• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.378-384
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• 2007

Some of ecological factors and the early life history of endangered freshwater fish, Pseusobagrus brevicorpus, were investigated to proliferate artificially and to restore the population by release seedlings. The density of population in restricted area by small scale dam was 1.25 ind. $m^{-2}$, and the low capacity for reproduction having 200$\sim$250 eggs ind$^{-1}$. were thought to be a reason of this endangered situation. From the result of induction of natural spawning in aquarium after hormone injection it was considered that the spawning substrate would be aquatic plants with slender branches. The hatching was observed after 50 hrs after fertilization and the larvae showed aggressive behavior. Yolk was almost absorbed 3 days after hatching, and the larvae shaped tad-pole grew up to fry after 30 days. We discussed on the strategies for conservation of this species according to those results from investigation on ecology and early life history.

• Korean Journal of Ichthyology
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• v.31 no.2
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• pp.101-109
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• 2019

This study investigated the characteristics of fish communities at the Lake Yedang, in 2013 to 2014 and 2017. During the survey period, there were 29 species of 10 families collected from 3 survey stations. Of them, Cyprinidae occupied 34.5% (14 species), Bagridae, Gobiidae 10.3% (3 species), and Cobitidae, Centrachidae were 6.9% (2 species) in the number of species, respectively. Korean endemic species were 4 species (13.8%) Abbottina springeri, Cobitis nalbanti, Pseudobagrus koreanus, Odontobutis interrupta and accounted for a low rate. There were 3 species (10.3%) exotic species including Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides. As a result of community analysis, dominant index was 0.45~1.00, diversity index was 0.19~2.30 and richness index was 0.41~1.94.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.823-833
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• 1997

To clarify the annual reproductive cycle of the banded catfish, Pseudobagrus fulvidraco (Richardson), the seasonal changes in histological aspect of gonad and liver were examined. The adult fish was raptured from the upper stream of Young-San river, Chunnam in each month from May 1992 to June 1993. Based on the annual changes in GSI (gonadosomatic index), HSI (hepatosomatic index), CF (condition factor) and histological aspects of the gonads, the annual reproductive cycle were classified into 5 periods as follows: 1) Growing phase (from April to early May): The value of GSI increased and the size of oocytes in perinucleolus stage in oocytes increased gradually. Spermatogonia were developed actively from the epithelial tissues of seminiferous tubules. 2) Maturing phase (from Hay to early June): GSI levels increased rapidly in both sex. Oocytes at various developmental stages were observed. Appearance of active spermatogenesis were observed. 3) Mature and spawning phase (from June to August): High values of GSI remained static and oocytes accumulated significant quantitis of yolk globules. 4) Degenerating phase (from September to November): GSI levels decreased and ovaries were filled mostly with oocytes at the perinucleolus stage. Hepatic cells accumulated significant amounts of lipid droplets. 5) Resting period (from December to March) : Low values of GSI were kept and the size of oocytes at the perinucleolus stage did not increase. Spermatogenesis was not observed.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.665-679
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• 2015

Yearly mean temperature in the 29 lakes surveyed ranges from 12.6 (Suncheon) to 13.9℃ (Mokpo), the lowest in −2.7℃ (January) and the highest in 25.9℃ (July). Monthly mean the amount of rainfall recorded the highest of 336.7 mm in August and the lowest with 4.9 mm in January. A total of 424 species of phytoplankton were identified. They were 157 Chlorophyceae, 161 Bacillariophyceae, 39 Cyanophyceae, and 67 other algal taxa. The phytoplankton diversity were low in stream type reservoirs such as Guemho, Youngsan and Youngam. The population density of phytoplankton ranged from 19 to 53,161 cells/ml. Annual mean of total zooplankton abundance in 45 sites was 369±827 ind./L (n=180). Rotifers were the most common taxa and their relative abundance was high (65~77%). The benthic microinvertebrate fauna of 10 reservoirs of Jeonnam province were 71 species of 61 genera of 44 families of 16 orders of 7 classes of 4 phyla. Aquatic insects of Phylum Arthropoda were 50 species of 44 genera of 28 families of 6 orders. The number of individuals was 6,132. Diptera was highiest (41.3%), and Ephemeroptera (31.0%), Trichoptera (17.5%), Anellida (3.8%), Mollusca (3.3%), Crustacea (0.4%). Large hydrophytes were identified 32 taxa, 2 varieties 30 species 26 genera and 20 families. Especially, Jijung and Juam lakes require management such as physical remove of this ecosystem disturbance field plants. Fishes were identified total 44 taxa, such as 25 Cyprinidae (56.8%), 8 Cobitidae (17.0%), 3 Gobiidae (6.4%), 2 Bagridae (4.3%), 2 Osmeridae (4.3%), 2 Odontobutidae (4.3%), 2 Centrachidae (4.3%), 1 Siluridae (2.1%), and 1 Centropomidae (2.1%). A pale chub was dominant species (18.9%).

