• Korean Journal of Ichthyology
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• v.13 no.3
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• pp.173-180
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• 2001

The fertilized eggs of Hyporhampus sajori (Temminck et Schlegel) were collected on the shore of Youngil Bay, Phohang-shi, Korea, on May 27, 1991, and were hatched and reared in the laboratory to investigate osteological development of larvae and juveniles. The newly hatched larvae were 7.00~8.50 mm (mean 7.80 mm, n = 5) in total length (TL) and had an ossified cranium, visceral skeleton and shoulder girdle bones. At 8 days, the larvae had attained 10.07~14.75 mm (mean 13.07 mm, n = 5) in TL had elongated dentaries anteriorly, and their vertebral columns were posteriory ossified. At 14 days, the larvae had attained 17.62~19.35 mm (mean 19.20 mm, n = 5) in TL, had ossified pterygiophores, and 41 slender ribs on the vertbrae. At 16 days, the larvae were 18.90~24.72 mm (mean 23.00 mm, n = 5) in TL and had three ossified epurals. Ossification of the jaw bone and operculum of the newly hatched larvae, which was related to feeding and respiration was almost completed 37 days after hatching.

• Korean Journal of Ichthyology
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• v.13 no.1
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• pp.69-73
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• 2001

Observation of morphological changes during larval and juvenile stages of the halfbeak fish, Hyporhampus sajori (Temminck et Schlegel), was made based on samples of fertilized eggs collected on the shores of Youngil Bay, Phohang-shi, Korea, on May 27, 1991, and incubated in the laboratory. During the incubation period, water temperature fluctuated between $17.6^{\circ}C$ and $23.2^{\circ}C$. The newly hatched larvae were elongated and 7.0~8.50 mm in total length (TL) with 40~42+17~18 = 59~60 myotomes. Numerous melanophores were on the head, mid-dorsal part of the body, intestine, and the tail part of the notochord. Three days after hatching the larvae had attained 8.60~10.90 m in TL, had completely absorbed the yolk, and the caudal notochord was flexed $45^{\circ}$ upward. At this time, it was attained postlarvae stage. Thirty-seven days after hatching the postlarvae were 32.37~44.95 mm in TL and had reached the juvenile stage. All fins were formed with a complete set of fin rays with the following counts: dorsal fin rays 16~17; pectoral f in rays 6; ventral fin rays 12~14; caudal fin rays 11~12+11~12 = 22~24.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.79-90
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• 1997

Monthly samples of surf zone fish at Taechon Beach were collected by a beach seine from June 1995 to May 1996, and analyzed for the species composition, abundance and community structure. Of 26 species identified, Favonigobius gymnauchen, Leiognathus nuchalis, Sillago japonica and Kareius bicoloratus predominated in abundance. In spring, the adults of resident species were dominated. A large number of juveniles of pelagic or demersal fish occupied the surf zone from summer to autumn. Fish numbers and biomass were low in winter. The species composition of the present study showed a similar seasonal trend to that obtained in 1984-85. However, demersal fish such as K. bicoloratus, Repomucenus lunatus, Johnius belengerii and Enedrias fangi, and L. nuchalis were increased, while pelagic fish such as Thrissa koreana, Sardinella zunasi and Konosirus punctatus were diminished. These changes seemed to be related to sedimentation of fine particles for demersal fish and subsequent increase in turbidity for pelagic fish after reclamation in the bay.