• Korean Journal of Environment and Ecology
• /
• v.15 no.4
• /
• pp.401-407
• /
• 2002

Fishfauna were investigated in the Taebaeksan area streams. At the upper tributary of the Han River, 8 species of 4 families were collected and the dominant species was Rynchocypris oxycephalus. The two species, Rynchocypris kumgangensis and Silurus microdorsalis were Korean endemic species. Brachymystax lenok tsinlingensis, designated as a natural monument and vulnerable species was confirmed at the Jeongam-sa area streams At the upper streams of the Nakdong River, collected fishes were identified as 14 species of 7 families. The dominant Species was R. oxycephalus and subdominant Zacco temmincki. Korean endemic species were 8species(51.7%), Coreoleuciscus splendidus, Squalidus gracilis majimae, Microphysogobio yaluensis, Niwaella multifasciata, Silurus microdorsalis, Liobagrus mediadiposalis, Coreoperca herzi and Odontobutis platycephala. Brachymystax lenok tsinlingensis were confirmed at the Hyundong-Chon Stream and Baek-chon stream.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.12
• /
• pp.2265-2270
• /
• 2008

It was studied to the displacement and the amount of catch for migratory fishes with NOAA/AVHRR SST(Sea Surface Temperature) from 1988 to 2000 in the Korean Seas. The analyzed results from SST data showed generally the oceanic warming trend in the Korean Seas. On the increasement of SST, the distributed areas of migratory fishes which living in the warm waters were displaced gradually to the northward directions(high latitude) and then the amount of catch was increased during this studied periods against to migratory fishes which living in the cold waters.

• Korean Journal of Ecology and Environment
• /
• v.40 no.1
• /
• pp.103-109
• /
• 2007

To investigate the effects of artificial vegetation island (AVI) on fish distribution, we compared fish fauna from artificial vegetation island (AVI) area, which installed in 2000, natural vegetation area (NVA) and vegetation-free area (VFA) at Kyungan Stream area of Lake Paldang from Jul. to Nov., 2005. Results showed that 11 families 23 genera 24 fish species were distributed in the AVI and NVA. Squalidus japonicus coreanus, a small-size fish which generally lives at the downstream, dominated absolutely in the individual numbers. However, only 6 families 11 genera 12 species of fishes caught at the VFA, and dominant fishes were Hemibarbus labeo and Erythroculter erythropterus, a medium to large-size migratory fishes which live in mid-depth of water column. The dominance index was high at the AVI (0.778) and NVA (0.868), whereas the diversity index and evenness index were high at the VFA. Fish distribution at AVI was similar to that of the NVA in numbers of species, indicating that the AVI could playa role as spawning and inhabitation zone to a variety of fishes. We believe that AVI may be used for a restoration of the damaged and disturbed littoral ecosystem.

• Korean Journal of Ichthyology
• /
• v.9 no.2
• /
• pp.202-220
• /
• 1997

A total of 57 species of fish species was collected by a trawl from the eelgrass bed in Kwangyang Bay. The dominant species were Pholis nebulosa, Syngnathus schlegeli, Leiognathus nuchalis, Pseudoblennius cottoides, Sebastes inermis, Favonigobius gymnauchen, which accounted for 69.9% of the total numbers of fish collected. Fish collected in the study area were primarily small fish species or early juveniles of large fish species. Only about 10% of fishes which were collected in the eelgrass bed exceeded 15cm in standard length. Seasonal variations in both species composition and abundance were major characteristics in the study area. The peak abundance occurred in spring, while the number of species was the highest in fall. However, both the number of species and abundance of fishes showed the lowest values in winter. High species diversity indices were observed in fall. Temperature, eelgrass standing crop and abundance of food organisms influenced seasonal changes of the fish community in the study area. More abundant and more diverse fishes were collected during nighttime than daytime.

• 한국해양학회지
• /
• v.19 no.1
• /
• pp.44-55
• /
• 1984

Abundances of small fishes that utilized seagrass meadows of Redfish Bay, Texas, were analyzed quantitatively to determine monthly changes of this concentrated subtropical fish community during 1982-1983. an effective quantitative sampler, a 1-㎡ thrown cage, yielded a total of 10,223 fishes that comprised 40 species in 23 families, with average total densities about 15 fishes/㎡ in shoalgrass meadow and 6 fishes/㎡ in turtlegrass meadow. The darter goby, pinfish, code goby, and Gulf pipefish were the four most abundant species, and accounted for approximately 85% of the number of fish collected. However, the two different meadows had different relative abundances of fishes. The darter goby numerically dominated shallower shoalgrass meadow, while the pinfish and code goby were the commonest fishes in deeper turtlegrass meadow. Seasonal changes in both species composition and abundances of fish populations were major characteristics in these subtropical seagrass medows. Peak abundance of total fishes occurred during spring, with a secondary peak in fall. Lowest abundance of total fishes occurred in winter. Each abundant species showed its own seasonal abundance pattern, and had a peak abundance 1-3 months separated from other species, with some overlap of increased larval recruitment. Such distinct seasonal abundance patterns with different times of peak recruitment. Such distinct seasonal abundance patterns with different times of peak recruitment among fish species seem to permit use of the seagrass habitats with reduced, seasonal competition.

