• Animal Systematics, Evolution and Diversity
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• no.nspc2
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• pp.199-221
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• 1988

Bopyrid isopods collected from 35 localities in Korea were examined. Twelve species in 12 genera were identified and classified onto 7 subfamilies, of which following 8 species are new to Korea : Metaboyrus ovalis Shiino, Bopyrissa pyriforma (shiino), Ione cornuta Spence Bate, Parapenaeonella distincta Shiino, Bopyriodes Hippolytes (Kroyer), Pseudostegias dulicilacuum Markham, Athelges takanoshimensis Ishii and Eophrixus shojii Shiino. Athelges japonicus Shiino is found out to be a junior synonym of a.takanoshimensis Ishii. Eight unrecorded scpecies in Korea are descried with figures. Other two species , Apocepon pulcher Nierstrasz et Brender Brandis and Argeia pugettensis Dana. Are provided with figures.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.142-148
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• 2015

The feeding habits of the Pacific cod Gadus macrocephalus were studied using 620 specimens collected by bottom trawl and pound net in the Southeast sea of Korea, from February 2012 to June 2013. Of 620 specimens, 192 contained food and 428 were empty. The total length (TL) of individuals used in this study ranged from 20.4 to 95.2 cm. Pacific cod mainly consumed Pisces, Macrura, and Cephalopoda. Its diet also included small quantities of Anomura, Brachyura, Mysidacea, Isopoda and Amphipoda. The proportion of Pisces in prey items increased with increasing Pacific cod length, but seasonal difference was not observed. The proportion of Macrura and Cephalopoda decreased with growth, and seasonal differences were apparent. Macrura were taken there mainly from autumn to winter, whereas Cephalopoda were consumed from spring to summer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.10-17
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• 1999

Feeding Habits of Acanthogobius flavimanus collected from the eelgrass bed in Kwangyang Bay from January to December 1994 were studied. A. flavimanus was a carnivore which consumed mainly polychaetes, crabs, shrimps, gammarid amphipods and fishes. Its diets included small quantities of ophiuroids, gastropods, bivalves, caprellid amphipods, isopods and tanaids. It showed ontogenetic changes in feeding habits. Small individuals fed mainly on polychaetes and amphipods. While the consumption of polychaetes and amphipods decreased with increasing fish sin, the consumption of shrimps, crabs and fishes increased. A. flavimanus fed diverse prey organisms in adult stage. The relative proportion of the major prey items changed with season. Although the consumption of polychaetes, shrimps and gammarid amphipods was relatively high in spring and autumn, A. flavimanus fed various prey organisms in nearly equal proportions in the other seasons.

• Journal of Environmental Impact Assessment
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• v.19 no.6
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• pp.539-546
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• 2010

In nature, the overall effect of heavy metals on the biota can be influenced by a number of environmental factors like soil characteristics and air pollution by elevated $CO_2$. Pillbugs(Isopoda, Armadillium vulgare) take up heavy metals with their food and store them mainly in the vesicles of hepatopancreas. They accumulate certain metals, occuring in relatively large numbers, are easily collected and identified. Therefore, it has been suggested that total body concentration of metals in pillbugs could be positively correlated to the levels of environmental exposure and that pillbugs could be used as biological indicators of metal pollution and global change by $CO_2$. The aim of the study is to determine effects of heavy metal concentrations in soil and elevated $CO_2$ on pillbugs'body accumulation of heavy metal and growth rate. In this study, pillbugs were collected at five sites (N=287) May 2006. Cu and Zn concentrations in pillbugs were higher than in soils (1.39-41.70 times) than in control. The high bioconcentration of lead in Sangam may be partly associated with reclaimed land uses. Pillbugs in low $CO_2$ and Pb condition showed higher growth rate than in elevated $CO_2$ and Pb condition.

