• Korean Journal of Ichthyology
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• v.32 no.2
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• pp.91-96
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• 2020

Seasonal fluctuation in abundance and species composition of fish in coastal waters off Nang island were investigated using seasonal samples collected by long-bag stow net in 2017. A total 10,208 fish were sampled and classified into 37 species, 26 families, and 9 orders. The dominant species were Engraulis japonicus (4,886 individuals, 47.9%), Pennahia argentata (842 individuals, 8.2%), and Ilisha elongata (369 individuals, 3.6%). The diversity index was the highest in May (H'=3.23) and the lowest in November (H'=1.24). The dominance index was the highest in November (D=78.7%) and the lowest in May (D=22.4%).

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.172-177
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• 2019

Seasonal fluctuation in abundance and species composition of fish in coastal waters off Dolsan island were investigated using seasonal samples collected by an otter trawl in 2012. A total of 4,848 fishes were sampled and classified into 52 species, 29 families, and 7 orders. The dominant species was Leiognathus nuchalis (2,786 individuals, 57.5%), Amblychaeturichthys hexanema (164 individuals, 3.4%), and Ilisha elongata (141 individuals, 2.9%). The highest number of individuals was found in summer (2,174 individuals), while the lowest number of individuals was found in winter (321 individuals). The diversity index was the highest in spring (H'=3.06) and the lowest in summer and fall (H'=1.77). Temperature was the principal factor to determine the collected number of individuals (r=0.94) and the number of species (r=0.83).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.217-232
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• 2019

It was turned out by shrimp beam trawl monthly survey from March, 2015 to February, 2016 that different species composition and abundance of the fish assemblages in Sacheon Bay and coastal waters off Namhae, Korea were compared. As a result of monthly measured sea temperature and salinity of Sacheon Bay and coastal waters off Namhae, sea temperature of both areas was changed seasonally; however, differences in sea temperature occurred during certain periods depending on the region. Salinity was generally low in Sacheon Bay affected by fresh water, and both areas was low in summer and high in winter. A total of 73 species representing 37 families were collected in Sacheon Bay. The dominant fish species in terms of numbers and biomass were Liparis tanakae, $23,077inds./km^2$, $332.1kg/km^2$. A total of 91 fish species representing 49 families were collected in coastal waters off Namhae. The dominant fish species in terms of numbers were Leiognathus nuchalis, $139,683inds./km^2$ and biomass were Chelidonichthys spinosus, $1,078.6kg/km^2$. Analysis of dendrogram of the clustering showed that Sacheon Bay and coastal waters off Namhae were distinctive featured (global R = 0.691, p = 0.017). And except of summer season (July-October), there was a distinctive feature seasonally (global R = 0.844, p = 0.001). The fish species that appeared in common in both areas, where fish species caught in Sacheon Bay, an important inner bay,were smaller than those caught in coastal waters off Namhae appeared. It presented that Sacheon Bay plays a more important role in spawning and nursery ground for fisheries resource than coastal waters off Namhae, Korea.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.24-31
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• 1998

This study was performed to investigate the difference in species of test fish on the determination of short-term bioconcentration factor in zebrafish(Brachydanio rerio), red sword tail(Xiphophorus hellieri) and goldfish(Carassius auratus). Experimental concentrations of carbamates were 0.05 and 0.10 ppm and chlorothalonil were 0.005 and 0.01 ppm for 3 and 5 days, respectively. This paper reports the measured BCF value on pesticides in various species of test fish, under steady state, and examined correlation between the BCF value and depuration rate constant or LC$_{50}$ or lipid content. Carbamates and chlorothalonil concentration in fish extract and BCF of carbamate and chlorothalonil were increased as incresing test concentration. Carbamates concentration in fish extract and BCF of carbamate were decreased as incresing test period, but chlorothalonil concentration in fish extract and BCF of chlorothalonil were increased as prolonging test period. Determined pesticide concentration in fish extract and BCF were highest in red sword tail, and followed by goldfish, and zebrafish. Determined depuration rate constant were highest in zebrafish, and followed by goldfish, and red sword tail. 96hr-LC$_{50}$ were highest in red sword tail, and followed by zebrafish, and goldfish. Lipid compositions were highest in red sword tail, and followed by goldfish, and zebrafish. Therefore, it is suggested that the difference of BCF between each pesticide due to those of lipid composition of fish and deputation rate constant, while LC$_{50}$ have no effect on BCF.

• Fisheries and Aquatic Sciences
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• v.24 no.1
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• pp.41-52
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• 2021

Data for fish species composition and the catch of fish species were obtained from the daily trading records for the period between April and December 2016 to 2018 at the set net fishing grounds in Yeosu Bay, Korea. The annual mean total catch was 195.8 tons, and the dominant species was the Spanish mackerel (Scomberomorus niphonius), which accounts for about 55 percent of the total catch. The catch increased in spring and autumn. Increase in spring is caused by not Spanish mackerel but other fish while the increase in autumn by Spanish mackerel. The distinct increase of the catch in summer, 2017 was due to the new recruitment of small-sized Spanish mackerel, which was probably to be from the fish population hatched in spring in the East China Sea. Our results showed a strong correlation between water temperature and catch fluctuation. The catch increases with the increase in water temperatures, and the periodic pattern of the water temperature and catch fluctuation is more consistent in the offshore waters, in which warm current flows, than in the coast waters.

