• The Korean Journal of Ecology
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• v.25 no.1
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• pp.59-62
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• 2002

Dokdo, which is located in the middle of the East Sea, is a small island tilth a total area of 0.186 $\textrm{km}^2$. However, this small island, with its mild oceanic climate, has rich bio-resources and picturesque natural surroundings. Dokdo in the crystaline waters and In the central area of the deep sea is a treasury of algaes (sea oak, sea mustard, gulf weed, laver, agar-agar, etc.), molluscs (squid, ear shell, conch, etc.) and fishes (Alaska pollack, anchovy, saucy, herring, etc.). On the other hand, there are a lot of grasses and various kinds of grasses on the land of Dokdo. And a lot of back-tailed gulls (about 20,000 Individuals) live on this island. There have been disputes on the sovereignty over Dokdo between Korea and Japan. Japan has claimed sovereignty over Dokdo since Japan incorporated the island into Japanese territory in 1905 when it occupied the Korean Peninsula by force. Korea governed Dokdo not only before 1905 but also after its liberation in 1945. The Korean government, while heavily financing building facilities like pleas and quays, is endeavoring to preserve the natural surroundings of this island.

• Journal of Species Research
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• v.8 no.4
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• pp.373-379
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• 2019

Two parasitic copepods, poecilostomatoid Colobomatus mylionus Fukui, 1965 and siphonostomatoid Clavellisa chinensis ($Y{\ddot{u}}$, 1933), were reported for the first time from Korea and redescribed based on the females collected from the marine fish of Korean waters. The C. mylionus was collected from the blackhead seabream, Acanthopagrus schelegelii(Bleeker). Colobomatus mylionus had been frequently reorded from marine teleost fishes from of Eden, Newcastle, Brisbane, Yelloon, and Point Sampson. The second record was C. chinensis redescribed based on the speciemens collected from the gills of a Japanese grenadier anchovy, Coilia nasus Temminck and Schlegel. Some differences were observed between the orginal description of known specimens examined in this study, these differences do not warrant a change in the taxonomic staus of the two species. The attachment site of all two copepods reported from Korea were the cephalic sensory canals and gills.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.404-418
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• 2013

In this study, we conducted field surveys to investigate and analyze species and length composition of catch from gape net with wings being set in two areas - Masari, Supomri - located in southern part of Jin-do for understanding fishing characteristics of gape net with wings fishery from March to September of 2011. And with those results, we attempted to propose fishery management strategy to harvest fisheries resources continuously. Catch obtained from field surveys comprised total 78 species, which accounted for 53 species of fish, 20 species of crustacean, 4 species of cephalopod and one of polychaete. As to species composition in weight, it showed that there was 88.5% for pisces, 9.0% for cephalopoda and 2.5% for crustacea. As to catch specifics by area, there was 36 species (596,891 individual, 456,551g) of pisces, 17 species (35,815 individual, 12,909g) of crustacea and 3 species (2,876 individual, 3,004g) of cephalopoda in Masari area. In Supumri area, there was 41 species (396,898 individual, 281,457g) of pisces, 15 species (16,113 individual, 7,772g) of crustacea and 4 species (6,792 individual, 72,329g) of cephalopoda and one polychaeta (36 individual, 11g). Catch of anchovy by month recorded on high level on June, July, September in both areas. When considering size composition by month, it was found that new populations recruit to these fishing grounds on June and September. Most of bycatch species including hairtail (Trichiurus lepturus), dotted gizzard shad (Konosirus punctatus), conger eel (Leptocephalous), Pacific sandlance (Ammodytes personatus), horse mackerel (Trachurus japonicus) were juvenile, and grass puffer (Takifugu niphobles), Kammal thryssa (Thryssa kammalensis), Japanese sardinella (Sardinella zunasi) were also small in size. As a result, it is considered that gape net with wings fishery which is likely to catch juvenile needs to be set fishing prohibit period for conserving above stocks during the period excluding main fishing periods of anchovy or fisheries management such as expanding mesh size for preventing juvenile catch.

