• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.4
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• pp.357-362
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• 2006

The feeding habits of John Dory (Zeus faber) were studied by examining the stomach contents of 317 specimens collected from January 2004 to December 2005 in the coastal waters off Gori, Korea. The standard length (SL) of the specimens ranged from 12 to 42 cm. Z. faber is a piscivore and consumes mainly teleost fish such as Psenopsis anomala, Trichiurus lepturus and Conger myriaster. Its diet also includes shrimp and cephalopods. Smaller individuals (<25 cm SL) consume shrimp and small fish such as Glossanodon semifasciatus. The proportion of these prey items decreases with increasing fish size, and this decrease is paralleled by increased consumption of lager fish such as Psenopsis anomala and Trichiurus lepturus. The prey size increases with Z. faber size.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.851-859
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• 1997

This study was perfomed to investigate the contamination level of harmful heavy metals and the level of trace elements in 15 kinds of fish collected at the western coast in Korea from July to December in 1996. The levels of total lead, cadmium, mercury, iron, copper and zinc were determined and the results were summarized as follows: The minimum and maximum values(ppm) of fish, mean value bracketed, were ; Pb : 0.02~4.80(2.26), Cd: 0.001~0.54(0.04), Hg: 0.007~1.08(0.52), Fe: 7.76~66.39(25.70), Cu; 0.37~121.6(1.90), Zn:12.01~112.10(54.78). The results show that mean contents of Pb, Cd and Hg in 15 species fish were not yet dangerous levels enough to cause a health problem. But the contents of Pb and Hg tend to increase.

• Environmental Engineering Research
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• v.24 no.4
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• pp.638-645
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• 2019

This research was an evaluation of the fish fauna and the habitat for Brachymystax lenok tsinlingensis (B. lenok tsinlingensis) for 11 stations at the Bonghwa-gun sanctuary. The predominant species in this research area was Zacco koreanus. B. lenok tsinlingensis, which has been designated as an endangered freshwater fish in Korea, was found in the Bonghwa sanctuary zone, except at stations 5 and 6. The B. lenok individuals were shorter in length than 400 mm. In total, 13 endemic species were found, including Coreoleuciscus splendidus and Iksookimia longicorpus. Specimens of Koreocobitis naktongensis, a first grade endangered species, were also collected. The benthic macroinvertebrates consisted of four divisions, four classes, seven orders, 30 families, 60 species, and 10,344 individuals and were distributed among the orders Ephemeroptera (55.9%), Diptera (18.2%), Trichoptera (12.4%), Plecoptera (2.1%), and Odonata (0.3%).

• Journal of Korean Society on Water Environment
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• v.28 no.6
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• pp.943-953
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• 2012

Because of their unique properties, nano-sized metallic nanomaterials (NMs) have been used in extensive applications of biomedicine, electronics, optics, engineering, and personal care products. Accordingly, with the increasing release of NMs into the environment, numerous studies of nanoecotoxicity have been conducted. Fish embryo toxicity test (FET) has many benefits in evaluating toxicity of NMs as an alternative to a whole-body test in fish. In this study, we collected and analyzed the toxicity studies of metallic NMs on freshwater fish embryos. Most studies have demonstrated that metallic NMs are highly toxic during the early development of fish embryos. However, it should be noted that the results for the same NMs on the same test species show variation due to differences in the size or surface properties of the test NMs and exposure conditions. For the safe use of metallic NMs, we need to analyze their effects based on their properties, test species, environmental media, and diverse conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.510-520
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• 2010

This study investigated the community structure and seasonal variation of the fish assemblages on Jangbong tidal flat, Incheon, Korea. Fish were collected monthly using a small otter trawl from November 1999 to January 2001. Thirty-six fish species were recorded, with a mean density of 185 individuals and biomass of 2,594.3 gWWt. The most abundant species by number were Johnius grypotus (23.7%), Acanthogobius hasta (17.8%), and Cynoglossus joyneri (10.7%), while the dominant species by catch weight were Acanthogobius hasta (21.2%), Sebastes schlegeli (16.2%), J. grypotus (14.0%), and C. joyneri (10.8%). Cluster analysis and non-metric multi-dimensional scaling (nMDS) were applied to assess the seasonal fluctuation in the fish assemblages. Based on the result of the cluster analysis and nMDS ordination, the faunal group could be divided into cold- and warm-water specialist groups. The cold-water specialists included A. hasta, Acanthogobius luridus, Triaenopogon barbatus, Tridentiger trigonocephalus, and Liza haematocheila. The warm-water specialists were J. grypotus, C. joyneri, S. schlegeli, and Hexagrammos otakii. In conclusion, the community structure showed a distinct seasonal trend, which seemed to be related to the seasonal fluctuations in water temperature.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1379-1386
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• 2018

Conventional underwater cameras used in fish farms can only shoot limited areas and are vulnerable to underwater contamination. There is also a problem with contaminated farms as surplus residues are deposited as a result of feed supply to farms' nets. This paper proposes underwater drones for underwater monitoring of fish farms and cleaning nets. If underwater drones are used for management of fish farms, underwater imaging, monitoring and cleaning of fish farms' nets can be possible. By using this technology, data can be collected by detecting changes in the environment of a fish farm and responding to changes that occur within a fish farm based on the data. In addition, the establishment of an integrated control system will enable to build efficient and stable smart farms.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.2
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• pp.122-128
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• 2022