• Journal of Korea Water Resources Association
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• v.42 no.6
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• pp.481-491
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• 2009

In this study, a comprehensive field monitoring was conducted to understand habitat conditions of fish species in the upper Geum river. Based on the monitoring data, riverine health conditions such as composition ratio of fish species, richness and dominance indexes, bio-diversity (dominance index, diversity, evenness and richness), and index of biological integrity were assessed, and optimal ecological flowrates were estimated using the habitat suitability indexes established for three fish species Coreoleuciscus splendidus, Zacco platypus and Pseudopungtungia nigra selected as icon species using the physical habitat simulation system (PHABSIM). The total number of species sampled was 20 species, and two sensitive species of C. splendidus (22.4%) and Z. platypus (22.0%) dominated the fish community. The estimated IBI values ranged from 34 to 42 with average being 38 out of 50, rendering the site ecologically fair to good health conditions. An optimal ecological flowrate of 9.0 cms was recommended for the representative fish species at the site.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.154-165
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• 2013

The species composition of the fish community was studied in four streams where fish kills have previously occurred in recent years; Worun Stream, Seo Stream, Jangnam Stream, and the Anyang Stream. The number of fish species varied from 22 to 86% compared to the number of fish species pre-fish kill. The recovery of fish populations in the streams seems to be determined by water quality and the presence of artificial structures in the streams. The Jangnam Stream, where alkaline pH caused a fish kill, showed a high recovery of fish species due to improvements in water quality. Anyang Stream had a low number of species, possibly because dissolved oxygen concentrations were intermittently low. Artificial structures in streams had a negative impact the recovery of fish species, particularly for benthic fish species. It appears that fish populations can recover rapidly when water quality improves or the movement of fish community is unimpeded. However, water quality and artificial structures in many streams in Korea still present adverse conditions for fish survival, deterring the recovery of fish populations. To conserve fish populations in streams, habitat all owing unimpeded movement for fish and controls on pollutant inputs are needed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.4
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• pp.306-314
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• 2018

Species composition and seasonal variation of aquatic organism at Baekryeong-do, Korea were investigated using pots in 2016. A total of 42 species, 90,050 individuals and 2,351,666 g of aquatic organism were collected. Among them, there were 12 species and 3,826 individuals of fish, 15 species and 51,237 individuals of crustaceans, 2 species and 54 individuals of cephalopods, 7 species and 33,981 individuals of gastropods, 2 species and 757 individuals of echinodea, 2 species and 187 individuals of shellfish, and 1 species and 8 individuals of holothuroidea. The dominant species in number of individuals were Pagurus ochotensis, Neptunea cuming, Cancer gibbosulus, and Buccinum yokomaruae, which accounted for 70.0% of the total number individuals collected. The dominant species in biomass were Neptunea cuming, Portunus trituberculatus, Cancer gibbosulus, and Pagurus ochotensis, which accounted for 65.3% of the total biomass collected.

• Korean Journal of Ichthyology
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• v.30 no.1
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• pp.55-64
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• 2018

Fish assemblages in a sandy shore and an eelgrass bed were compared based on monthly samples in the southern coastal water of Korea. Samples were collected by a beam trawl in the sandy shore and a surf net in the eelgrass from March to February 2012. The common fish species were Syngnathus schlegeli, Pseudoblennius cottoides, Pholis nebulosa, Favonigobius gymnauchen, Gymnogobius heptacanthus, Pseudopleuronectes yokohamae, Takifugu niphobles. Among them S. schlegeli, Urocampus nanus, P. cottoides, P. nebulosa, T. niphobles were high abundance in the eelgrass bed than in the sandy shore, whereas Acanthogobius flavimanus, Acentrogobius pflaumi, F. gymnauchen, G. heptacanthus, P. yokohamae were high in the sandy shore. Aulichthys japonicus, Hippocampus coronatus, Sebastes inermis, Lateolabrax japonicus, Siganus fuscescens were found in the eelgrass bed, and Thryssa hamiltoni, Mugil cephalus, Inimicus japonicus, Platycephalus indicus, Hexagrammos otakii, Furcina ishikawae, Liparis tanakae, Repomucenus curvicornis, and Eutaeniichthys gilli were observed in the sandy shore. Species composition and abundance varied seasonally in two habitats; The number of species and abundance was high in August and September, while biomass was the highest in April and September. Fish numbers as well as biomass were lowest in February. Number of individuals and biomass of fish in the eelgrass bed were significantly higher than those of in the sandy shore. Some fish preferred to live in the eelgrass were collected in the sandy shore, while fish preferred to live in the sandy shore were rarely collected in the eelgrass.

• Korean Journal of Ichthyology
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• v.2 no.2
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• pp.182-202
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• 1990

Gobiid fish were collected monthly in Cheonsu Bay by a beach seine from the shallow water and by an otter trawl from the deep water from September, 1984 to August, 1986. Seasonal variation in species composition and biology of the major species were examined with the data of length and age composition. Fourteen speices of gobies were identified. Gobiid fish were more abundant in the shallow water than in the deep water. In the shallow water, they constituted 66% and 39% of the fish collected in the mud flat and the sand beach, respectively. The suction discs of the gobies explains that they inhabit successfully in the surf zone where the wave action is strong. Of the major species, Chaenogobius mororanus predominated in the shallow mud flat. A large number of adults of this species were obtained in Spring and their juveniles were collected from Summer through Autumn. Favonigobius gymnauchen was abundant in the shallow water, especially in the sand beach. This fish seemed to spawn from May through June, about two months later than Chaenogobius mororanus. Acanthogobius hasta juveniles lived in the shallow water and moved into the deep water as the fish grew. Chaturichthys stigmatias was collected mainly in the deep zone.