• The Journal of Fisheries Business Administration
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• v.35 no.1
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• pp.133-168
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• 2004

The purpose of this study is to examine the state and characteristic of seafood marketing in Korean West Coast during the colonial period ruled by Japan. To accomplish the purpose, we tried to set the fisheries statistical database by reviewing of $\boxDr$Statistical Annual Report of Chosun Chongdokbu$\boxUl$ and $\boxDr$Official Report of Chosun Chongdokbu$\boxUl$. A trend analysis was carried out with the data. Also, by reviewing of articles related to the state of seafood marketing via $\boxDr$Daehan Maeil Newspaper$\boxUl$, $\boxDr$Maeil Newspaper$\boxUl$ issued at the period, we could find out some meaningful findings which backed up the statistics in realistic facts. For numbers of businessman in seafood marketing, it was clear that the number of Japanese businessmen increased more quickly than that of Korean compared with other sphere of fisheries. That means Japanese grasped Korean seafood market in a short time. In price of seafood in terms of cities, Kunsan was comparatively higher than Incheon and Mokpo. In price of seafood in terms of species, ‘Snapper’ was mostexpensive, and ‘Mackerel Pike’, ‘Anchovy’, ‘Mullet’, ‘Eel’, ‘Flatfish’ followed in that order. In price of a species in terms of ‘Yellow Croaker’, which was famous in West Sea, ‘Croaker with salt’ was more expensive than dried and fresh one. For the transition trend of number of fish market, we could ascertain that the number of market increased until 1919, however, it decreased slowly from 1932. That means Japanese government went to war against China from 1931. Of the West Coast, the number of fish market in Chungnam province was most high, but that of Chonbuk outrun from 1940. At that time, the number of fish market in West Coast reached to 34% out of that of whole country. In 1919, the proportion of seafood sales amount of West Coast neighboring provinces, such as Kyunggido, Chungnam, and Chonbuk, was 23% of whole country which rose to 28% in 1929, and 29% in 1939. Therefore, we could assure that seafood marketing was very active at that time in the region. When we consider the trend of seafood export at the main ports of West Coast, in 1910's, the export through Mokpo and Inchon port was very live but that of Kunsan was very tiny. However, in 1920's, the export amount of Inchon port did not much change, but that of Mokpo decreased, whereas, that of Kunsan increased. In the early and middle of 1910' s which was around beginning of Japanese ruling period, we realized that the imperialist Japan was very eager in political efforts to enhance the mind of seafood's quality improvement through the opening of several fisheries competitive shows and fairs.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.217-222
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• 2013

Sea temperature in the South Sea of Korea has been increased over the last decades. Seabirds are sensitive to changes in food availability in marine environment. In this study, we investigate the diet of Black-tailed gulls (Larus crassirostris) during the breeding season to identify changes of marine environment and biological response such as breeding performance in the South Sea of Korea. A total of 22 fish species or family (n = 128) from regurgitates by chicks were collected on Hongdo Island in 2002 and 2012. The most important prey item was Japanese anchovies (Engraulis japonicas). Proportion of Anchovy in diet increased in 2012 (70.5%) compared to 10 years ago (27.5%). Some species were newly found in 2012: Spotted chub mackerel (Scomber australasicus), Pacific sand lace (Ammodytes personatus), White ventral goby (Acanthogobius lactipes), Silver-strip round herring, Multicolorfin rainbowfish (Halichoeres poecilopterus), Silverside (Hypoatherina tsurugae), Surfperch (Neoditrema ransonneti) and Spotnape ponyfish (Leiognathus muchalis), but not in 2002. Especially, sub-tropic fish such as Kammal thryssa (Thryssa kammalensis), and Rosefish (Helicolenus hilgendorfi) were frequently observed in the diet of 2012. These results might reflect the increase of sea temperature in the South Sea of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.92-97
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• 2017

The feeding habits of larval Engraulis japonicas (3.2-11.0 mm SL) were examined based on 414 individuals, collected in October 2010, and from June to September 2011, in the coastal waters of Eastern Jinhae Bay, Korea. E. japonicus, fed mainly on copepods 62.6% IRI and tintinnid were the second-largest dietary component. E. japonicus diet also included small quantities of rotifers, eggs and diatoms. The results of analysis of ontogenetic changes showed that E. japonicus of small size classes (${\leq}4mm$) fed primarily on tintinnids. The dietary percentage of copepods decreased, as fish size increased, and monogeneans became increasingly important as size class increased above 4-6 mm. The highest rate of daily feeding E. japonicusi took place during the day.

