• Korean Journal of Ichthyology
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• v.30 no.4
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• pp.217-223
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• 2018

The study on the spawning ecology of Sarcocheilichthys variegatus wakiyae at Jicheon stream, Korea was investigated from March 2016 to February, 2017. The sex ratio of male to female was 1 : 0.97 and there was no significant difference. The spawning season was from the end of April to the mid-July, and the peak of spawning period was from the beginning of May to the end of June. The average water temperature at this time was $18^{\circ}C$. According to frequency analysis of total length, it is presumed that the group with a total length of less than 51~70 mm was one year old, the 71~100 mm was two years old, and the group over 101 mm was three years old. They sexually matured when they were over two years. The average number of eggs in the ovaries was estimated as $428{\pm}194per$ matured female. The mature eggs were yellowish, oval, and had a mean diameter of $2.38{\pm}0.25mm$ and a short diameter of $1.98{\pm}0.20mm$.

• Korean Journal of Ichthyology
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• v.30 no.2
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• pp.92-99
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• 2018

Feeding ecology of endangered Korean endemic miho spine loach, Cobitis choii, was investigated in Jicheon Stream, Geumgang River, Korea to provide ecological characteristics and baseline data for its restoration. C. choii is active during daylight hours above sand from March to October when the water temperature exceeded $13^{\circ}C$, but tended hibernate in the stream bottoms (sand) in the winter months (November~February) when the water temperature was lower than $13^{\circ}C$. They fed (index of relative importance, IRI) mainly Diptera (69.9%), Copepoda (23.2%), Arcellidae (2.3%), Branchiopoda (2.0%) and Ploima (2.0%). And their small juvenile (age 0+) fed mainly small size, Ploima and Branchiopoda, however, they ate mainly large size, Chilonomidae, while growing to adult fish (age 2+~3+).

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.252-261
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• 2021

The egg development and early life history of short barbel gudgeon Squalidus japonicus coreanus were investigated. For the experiments, the mature adults were collected at the stream Jicheon in Korea. The eggs from the females were obtain by injecting 10 IU/g of human chorionic gonadotropin and inseminated by wet method in the laboratory. The fertilized eggs were 1.12±0.03 mm (1.10~1.16 mm, n=30) in diameter. The embryo began to hatch about 49 hrs after fertilization under water temperature of 23±1℃. The newly-hatched larvae (Yolksac larva) were 3.7±0.1 mm (3.4~3.8 mm, n=16) in total length, and they haven't Melanophore. 5 days after hatching, the Preflexion larva were 5.3±0.2 mm (5.0~5.5 mm, n=16) in total length, and they began to eat a Rotifer. 19 days after hathing, the Flexion larva were 6.0±0.3 mm (5.4~6.5 mm, n=16) in total length, and they began to eat a Brine shrimp. 29 days after hatching, the Postflexion larva were 9.6±0.5 mm (8.3~10.5 mm, n=16) in total length, and dorsal fin rays are were formed. 44 days after hatching, the juvenile were 15.5±1.0 mm (13.5~17.0 mm, n=16) in total length, and all their fin-rays were formed.