• Journal of fish pathology
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• v.36 no.2
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• pp.403-408
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• 2023

Mullet is an important marine aquaculture fish species in Korea, with a total of 7,237 tons produced as of 2022, making it the 5th most produced marine aquaculture fish species. In this study, ectoparasites presumed to be isopods were discovered in the fins of farmed flathead grey mullet (average weight 550 g), and the characteristics of the parasites were confirmed. The length of the parasite was 5 to 18 mm, and 3 to 7 parasites were infected per fish. To analyze the characteristics of the parasites, molecular biological identification and phylogenetic analysis were performed using the cytochrome c oxidase subunit I (COI) gene, and it was confirmed to be most closely related to Nerocila japonica in the Cymothoidae family. To confirm the parasite control effect, a direct exposure drug sensitivity test was conducted on five types of aquatic drugs and fresh water, trichlorfon was confirmed to be effective.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.47-62
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• 1969

A goby, Synechogobius hasta (Temminck et Schlegel) was studied to investigate the food consumed and the biological change of the food organisms, and the fish were sampled from the closed tributary and the lower Part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The fish were sampled from four stations (Fig. 1), the total number of fish being 1,295 and they were grouped and analysed monthly. The content of the alimentary canal was analysed in three categories according to modified Nilsson's method (Dahl 1962) with a slight alteration: 1) The number of each item of stomach contents was counted and the percentage of each item in proportion to the total number of food organisms is indicated by the letter 'N' representing numerical percentage in Table 2. 2) The percentage of fish which contained any items of food organisms in proportion to the total number of fish caught in a given season is indicated by the letter 'O' representing frequency of occurrence. 3) Dominant groups of food items were selected and the percentage of the number of each dominant item in proportion to the number of the food organisms belonging to the dominant groups is indicated by the letter 'D' representing dominance. All food organisms were classified in 50 food item categories and then they were grouped in 13 main groups (Fig. 2-1), and they were further divided into 1) obligatory bottom animals, 2) organic drifts and 3) actively swimming forms; according to the conditions of the animal communities within the habitat. Since the majority of its food was composed of the obligatory bottom animals ($94.6\%$), the fish appeard to be a typical bottom feeder. And the dominant food organisms of the fish is generally determined by the local composition of the benthic fauna within the fish habitat. And their seasonal rhythm occurs among the food organisms in the stomach by the biological interaction. Locality variation in the population of the same food organism occurs due to the difference of food organisms in the habitat of the fish at Seonam and Garak, and at Seongsan and Hadan the condition of the niche for the fish in the both regions seems to be the same since the composition and the seasonal variation of the organisms were the same. The results may be summarized as follows: 1) The goby mainly feed on the animals of bottom fauna, and the food organisms are deter-mined by the food compositions within the habitat. 2) Seasonal variation of the stomach content shows the seasonal rhythm due to the biological variation of the population and their interaction. 3) The goby shows no preference on specific food, and the food is composed of a variety of animals. 4) Major food items of the goby are Polychaeta, Palaemon modestus, Isopoda, Gammaridea, Insecta (nymphs and larvae), Ilyoplax deschampsi, and Paratye compressa. 5) Logitudinal succession oil the population of the food organisms is apparently recognized within the community of Seongsan, Garak and Seonam. 6) The goby begins to descend toward the estuary and sea around April when the water temperature reaches $20^{\circ}C$, and they begin to return to river waters in September.

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.208-219
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• 2020

Forest thinning brought the large variation to forest ecosystem including environment and animal. Our study was result of long-term monitoring for ground-dwelling arthropod communities after thinning in forest ecosystem. In this study, we conducted field study on plantation forest in Chuncheon, Korea in 2018, and compared with previous study data (2006 and 2008). We found that the effect of thinning was still existent 10 years later from thinning with difference of habitat environment(depth of ground organic matter, coverage rate of ground vegetation and canopy). And ground-dwelling arthropod communities showed changes of abundance and taxa at the study area and thinning conditions. Ground-dwelling arthropod communities in 2018 were dominant in the order of Diptera, Hymenoptera, Coleoptera (Insecta), Araneae (Arachnida) and Collembola (Collembola). Among the conditions of thinning, Araneae (Arachnida), Coleoptera and Hymenoptera (Insecta) showed amount of abundance in heavy thinning. And Collembola (Collembola) and Diptera (Insecta) were most common in area of light thinning. In 2018 ground-dwelling arthropod communities, abundance of Diptera and Coleoptera (Insecta) and Isopoda (Crustacea) were decreased although Hemiptera and Orthoptera (Insecta) were increased than 2008 arthropod communities. Arthropod communities in 2018 were more similar with those in 2008 (after thinning) than with those in 2006 (before thinning).