• Korean Journal of Ichthyology
• /
• v.27 no.2
• /
• pp.116-132
• /
• 2015

Freshwater fish fauna and community structure were investigated at 44 stations in upper reach of the Nakdong river, Korea from March to October 2014. During the surveyed period 42 species and 4 types belonging to 34 genera and 14 families were collected. In this collection fishes of Cyprinidae were 17 species and 4 types, most numerous possessing 43.2% of all. There were 17 Korean endemic species including Kichulchoia multifasciata, 3 endangered species such as Koreocobitis naktongensis, Lethenteron reissneri and Brachymystax lenok tsinlingensis and 2 exotic species such as Lepomis macrochirus and Micropterus salmoides. Fish species transferred from other native rivers were 9 species including Hemibarbus mylodon, Coreoleuciscus slpendidus Han river type, Opsariichthys uncirostris amurensis, Iksookimia koreensis and Liobagrus andersoni. Dominant species based on the number of individuals was Rhynchocypris oxycephalus (21.44%) and sub-dominant species were Zacco koreanus NE type (18.55%). The community analysis revealed that the structure of fish community in upper reach of the Nakdong river was very stable and diverse in having diversity 1.101, evenness 0.670, dominance 0.400 and species richness 4.454. Fish community was divided into 5 groups based on similarity indices among surveyed stations such as uppermost, upper I, upper II, mid-upper, middle reach group.

• Korean Journal of Ichthyology
• /
• v.13 no.4
• /
• pp.261-266
• /
• 2001

The ichthyofauna and the structure of fish community were surveyed from June to August in 2000 at four stations of the Wondong marsh, Yangsan city in Kyungnam province. During the study period, 24 species belonging to eight families were collected. Cyprinid fish occupied 62.5% (15 species) and cobitid and centrarchid fish 8.3% (each 2 species). According to relative abundance in the whole marsh, Z. platypus (23.2%) was dominant species and S. gracilis majimae (14.2%) was subdominant species. M. salmoides (9.6%), C. auratus (8.3%), P. herzi (8.3%), M. yaluensis (6.5%), M. anguillicaudatus (4.0%), L. macrochirus (3.4%), P. parva (2.8%), R. ocellatus (2.5%), C. brevicauda (2.5%), C. sinensis (2.5%) and O. platycephala (2.2%) were common species and C. carpio, A. rhombeus, H. labeo, S. variegatus wakiyae, S. chankaensis tsuchigae, Z. temmincki, O. bidens, S. asotus, C. herzi, R. brunneus, C. argus were rare specieswhich occupied less than 2.0% in relative abundance. Six species of S. variegatus wakiyae, S. chankaensis tsuchigae, S. gracilis majimae, M. yaluensis, C. herzi and O. platycephala in observed species were known as endemic species. By analyzing of fish community in the surveyed area, the species diversity and evenness of the fishes were high but dominance was low. And the similarity of the fish species among the sites was mid-grade as more than 0.55 in index.

• Korean Journal of Environmental Biology
• /
• v.38 no.1
• /
• pp.30-39
• /
• 2020

The changes in fish stock and biomass before and after fishway renovation located in a Korean estuary were studied and fluctuations in the economic value of the fish resources were estimated. The target fishway located in the east coast area in Korea was renovated in 2014 from the small fish ladder to the ice-harbor fishway. Monitoring was continued for five consecutive years after the renovation(2015 to 2019). Since the renovation of the fish passage, the economic values increased with increases in the fishery resources, except for in 2016 when the drought impact was severe. The yearly average incremental increase in the five years after the renovation was about 227%. The increase in economic value is believed to be due to the increased population of migratory fish as a result of habitat expansion. The exponential rise model showed an increase in economic value with increasing fishery resources (R²=0.896). The model coefficient contributing to economic analysis was 0.582 and the maximum economic value after the renovation was estimated at about 30.4 million. The economic value would be a useful index for quantitative comparison in terms of ecosystem services before and after renovation.

• Korean Journal of Ecology and Environment
• /
• v.37 no.2 s.107
• /
• pp.227-235
• /
• 2004

