• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.480-487
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• 2012

This study was conducted to search the effects of debris barrier on the benthic macroinvertebrate. Gimcheon was selected as the survey site as it has relatively stable ecosystem with constantly running water. The survey was conducted 6 times before and after the construction of debris barrier from February in 2009 to October in 2010. In the first survey before construction, the identified species were 36 species belonged to 22 families, 9 order, 4 class, and 4 phylum. The figure slightly decreased to 30 species belonged to 18 families, 7 order, 2 class, and 2 phylum in the sixth survey after construction. Before construction, occupation ratio of EPT taxa was showed in the following order: Ephemeroptera (50.0%, 85.0%), Trichoptera (35.3%, 10.0%), and Plecopteran (14.8%, 5.0%). After construction, it was showed in the following order: Trichoptera (50.3%, 68.0%), Ephemeroptera (42.1%, 29.4%), and Plecopteran (7.5%, 2.7%). Ephemeroptera was the highest before construction. Trichoptera increased rapidly after construction. The Diversity, Richness, Evenness, and Dominance indices were all turned low in the second survey right after the construction. However, each index tended to increase with the course of time. In Functional Feeding Groups, GC type was the highest of 60.7% before construction. After construction, SC(53.1%) and FC(35.4%) increased rapidly and they became stabilized since the third survey. The result of this study reveals that debris barrier greatly affects the Aquatic Ecosystem right after its construction, but the system becomes stable and returns to normal with the course of time (about 18 months). Therefore, the study considering various influence factors such as time is required to recover completely through further long-term monitoring.

• Korean Journal of Ichthyology
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• v.19 no.3
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• pp.236-245
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• 2007

Feeding habits of Liobagrus andersoni were investigated in a tributary of the Namhan river from October 2005 to October 2006. L. andersoni was considered as an entirely bottom-feeding carnivore based on it's stomach contents. Because, the diet of L. andersoni was mainly aquatic insect such as Ephemeroptera, Trichoptera, Diptera. The most important prey was Ephemeroptera species. Small sized individuals (<50 mm SL) fed mainly on small prey organisms such as Baetis. However, larger Ephemeroptera and Trichoptera were heavily selected with increasing fish size. The relative proportion of food items was changed with season. The prey materials were more various at summer and autumn than winter. L. andersoni eaten Ephemeroptera intensively in spring and summer but eaten Trichoptera and Chironomidae in winter. Feeding activity of L. andersoni was started after sunset and was most active at midnight, but the activity was reduced after sunrise and during day period. So it was considered that L. andersoni was a nocturnal stalkers.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.278-286
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• 2021

The habitat characteristics and feeding ecology of the Siberian stone loach Barbatula toni were investigated in Bukcheon (Stream), Eocheonri, Ganseong-eup, Goseong-gun, and Gangwon-do, Korea from January to December 2013. B. toni lived in rapids or slow rapids from the upper stream to downstream, with the largest number of inhabitants in the middle-downstream regions. As a result of analyzing habitat preferences by age, 0+ and 1+ to ≥3+ showed differences. Ages of 0+(juveniles) lived mainly in rapidly flowing water (37.6±26.79 cm/sec) and low water depths (13.3±9.47 cm) in the pebble bottoms (substratum particle size 9.5±6.66 cm), but ages 1+ to ≥3+ lived mainly in relatively slowly flowing water (13.3±17.33 cm/sec) and relatively deep depths (25.9±10.31 cm) in stone and large stone bottoms (substratum particle size 18.0±7.63 cm). B. toni was mainly eaten from March to December when the temperature was above 5℃, and the amount of food eaten peaked in June and October. Their main food sources analyzed by the index of relative importance (IRI) included Diptera (57.0%), Ephemeroptera (29.3%), and Trichoptera (13.5%). The juveniles (age 0+) fed on small-sized prey such as Diptera and Trichoptera whales, but as they grew, they mainly ate large-sized Ephemeroptera. These feeding habits and changes in food according to the growth of B. toni were very similar to those of sibling species, B. nuda.

• Korean Journal of Environment and Ecology
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• v.37 no.3
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• pp.198-208
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• 2023

This study collected samples of Korean dark sleepers (Odontobutis interrupta) in the Keumdang Stream from March to November 2021 to investigate their feeding habits. The sizes were classified by age (1 year and 2 years old, and 3 years or older). The food organisms of O. interrupta included Isopoda, Amphipoda, and Decapoda of the Malacostraca, Ephemeroptera, Odonata, Hemiptera, Plecoptera, Coleoptera, Diptera, and Trichoptera belonging to the aquatic insect of Arthropoda (accounting for 86.6% of the population), Tubificida, Haplotaxida, and Rhynchobdellida belonging to the Clitellata of Annelida (accounting for 7.3%), Systellommatophora and Mesogastropoda belonging to the Gastropodo of Mollusca (accounting for 2.8%), fish (accounting for 3.3%), and fish eggs. Korean dark sleepers fed mostly on aquatic insects, fish, crustaceans, and annelids. Aquatic insects were the most important food source, with 70.1% of the population, 31.7% in biomass, and 72.6% in the index of relative importance. Korean dark sleepers were carnivorous in diet and belonged to the stalker in food intake characteristics and forms. A food migration was observed since less Diptera was found, and more fish, Decapoda, Trichoptera, and Odonata were found in the biomass of the feed consumed by larger species. Diptera (65.3%), Haplotaxida (14.5%), Ephemeroptera (7.0%), Diptera (58.6%), Ephemeroptera (24.5%), fish (4.8%) Diptera (30.1%), Ephemeroptera (20.4%), Isopoda (13.3%) were mainly fed in the autumn.

