fishes was highest in August. The numbers and biomass of fishes were lower in February corresponding with the low temperatures, and diversity indices were lower in January than in any other month.

• 한국수산과학회지
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• 제46권6호
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• pp.917-922
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• 2013

Changes in fishing ground of the large pair trawler were investigated by year, month and species off Korean waters. We used catch data by sea-block lat.${\times}$long.:$30^{\prime}{\times}30$) of the National Fisheries Research and Development Institute (NFRDI) and monthly fishing production statistics of Korean statistic information service from 1990 to 2007. In the 1990s, the demersal fish like Larimichthys polyactis, Collichthys sp, Portunus trituberculatus and Muraenesox cinereus were the dominant species, and in the 2000s, they were changed from demersal fish into pelagic fish like Scomberomorus niphonius, Scomber japonicus, Engraulis japonicus and Todarodes pacificus. Species composition of catch showed temporal variation by cluster analysis deviding into 4 period, 1990-1994, 1995-2000, 2001-2003 and 2004-2007. Fishing ground in the 2000s was decreased up to 2/3 in the 1990s, while the density of catch in the fishing ground in 2000s was higher than the 1990s.

• 한국수산과학회지
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• 제50권6호
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• pp.829-836
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• 2017

This study investigated the species composition and abundance of floating fish eggs to determine the timing and location of spawning of fish inhabiting the coastal waters of Sagye, Jejudo Island. Eggs were collected with a Bongo net bimonthly from May 2009 to February 2010. Identifications were based on nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Eggs were determined to belong to 43 distinct taxa, 35 of which were identified to the species level. The assemblage spanned eight orders, 23 families, and 32 genera. The number of taxa collected varied from month to month, with 14 taxa (12 species) found in June 2009, 11 taxa (10 species) in October 2009, 10 taxa (nine species) each in August 2009 and February 2010, eight taxa (six species) in April 2009, and five taxa (four species) in December 2009. Five abundant species (Branchiostegus japonicus, Engraulis japonicus, Pseudolabrus sieboldi, Goniistius zonatus, and Halichoeres tenuispinis) together represented 52.8% of the total number of eggs collected during the study.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.435-441
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• 2011

The feeding habits of yellow goosefish Lophius litulon and John Dory Zeus faber were studied by analyzing the stomach contents of specimens collected in the South Sea of Korea. In total, 132 hauls were taken during six experimental trawl survey (Tamgu 1) cruises conducted on a seasonal basis (March 2005-October 2007). The main prey items of the two species were similar. Fishes and crustaceans were the most important prey, with neither species showing ontogenetic changes in preferred species. Specifically, Pennahia argentata was the preferred prey item of L. litulon, whereas Trichiurus lepturus and Engraulis japonicus were preferred by Z. faber. Larger Z. faber (>24 cm) preferred bigger prey such as T. lepturus and Larimichthys polyactis, while smaller Z. faber preferred E. japonicus and Acropoma japonicum.

• 수산해양기술연구
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• 제47권2호
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• pp.99-107
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• 2011

The relationships among long-term variation in catches of Spanish mackerel (Scomberomorus niphonius) and main food organism such as common mackerel (Scomber japonicus), anchovy (Engraulis japonicus), and oceanic condition in Korean waters were analyzed using 40 years of time-series data from 1971－2010. In the 1990s, oceanic conditions around the Korean peninsula shifted to a warmer regime with higher SST (sea surface temperature). The total catch of Spanish mackerel in Korean waters increased dramatically since the early 2000s, and main fishing ground form into South Sea in winter season from December to January. From the results of correlation analysis, we found a significant relationship between the Spanish mackerel catch and environmental factor such as SST, common mackerel and anchovy catch in Korean waters.