Fish fauna and community structure were surveyed in the Nakdong River, Gumi City, Kyeongpook province from April 2001 to July 2002. During the surveyed Period, 39 species, 32 genera belonging to 10 families were collected. Cyprinid fish occupied 64.1% (25 species) and cobitid fish had 7.7% (3 species). Fourteen species(35.9%) of observed species were known as endemic species. The exotic fish was Micropterus salmoides (2.5%) . The dominant species were Zacco platypus (relative abundance: 36.7%) and Opsariichthys uncirorstris amurensis (22.7%). Carassius aurafus and Microphysogobio rapidus were numerous (4.0${\sim}$4.3%). The rare species comprising less than 0.15% were Acheilognathus koreensis, Aphyocypris chinensis, Iksookimia longicorpus, Coreoleuciscus splendidus, Rhinogobius giurinus, Sarcocheilichthys variagatus wakiyae, Silurus asotus astus, and Channa argus. It was found that the population density of carnivorous Opsariichthys uncirostris amurensis increased drastically in the mid-reach of the Nakdong river since it had been introduced from the other native rivers in the middle 1990s. Gobiobotia nakdongensis inhabit riffle (water velocity : 0.43${\sim}$0.67 m $s^{-1}$) of which the river bed is mainly sand. This species is considered to be in need of conservation. As the result of analyzing fish community in the surveyed area, the species diversity, evenness and dominant indices were 1.008, 0.663 and 0.196 respectively. The findings showed that the tributary, which the waterside plants were abundant and had various habitats, had a higher species diversity (1.112) than the main river (0.787). Sand mining had been disturbing the river ecosystem of the study stations 3, 11, 13 & 14, and these stations showed a quite low species diversity (0.421 ${\sim}$0.574).

• Korean Journal of Ecology and Environment
• /
• v.44 no.2
• /
• pp.226-238
• /
• 2011

Ichthyological fauna and community structure were surveyed in the Naeseong Stream around the planed Yeongju Dam, Yeongju City, Gyeongsangbuk-do from April 2007 to October 2009, During the survey period, 27 species (25 genera, 10 families) were collected. Cyprinid fish comprised 63.0% (17 species) and cobitid fish comprised 7.4% (2 species). Ten of the 27 species (37.0%) were endemic species. The dominant and subdominant species based on the number of individuals was Zacco platypus (43.2%) and Zacco koreanus (15.8%), respectively. Introduced from the other native rivers and exotic fish were Opsariichthys uncirostris amurensis, Leiocassis ussuriensis, and Micropterus salmoides (11.1%). The declining population density of Zacco koreanus and its subdominant status represents a change, since, up until the mid 1990's, it was widely distributed throughout the area and was the dominant species. The distribution area of Zacco koreanus decreased in size; by 2009, it no longer inhabited the lower reaches of the Naeseong Stream. On the other hand, Zacco platypus remained the dominant species throughout the area, except for the upper-reaches of the water-course. Gobiobotia naktongensis inhabited all areas of Naeseong Stream, which mainly has a sandy bottom. Analyses of the fish community revealed species diversity, even-ness and dominant indices were 0.881, 0.615, and 0.230 respectively. These results showed that the main river, in which the water width and flow are abundant and which has various habitats, has a higher species diversity (0.829) than the tributary (0.735).

• Korean Journal of Environment and Ecology
• /
• v.35 no.5
• /
• pp.490-502
• /
• 2021

This study was conducted to analyze the current status of fish fauna and characteristics of the fish community according to the habitat of Woraksan National Park, Korea. The spatially balanced sampling selected 20 stations from major streams of Woraksan National Park, and three surveys were conducted in each season. The physical environments of the habitat were mostly mountain streams (Aa), with large stones and gravels scattered over the stream. The average altitude of the habitat was 304.4 m, and the average depth of water was 40.3 cm, being less than 1 m in most cases, and the river water level was distributed from 3rd to 5th streams. The principal component analysis of the physical environmental factors by habitat showed that the substrate properties differed according to the altitude. The survey identified a total of 2,183 individuals in 16 species belonging to 7 families. The dominant species was Zacco koreanus(86.2%), and the subdominant species was Rhynchocypris oxycephalus(3.8%). Pseudopungtungia tenuicorpa, classified as the endangered wildlife II, was the first endangered legally protected species found in this survey. Analysis of the rank abundance curve model in the fish community showed the Zipf model at 9 out of 20 points, the Lognormal model in 3 points, and the Preemption model in 4 points. The remaining 4 habitats showed only one species and were not analyzed. The canonical correspondence analysis of 20 stations and fish species was performed to understand the characteristics of the fish community according to environmental factors. The fish communities were divided according to differences in habitat environment by the altitude.

• Korean Journal of Ecology and Environment
• /
• v.38 no.1 s.110
• /
• pp.63-72
• /
• 2005

The fish fauna and community structure were investigated in the Lake Cheongpyeong, Korea, from August 2003 to April 2004. During the period, 43 species belonging 10 families were collected. There were 18 Korean endemic species 41.9%. The five dominant species numerically were A. gracilis (17.4%), Zacco platypus (14.6%), A. yamatsutae (13.2%), Hemibarbus labeo (11.9%), Rhinogobius brunneus (11.7%), and Zacco temmicki (3.0%). The five dominant species in biomass were Erythroculter erythropterus (15.07 kg), H. labeo (13.21 kg), Carassius cuvieri (6.47 kg), A. gracilis (6.05 kg), and Z. platypus (4.71 kg). Of 6 exotic fishes in the lake C. cuvieri, Lepomis macrochirus and Micropterus salmoides were originated from foreign countries but Anguilla japonica, Tridentiger brevispinis, and Chaenogobius urotaenius were introduced from other watershed in Korea.