• Korean Journal of Ichthyology
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• v.35 no.1
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• pp.30-38
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• 2023

The feeding ecology of the eight barbel loach, Lefua costata, were investigated in the Jusucheon (Stream), Namyang-ri, Okgye-myeon, Gangneung-si, Gangwon-do, Korea from January to December 2013. L. costata mainly fed from March to December when the water temperature was higher than 5℃, and the feeding rate peaked in April~May and September~October. Their main food organisms analyzed by the index of relative importance (IRI) were Diptera (77.1%), Ephemeroptera (20.3%), Trichoptera (1.7%) and Odonata (0.4%) in Insecta. Other food organisms were various, such as Arhynchobdellida (0.6%) and Tubificida (0.1%) of Annelida, Nematoda (0.2%), fish (Actinopterygii, 0.1%), and Veneroida (0.01%) of the Mollusca. Major seasonal food organisms were Diptera (55.4%) and Ephemeroptera (41.6%) in spring, Diptera (92.7%) and Anelida (6.8%) in summer, Diptera (70.8%), Ephemeroptera (9.0%), Trichoptera (8.1%) and Annelida (7.7%) in autumn. By age, juvenile (0+) tended to eat only Diptera (mainly Chironomidae, 98.2%) that were relatively small in prey size. However, as it grew, the proportion of Diptera gradually decreased, and the proportion of relatively large Mayflies and Annelids increased. The size of the prey organisms showed rapid growth, with 2.5±1.05 mm for juvenile (0+), 3.2±1.29 mm for one year (1+), 3.7±2.05 mm for two years (2+), and 6.8±4.97 mm for three years or more (≥3+).

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.162-167
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• 2010

Ecological characteristics of Orthrias nudus from the Eoron Stream, Gangwon-do, Korea were investigated from January to December 2009. O. nudus inhabits mainly riffles of the upstream and mid-upstream stretches of Eoron Stream, which were composed of boulder and cobble bottoms. The current velocities in these habitats were 0.42~1.34 m/sec and depths were 15~46 cm. The sex ratio of female to male was 1 : 0.98. It is presumed that the spawning season is from April to June when water temperatures were $15{\sim}19.2^{\circ}C$. Sexually mature individuals appeared to be over one year of age. Frequency analysis of total length indicated that the group 58~99 mm in total length is represented by one-year-old individuals, and the group over 100 mm by two-year-old individuals. The average number of eggs in the ovaries was estimated as 4,119 per mature female. Stomach contents of O. nudus were composed of aquatic insects such as Ephemeroptera, Trichoptera and Diptera.

• Journal of Wetlands Research
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• v.2 no.2
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• pp.133-146
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• 2000

An ecological survey was performed in Miryang dam water system during the period of June 5~6, 2000. The fauna collected from 7 sites consisted of total 67 species, 49 genus, 25 families, in 7 orders of aquatic insects. These included 29 species of Ephemeroptera, 22 species of Trichoptera, 7 species of plecoptera, 6 species of Diptera, 1 species of Megaloptera, Odonata and Coleoptera repectively. The relative abundance of Ephemeroptera, Trichoptera, Plecoptera, Diptera, and Coleoptera was 71 %, 11.2%, 5.1%. 11.9% and 0.6% respectively. The primary dominant species of tatal level was Epeorus aesculus, and second dominant species was Epeorus latifolium. The primary dominant species were Heptagenia kihada at site 1, Ecdyonurus dracon at site 2,3,4 and Epeorus aesculus at site 5, Epeorus latifolium at site 6,7. Dominance indices were ranged from 0.30 to 0.55, and species diversity indices from 3.11 to 4.25(mean=3.71). Saprobic system based on species diversity indicated that whole sites were oligosaprobic.

• Korean Journal of Ichthyology
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• v.31 no.1
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• pp.54-61
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• 2019

A study on the diel activities and feeding habits of Pseudobagrus brevicorpus living in the Daegacheon Stream of Nakdonggang River was conducted in September 2017. Diel activity took place during the night, just after sunset and just before sunrise. Pseudobagrus brevicorpus swam in the middle depths, and when they found prey organisms, approached and consumed them immediately. Fish were divided by age into three groups. Prey organisms whose index of relative importance in the stomach contents exceeded 1% belonged to the orders Ephemeroptera (80.8%), Diptera (8.6%), and Trichoptera (8.5%). An index of relative importance by age showed that the Ephemeroptera are very important prey organisms, and the sizes of prey organisms increase with fish growth.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.153-154
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• 2003

Trichoptera, or caddisflies, comprise one of the major aquatic insect orders. Like Lepidoptera, caddisflies are capable of spinning silk from specially modified salivary glands, and the diversity of ways this silk is used probably accounts for the success of the order as a whole. These utilize silk to construct both larval and pupal shelters, often incorporating materials from the environmental among the silk thread. In this study, we try to find and characterize novel type genes that should be translated to major component protein of aquatic silk. (omitted)