• 한국수산과학회지
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• 제47권6호
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• pp.983-996
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• 2014

Fish catches by a set net from January 2007 to November 2009 were analyzed to assess fish species composition and seasonal variations in the coast of Gijang, Korea. Over 389 kg fish representing 78 species, 45 families and 17 orders were collected during three years of the study. Dominant species were jack mackerel Trachurus japonicus, anchovy Engraulis japonicus and herring Clupea palasii, and these three species comprised 67.3% of the total number of individuals and 60.7% of the total biomass. Size distribution of the dominant species for jack mackerel, anchovy and herring ranged from 2.2 cm to 22.6 cm, from 2.5 cm to 14.8 cm, from 4.0 cm to 29.0 cm in fork length, respectively. Anchovy was the only species that occurred throughout all seasons in the Gijang coast. Generally, species richness was highest in spring (April to June) when sea temperature began to increase.

• 한국어류학회지
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• 제21권3호
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• pp.191-199
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• 2009

남해도 미조 정치망 어획물의 종 조성과 어획량 변동양상을 알아보기 위하여 2004년의 어기(3월 말부터 12월까지) 동안 매일 조사를 실시하였다. 조사기간 중 총 어종수 39종과 총 어획량 69,147.5 kg의 수산자원이 어획되었으며, 이중 어류가 33종 66,410.2 kg, 두족류가 5종 1,126.6 kg 그리고 갑각류가 1종, 1,610.7 kg을 차지하였다. 우점적으로 어획된 수산자원으로는 갈치, 까나리, 멸치, 삼치 등이며, 전체 어획량의 81.2%를 차지하였다. 이 외 정어리, 감성돔, 새우류, 살오징어 등이 소량 혼획되었으나, 전체 어획량에서 차지하는 비율은 낮았다. 우점어종 중에서 까나리는 봄철에 주로 어획되었고, 갈치와 삼치는 여름과 가을철에 그리고 멸치는 봄부터 가을철까지 계속 어획되었다. 미조 정치망의 어획량은 봄보다는 가을철 전후에 많이 어획되었는데, 이는 우점종인 갈치와 삼치의 어획량 증가에 따른 것이며, 이는 또한 $17^{\circ}C$ 이상의 어장 적수온과 관련이 있었다.

• 한국어류학회지
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• 제29권1호
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• pp.80-86
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• 2017

본 연구는 남해 중부 연안역에서 2016년 4~8월까지 자어군집구조의 월 변화를 조사하였다. 조사기간 동안 총 42종의 자어가 출현하였다. 우점종 중 멸치(E. japonicus)는 여름보다는 봄철에 우점하였고, 용서대(C. abbreviates)는 봄철에만 출현하였으며 수조기(N. albiflora)는 여름철에만 출현하였다. 자어 군집은 계절별로 4~5월 (봄)과 6~8월 (여름)의 그룹으로 유의하게 나눌 수 있었고, 여름철은 또다시 6~7월과 8월의 두개의 유의한 그룹으로 나눌 수 있었다. 2016년 8월 조사해역에서는 이상 고수온 현상이 발생하여 표면수온이 $28^{\circ}C$까지 상승하였고, 멸치와 수조기 자어의 출현량은 산란 적정수온을 넘은 수온으로 인해 급감하였다.

• 수산해양기술연구
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• 제51권4호
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• pp.553-560
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• 2015

The feeding habits of the Pacific bluefin tuna, Thunnus orientalis were examined based on the stomach contents of 330 specimens caught by offshore large purse seine fishery in the southern sea of Korea, 2011. The size of Pacific bluefin tuna used in this study ranged from 34.1 to 67.3 cm in fork length (FL). The percentage of empty stomachs was 41.8%. The main prey items were Pisces and Cephalopoda based on percentage IRI (index of relative importance). The main fish preys were Trachurus japonicus, Bregmaceros japonicus, Engraulis japonicus, and Cephalopoda were Todarodes pacificus, Loligo edulis, Watasenia scintillans. T. orientalis showed ontogenetic change in diet composition. Although Pisces dominated the diet of all length classes the portion of Cephalopoda was relatively higher in size between 40 and 50 cm other than length classes. In terms of seasonal variation in feeding habits, Pisces was the main prey group in all seasons, but Cephalopoda was also frequently consumed during spring and autumn based on %IRI.