To present the spatial variation of fish assemblages in the Geum River in Korea, the concept of beta diversity (β-diversity) estimates based on the variance of the community data table was applied. Fish communities and environmental variables were collected from 13 sampling sites along the in mid-low reaches of the River. We calculated the β-diversity and local contribution to beta diversity (LCBD) values at each site depending on the two types of data, 'occurrence' with Jaccard and Sørensen dissimilarity coefficients, and 'abundance' with Hellinger distance. Multivariate and correlation analyses were also performed to determine the relationships between LCBD and other variables, such as community indices and physicochemical and hydrological factors. The β-diversity values of fish communities in the River were estimated as 0.218 and 0.145 for occurrence data table with Jaccard and Sørensen respectively, and 0.268 for abundance data. Similar patterns of LCBD along the sampling sites were detected in two dissimilarity measurements of occurrence table, and LCBD values with abundance data were slightly different. The LCBD values are strongly correlated with community indices, and also suitable for indicating the uniqueness of fish assemblages. However, further research is needed to determine the LCBD value as an indicator of environmental variability.

• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.238-248
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• 2010

We performed field investigations at six stations in Buk Stream of Goseong-gun, Gangwon-do, Korea, from May to September 2009 to understand the stream's fish fauna and community structure. In the survey, 31 species belonging to 20 families were collected. Dominant species by number was Zacoo koreanus (30.0%), and subdominant species were Pungitius kaibarae (9.4%) and Rhynchocypris steindachneri (9.3%). In biomass, the dominant species was Tribolodon hakonensis (35.5%), and subdominant species were Z. koreanus (22.5%) and Cobitis pacifica (7.5%). Eight Korean endemic fish species and two endangered species (P. kaibarae and Pungitius sinensis) were collected. In addition, four anadromous fish species (T. hakonensis, Oncorhynchus masou masou, O. keta, Gasterosteus aculeatus) and two amphidromus fish species (Plecoglossus altivelis altivelis and Gymnogobius urotaenia) were observed. Interestingly, we verified the existence of several fish species in Buk Stream where they have not lived before. Those species were previously reported to live only in rivers that run into the western and southern sea of Korea. Five of those species (Zacoo koreanus, Z. platypus, Silurus microdorsalis, Liobagrus andersoni and Coreoperca herzi) were reported in Buk Stream in the 1980s. The other species (Pungtungia herzi, Pseudorasbora parva, Squalidus multimaculatus, Misgurnus mizolepis, Koreocobitis rotundicaudata, Silurus asotus and Odontobutis interrupta) have been introduced since the 1990s.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.31-38
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• 2014

The fish community and upstream of glass eels (Anguilla japonica) in the Imjin River estuary Gyeonggi-do, Korea was investigated from 2008 to 2012. During the surveyed period 43 species belonging to 18 families were collected. Korean endemic species was Microphysogobio jeoni which showed a ration of 0.04% in collected species. Exotic fishes were Carassius cuvieri and Ctenophayngodon idellus, and comprised 0.06% of the total individual number. Among the fish species observed, 17 species of the freshwater fish (40.5%), 6 species of migration fish (14.2%), 8 species of the brackish water fish (19.1%) and 11 species of sea water fish (26.1%). In terms of composition ration, Anguilla japonica (glass eels, 49.8%), Coilia ectens (23.3%), Saurogobio dabryi (8.1%), Repomucenus olidus (3.3%), Lateolabrax maculata (2.9%) and Chelon haematocheilus (2.8%) were found to display high individual number. On the other hand, C. ectens (33.6%), C. haematocheilus (14.2%), Cyprinus carpio (10.5%), Mugil cephalus (9.1%) and S. dabryi (7.6%) were dominated of biomass. The dominant species of individual was A. japonica (glass eels), and subdomint species included C. ectens. The fish biomass catched of fisherman in the Imjin River (Paju-si) were 83.6~240.3 t by each year. The year 2011 and 2012 were decreased rapidly. Among these, M. cephalus (48.0~80.0%), C. carpio (6.7%), Carassius auratus (4.9%), Silurus asotus (3.9%), Takifugu obscurus (2.5%), Anguilla japonica (adult, 2.2%) and Pseudobagrus fulvidraco (2.1%) dominated of biomass. Body weight of glass eels at each year were 0.03~ 1.13 t, average 212.0 kg and 1,325,000 individual by 0.16 g each one individual.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.285-293
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• 2023

This study conducted to investigate the temporal and spatial variations in the fish community structure in the Seomjin River estuary (ES1~ES3) and Gwangyang Bay (ES4~ES8). Surveys were conducted at eight points between May and September from 2020 to 2021. A total of 5,111 fish were collected, representing 42 families, 68 genera, and 78 species. The dominant species collected during the survey period were Pennahia argentata, with 2,370 individuals and a relative abundance of 46.4%. Also, as a subdominant species, Nuchequula nuchalis, 1643 individuals were caught, accounting for 32.1% relative abundance. According to Bray-Curtis similarities, observations were divided into three groups based on the fish community composition, and they were further categorized into brackish water areas, coastal areas, inner areas, and outer areas. Group 1 mainly consisted of fish inhabiting freshwater and brackish water areas, while group 3 exclusively contained fish living in marine waters. ANOSIM (Analysis of Similarity) analysis revealed a significant difference (ANOSIM R=0.783, p=0.001) between Group 2 and Group 3, and the species contributing to these clusters were P. argentata and Muraenesox cinereus. The study demonstrated spatial changes in the fish community structure from the Seomjin River estuary to the outer coast. The findings highlight the importance of long-term monitoring of major species that exhibit spatial variations, serving as essential foundational data for the conservation and management of economically significant fish species.