• Applied Microscopy
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• v.28 no.1
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• pp.39-48
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• 1998

The spermatozoa of bagrid catfish, Pseudobagrus fulvidraco are approximately $76{\mu}m$ in length, and a relatively simple and elongated cell composed of a spherical head, a short middle piece and a tail. The ultrastructure of spermatozoa of P. fulvidraco is characterized by the following features. The acrosome is absent as in most teleost. The round nucleus measuring about $1.67{\mu}m$ in length and diameter is depressed with a deep nuclear fossa. The nuclear fossa, the length of which is about three-fifths of the nuclear diameter, contains the proximal and distal contrioles. The two centrioles are oriented approximately $160^{\circ}$ to each other. The filamentous materials give rise to satellite appendages arranged tangentially from the triplets of the distal centriole and the doublets of the anterior end of the axoneme toward the nuclear envelope. The mitochondria are not fused and their number is 20 or more. They are arranged in two or three layers and two rings within the cytoplasmic collar and surround the axoneme. They are separated from the axoneme by the cytoplasmic canal. The axoneme is of the 9+2 microtubular pattern and has inner but no outer dynein arms. The two lateral fins are in the same plane with the two central microtubules, the doublets 3 and 8, which are ultrastructural characteristics of the sperm tail unlike other siluroids lacking the lateral fins.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.271-278
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• 2010

Field monitoring was conducted for fish fauna and community assessment at 7 sites from April 2008 to October 2009 in the Chogang Stream. The number of fish samples in this period were 4,669 in 36 species of 9 families. Family Cyprinidae take 66.7 (24 species), Cobitidae, Bagridae, Centropomidae and Odontobutidae occupied 5.6%(each 2 species), respectively. Twenty species (55.6%) including Acheilognathus koreensis and A. yamatsutae were found endemic out of the 36 species. The species of Pseudopungtungia nigra, Gobiobotia macrocephala and Gobiobotia brevibarba were endangered species. The most frequently found one was Zacco koreanus (34.0%, n=1,588) followed by Z. platypus (22.6%, n=1,053) and Coreoleuciscus splendidus (13.3%, n=623). The lower reach of Chogang Stream was more abundance of species, high diversity, evenness and richness, and lower dominance index than those of the upper reach. According to the dendrogram established at 0.5 level of similarity rate, sampling stations were divided into 3 groups. They were divided into upper most stream (St. 1~St. 2), upper stream (St. 3), middle and lower stream (St. 4~St. 7). Overall, it was concluded that the Chogang Stream has been relatively well protected from the anthropogenic disturbance for the legally protected species including the endemic species studied in this study.

• Korean Journal of Ichthyology
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• v.2 no.1
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• pp.63-76
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• 1990

Studies on the microdistribution, distributional aspect and affinity of Korean endemic species, SHIRl, Coreoleueiseus splendidus in th southern half of the Korean peninsula were carried out from May, 1966 to November, 1989. This species was found in 14 independent rivers and streamlets of the south Korea ; Yimjin R., Han R., Kum R., Ungchun S., Mangyung S., Dongjin R., Somjin R., Kwangyang East S., Sachun S., Gonyang S., Nakdong R., Samchukosip S., Samhwa S. of Namhae Island and Guchun S. of Geojae Islands, and were not found from Youngsan R., Ansung S. and Sabgyo S. This species was not common and independent comprising less than 25% of the total fish population in all habiting sites. Distributional zone was in the middle or upper streaches of main streams and tributaries. The average slope of distributional zone was 2.6, minimum slope was 0.29 and maximum slope was 5.56. Thirty-three species were found to occur along with this fish and 10 species of them occurred with more than 50% frequency. They were; 20 sp. of Cyprinidae, 5 sp. of Cobitidae, 1 sp. of Salmonidae, 1 sp. of Bagfridae, 1 sp. of Siluridae, 2 sp. of Amblycipitidae, of Serranidae, and 1 sp. of Eleotridae. Some species of fish appeared to have the same ecological position even though they have different distributional zones. These species were as follows; Acheilognathus signifer and A. limbata, Micriophsogobio koreensis and M. yaluensis in Cyprinidae, Cobitis koreensis, C. longicorpus, C. rotundicaudata in Cobitidae, Liobagrus andersoni and L. mediadiposalis in Amblycipitidae.

• Korean Journal of Ichthyology
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• v.13 no.1
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• pp.40-49
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• 2001

The ichthyofauna and fish community of the Dongjin River system were surveyed at 21 sites from October 1998 to September 1999. We confirmed the presence of 53 species in 14 families belonging to seven orders. Thirty-two species of cyprinid fishes accounted for 60.4% of the total, four species of cobitid and gobiid fishes 7.5% of the total, and two species of bagrid and centrarchid fishes for 3.8% of the total. The dominant species in the Dongjin River system was Zacco platypus (relative abundant 26.0%), the subdominant species was Carassius auratus (14.7%). The dominant and subdominant species in each stream of the Dongjin River system were determined. In the Dongjin River, the dominant species was Z. platypus (40.6%), the subdominant Acheilognathus lanceolatus (20.5%); in Wonpyeong stream, Pseudorasbora parva (22.6%) and Hypomesus olidus (13.2%); in Gobu stream C. auratus (67.5%) and Cyprinnus carpio (15.4%). Fourteen of the 53 species from the the Dongjin River system comprised 28.6% of the total Korean endemic species; seven rare species accounted for less than 0.1% of the total. Four exotic fish species were found: Cyprinus carpio (Islaeli carp), Carassius cuvieri, Micropterus salmoides and Lepomis macrochirus. The species dominance, diversity, and evenness index of the fish community from the Wonpyeong stream were 0.12, 1.08, and 0.91, respectively, indicating better conditions than those of the Dongjin River and the Gobu stream. The fish community of the Wonpyeong stream showed closer relationship to that of the Dongjin River than to that of the Gobu stream.