• Journal of Life Science
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• v.16 no.5
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• pp.812-827
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• 2006

To investigate the population structure and geographic distance among anchovies (Engraulis japonicus) in Korea, we compared and analyzed the mitochondrial DNA control region sequences (227 bp) of anchovies from 12 localities in inshore and offshore waters. The sequence analysis of 84 individuals showed 29 haplotypes, ranging in sequence divergence by pairwise comparisons from 0.3% to 3.5% (1 bp-12 bp). E9 haplotype of anchovies were found largely in inshore waters and also in offshore waters, which was regarded as the major source in Korean waters (58.3%). However, E26, E27, E28, and E29 haplotypes were found in westsouthern (locality 10, four among 7). Phylogenetic analysis using PHYLIP was divided into two clades (clade A and B). Most of the haplotypes, excluding E26, E27, E28, and E29, were strongly supported by bootstrap analysis (>75%), whereas the relationship between clade A and B was weakly supported by bootstrap analysis (51%). High levels of genetic diversity were found; haplotype diversity (H)=0.75-1.00, and nucleotide diversity $({\pi})=0.015-0.0244$. Analysis of $F_{ST}$ between populations in inshore waters ranged in 0.01-0.05, whereas those of offshore waters ranged in 0.01-0.58. A high gene flow occurred in inshore (Nm=22.61-34.22) and offshore (Nm=11.57-45.67) populations. The distribution of mitochondrial DNA haplotypes between westsouthern and other populations was suggestive of significantly different differentiation ($F_{ST}$=0.20-0.59, p<0.05; d=0.52, p=0.00; ${\phi}=0.02-0.41$, p＜0.05). These results suggested that the overall anchovy population in the Korean peninsula caused considerable migration due to the mitochondrial gene flow between inshore and offshore populations to form a genetically homogenous and panmictic structure, although a heterogeneous population was found in this study.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.452-468
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• 2012

Marine organisms were collected by the stow nets and the stow net on boat fisheries from April 2010 to November 2011 in the Han River Estuary and categorized as 126 species, 61 families, and 5 taxa. The species were consisted with 34 in Crustacea, 5 in Cephalopoda, 79 in Pisces, unidentified jellyfishes in Cnidaria, and Finless porpoise in Mammals. The major species were composed of fish and crustaceans in the Han River Estuary. The dominant species in Crustacea were Chinese ditch prawn (Palaemon gravieri), blue crab (Portunus trituberculatus), Ridgetail prawn (Exopalaemon carinicauda), and mantis crab (Oratosquilla oratoria), and those in Pisces were Korean anchovy (Coilia nasus), and Japanese grenadier anchovy (Coilia mystus). The length structures of the six dominant species have more than one mode in the Han River Estuary. It reflects that the species inhibit during a part of and/or whole lifetime in the Han River Estuary where they utilize as spawning and/or nursery grounds. Freshwater fishes were collected from station D where is the closest location to the Han River stream, and their appearances were well matched with the large amount of freshwater discharge due to flood periods. Principal components analysis (PCA) was carried out with species compositions and showed temporal and spatial differences by the variations of species.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.134-142
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• 2017

Nando Island is reported as one of the biggest breeding colonies of seabirds in South Korea, and is protected as a Natural Monument. This study was conducted between July to November 2015, to investigate the breeding population of Black-tailed gulls and their habitat on Nando Island. We estimated the breeding population of Black-tailed gulls (Larus crassirostris) using nest density. The mean nest density of Black-tailed gulls was $0.51\;per\;1m^2$ ($0.51m^{-2}$), and the breeding population was approximately 26,760 individuals. The dominant vegetation was Echinochloa crusgalli and Agropyron tsukushiense var. transiens, which served as shelter and nest sites to Black-tailed gulls. The diet of Black-tailed gulls was mainly the fish, Japanese Anchovy Engraulis japonicas (48%). Other species which were found to breed on Nando Island were Streaked Sheawater (Calonectris leucomelas), Temminck's Cormorant (Phalacrocorax capillatus), and Swinhoe's storm petrels(Oceanodroma monorhis).

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.193-198
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• 2012

Long term changes in winter time(JFM) sea surface temperature(SST) and marine ecosystem of different Korean waters during last five to six decades were illustrated. Fishing intensity with climate-ocean variability(e.g. SST) have been increasing since 1970s in all of the Korean marine waters. Winter SST around Korean waters went to colder regime in early 1980s and after the late 1980s increased gradually. After 1988/89 CRS all of the waterbody started warmer regime and well coincided with the CRS phenomena. Large predatory, small pelagic and crustacean and mollusks abundance were well coincided by the warmer SST regime after 1988/89 CRS and changed the fishery from demersal fishery to pelagic fishery. Ecosystem parameter of Mean Trophic Level(MTL) showed continuous decreasing trend since mid of 1970s which was mostly affected by the increasing of lower trophic level species. Fishing in balance(FIB) index showed increasing pattern since early 1970s to the late of 1970s and from early 1980s it was almost stable until now. Finally wasp-waist population of anchovy and Japanese sardine have a greater impact to the whole MTL since early 1970s.