• Korean Journal of Environmental Biology
• /
• v.37 no.1
• /
• pp.8-18
• /
• 2019

The objectives of this study were to analyze the influence of chemical water quality on fish guilds, pollution tolerance and the multi-metric ecological health, based on the Fish Assessment Index (FAI) in the main stream of Mangyeong River between 2009-2016. The quality of water with specific conductivity, TP, and $NH_4-N$ got worse dramatically in the down region. During the study, a total of 50 species were collected and the most dominant species was Zacco platypus. Also known as tolerant species, accounted 22.9% of the total abundances, thus indicating a trophic degradation. The downstream region (S5) had the highest number of fish external abnormalities, indicating a degradation of ecological health, based on the fish assemblages. Pearson correlation analysis indicated that relative abundance of tolerant fish species and omnivore fish species had a significant positive correlation(r>0.30, p<0.05) with values of BOD, conductivity and $NH_4-N$. Whereas, the relative abundance of the sensitive species and insectivore species had a significant negative relations (r<-0.30, p<0.001) with the parameters. The mean obtained from the multi-metric fish model, based on the FAI of all sites was 47 (n=40). This indicated a "fair condition" in the ecological health, and the downstream regions (S3-S5) were judged as "bad condition", indicating an influence of the chemical degradation on the ecological health.

• Journal of Korea Water Resources Association
• /
• v.55 no.1
• /
• pp.99-109
• /
• 2022

This study was intended to suggest the applicability of stepped boulder fishway using the concept of traditional boulder weir, focusing on the problems of existing concrete pool-and-weir fishways installed in mountain streams. To achieve this purpose, a stepped boulder fishway was designed and constructed as a pilot project in consideration of ascending capacity of the selected target fishes. Under the given discharge conditions, the hydraulic characteristics of the fishway were investigated in the field, and the characteristics and ascending capacity of the fishes were compared and analyzed. The fishway had a short length and steep slope, but the mean drops between each baffle were the range of 0.15 to 0.29 m, and this range satisfied the limit condition of about 0.40 m, which was in the limit of the drop that target fishes can ascend. The mean velocities of each baffle and pool were 0.82 to 0.87 m/sec and 0.13 to 0.24 m/sec. This result satisfied the conditions of burst speed (10 to 30 times of body length) and mean velocity of the resting pool (7 to 25% of burst speed) for target fishes. Since the bottom surface of the pool formed of boulders had a gentle reverse slope and rotational flow did not occur, the efficiency of fishway can be increased, and it will also be possible to solve the maintenance problem by flushing bed materials.

• Korean Journal of Ichthyology
• /
• v.17 no.1
• /
• pp.64-72
• /
• 2005

The data for the present study were collected from the both-sides fyke net fishery in coastal Dolsan, Korea, from March 2003 to February 2004 A total of 2,402 individuals (432,42 kg) were collected and identified to 11 orders, 34 families, and 48 species. The most dominant order was the Perciformes, comprising 21 species in 15 families, followed by Scorpaeniformes, 8 species in 5 families, and Pleuronectiformes, 5 species in 3 families, These three orders constituted 67.9% of the total collected fish. The most dominant species, Acanthopagrus schlegeli, accounted for 279 individuals (20.26 kg), followed by Mugil cephalus with 187 individuals (99.61 kg), and Konosirus punctatus with 178 individuals (8.89 kg). The diversity index of the fish catches was 1.6823~2.9105 and was the highest in September 2003 and the lowest in December 2003. The evenness index was 0.6585~0.8872 it was the highest in August 2003 and the lowest in December 2003. The dominance index was 0.2000~0.6852, with the highest in December and the lowest in August 2003.

• Ecology and Resilient Infrastructure
• /
• v.9 no.1
• /
• pp.68-76
• /
• 2022

In this study, the Habitat Suitability Index (HSI) was calculated in the Miho stream of the Geum river system, and the environmental ecological flow by point was evaluated. Two points (St.3 and St.8) representing the up and downstream of Miho Stream were selected, in order to calculate the Habitat Suitability Index, the depth and velocity at point where each species is appeared were investigated. The Habitat Suitability Index (HSI) was calculated by the Washington Department of Fish and Wildlife (WDFW) method using the number collected by water depth and velocity section and the results of the flow rate survey. Two target species were selected in this study; dominant species and swimming species sensitive to flow. In the case of a single species of Zacco platypus, the water depth was 0.1 - 0.5 m and the velocity was 0.2 - 0.5 m/s. For species of swimming fish, the water depth was 0.2 - 0.5 m and the velocity was 0.2 - 0.5 m/s. The discharge-Weighted Useable Area (WUA) relationship curve and habitat suitability distribution were simulated at the Miho Stream points St.3 and St.8. At the upstream St.3 of Miho Stream, the optimal discharge was simulated as 4.0 m³/s for swimming fishes and 2.7 m³/s for Zacco platypus. At the downstream point of St.8, species of swimming fish were simulated as 8.8 m³/s and Zacco platypus was simulated as 7.6 m³/s. In both points, the optimal discharge of swimming fish was over estimated. This is a result that the Habitat Suitability Index for swimming fish requires a faster flow rate than the habitat conditions of the Zacco platypus. In the calculation of the minimum discharge, the discharge of Zacco platypus is smaller and is evaluated to provide more Weighted Useable Area. In the case of swimming fishes, narrow range of depth and velocity increases the required discharge and relatively decreases the Weighted Useable Area. Therefore, when calculating the Habitat Suitability Index for swimming fishes, it is more advantageous to calculate the index including the habitat of all fish species than to narrow the range.

• The Journal of Fisheries Business Administration
• /
• v.11 no.1_2
• /
• pp.89-114
• /
• 1980