• Fisheries and Aquatic Sciences
• /
• v.12 no.1
• /
• pp.60-69
• /
• 2009

Fish community structure between eelgrass beds and an adjacent unvegetated area was investigated. Fishes were collected monthly from two eelgrass beds (Gamak and Yeoja Bays) and one adjacent unvegetated area in the southern sea of Korea between February 2006 and February 2007. The number of species for the Gamak and Yeoja Bays were 33, 28, respectively, while 28 species were identified from the unvegetated area. Leiognathus nuchalis was dominant in both Gamak and Yeoja Bays, while Engraulis japonicus was dominant in the unvegetated area. Cluster analysis conducted on total number of individuals for each species produced 3 groups; group A (appeared only in winter regardless of eelgrass), group B (appeared in eelgrass beds during all seasons except winter) and group C (appeared in the unvegetated area during all seasons except winter). The most important differentiating species between eelgrass beds and the unvegetated area were Lateolabrax japonicus, L. nuchalis, Takifugu niphobles and Pholis nebulosa. Based on the results of this study we can assume that eelgrass beds function as a nursery ground for young fishes from spring to fall, but not in winter.

• Korean Journal of Environment and Ecology
• /
• v.28 no.3
• /
• pp.314-325
• /
• 2014

We studied fish fauna at 10 study sites in Ungcheon stream for 4 times from April to October, 2011 to investigate the influence of artificial structures such as dam (with fish-way) and weir (without fish-way), and abandoned mine on fish community. A total of 12 families, 36 species of fishes were collected. Dominant species was Zacco platypus (23.4%) and subdominant species was Zacco koreanus (20.5%). Ten species (27.8%) of Korean endemic species and Micropterus salmoides, exotic species, were observed during the study period. Endangered species of Korea such as Pseudopungtungia nigra and Liobagrus obesus, and Korean endemic species, Coreoperca herzi, which are vulnurable for water quality and had been observed in previous study, were not identified in this study. According to the cluster analysis, Ungcheon stream were divided into three groups consisting upstream (St.1, St.2, St.3), midstream (St.4, St.5, St.6, St.7), downstream (St.8, St.9, St.10). Community structure similarity between upper and lower site of Boryeong dam with fish-way (St.6-St.7) was high, whereas that of weir, lack of fish-way (St.7-St.8) showed little similarity indicating that fish-way was required. According to the canonical correlation analysis, high level of conductivity and salinity at upstream was detected and Misgurnus mizolepis, and endemic species of Korea such as Silurus microdorsalis, Coreoleuciscus splendidus and Iksookimia koreensis were observed at this part of the stream. Since Korean endemic species, Squalidus gracilis majimae cohabit with exotic species, M. Salmoides at downstream whose width is wide and water velocity is low, protection was needed for these endemic species.

• Journal of Korean Society on Water Environment
• /
• v.29 no.2
• /
• pp.196-203
• /
• 2013

Seungchon Weir was constructed in 2010 on the downstream region of Yeongsan River watershed for four major river projects. The purpose of our study was to determine whether fish compositions and distributions differ between the upper ($U_w$) and lower regions ($L_w$) of Seungchon Weir during May - December 2011 along with hydroacoustic fish surveys using Eco-Sounder monitoring ($E_SM$) technique. Total number of fish species sampled by conventional fish sampling at all sites was 29, and 21 and 24 species occurred in the $U_w$ and $L_w$, respectively. Most dominant species was Hemiculter eigenmanni (43%) in the $U_w$ and Opsaiichthys uncirostris amurensis (21%) in the $L_w$, indicating a distinct differences of the species composition. According to hydroacoustic approach of ESM, fish density was significantly higher (p < 0.05) in the $L_w$ section of 250 m than any other sections, This outcome indicates that fishes moving toward the upstream were blocked by weir construction. According to analysis of tolerance guilds, tolerant species (TS) were made of 88% and 79% in the $U_w$ and $L_w$ region, respectively, while the proportions of sensitive species were < 0.1% of the total in the both regions. Trophic guild analysis showed that the proportion of omnivore species were 58% and 40% in the $U_w$ and $L_w$ region, respectively, while insectivores were made of 16% and 21% in the $U_w$ and $L_w$ region, respectively. Both analyses of tolerance guilds and trophic guilds indicate the biological degradation of the waterbody. Fish community structure analysis, based on species diversity, dominance, and evenness indices, showed higher community stability in the $L_w$ region than $U_w$ region. Exotic species of largemouth bass were largely increased in this survey (14%), compared to the past (< 1%), indicating a modification of fish trophic structure.