• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.646-653
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• 2003

Investigations were made on the population structure, sex ratio, growth, and recruitment patterns of Leptochela sydniensis in the southwestern coastal areas of Korea, between May 2000 and December 2001. Spawning period, fecundity, brood loss, reproductive output, and size at sexual maturity also were examined. The results of the sex ratio showed that females were more numerous than males during the overall study period. Parameters of growth were estimated using the modified von Bertalanffy growth function (VBGF) model incorporating seasonal variation into growth. Females grew somewhat faster and reached a larger size than males $(L\infty=12.80\;mm\;CL\;and\;K=0.70\;yr^{-1}\;or\;females,\and\;L\infty=12.08\;mm\;CL\;and\;K=0.69\;yr^{-1}$ for males). The structure of recruitment patterns obtained by the FiSAT program indicated one normally distributed group. Based on the occurrence of ovigerous females and the gonadosomatic index (GSI), the main spawning season was from June to August. Analysis of covariance indicated that brood loss was not observed during the incubation period. The size at which $50\%$ of females are mature is estimated as 5.48 mm CL.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.378-382
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• 2011

The feeding ecology of bluefin searobin Chelidonichthys spinosus around Jeju Island was examined. Specimens were caught every autumn from 2004 to 2007. The primary prey items of C. spinosus included fish, shrimp, and crabs. Chelidonichthys spinosus preyed upon a wide range of sub-pelagic crustacean groups(e.g., Leptochela gracilis, Leptochela sydniensis). This species was also an opportunistic feeder, exploiting the available prey groups in each area(i.e., L. gracilis in the South Sea and East China Sea groups and L. gracilis and L. sydniensis in the Yellow Sea group). The main prey group of this species changed from demersal shrimp to pelagic shrimp with prey environmental changes. Observed ontogenetic shifts in diet were relatively clear despite substantial overlap between the 10 cm and 20 cm C. spinosus groups.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.222-223
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• 2002

돗대기새우류(Leptochela sp.)는 전 세계적으로 2아속 12종이 분포하고 있으며 이중7종이 인도태평양 해역에 분포하고 있다. 우리나라 연안해역에서는 돗대기새우 (L.gracilis)와 둥근돗대기새우(L. sydniensis) 2종이 보고되고 있으며 특히 봄과 가을에 대량 출현한다. 돗대기 새우는 젓새우류와 혼획되어 어획되며 서남 해역에 어가의 주소득원이 되고 있다. 지금까지 보고된 연구는 형태학적 분류 (Chace, 1976), 성장 (Park and Lee, 1995)과 2차 성징의 특성 (Park, 1984)에 관한 연구 등이 있다. (중략)

• Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.240-248
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• 2009

Distribution and abundance of planktonic shrimps were studied in the southern sea of Korea from 1987 to 1991. Nine species of five genera belonging to three families were identified. Of these, Leptochela sydniensis and Lucifer intermedius were predominant species and Lucifer penicilifer and Lucifer typus were common species. Remaining five species, Acetes chinensis, Leptochela gracilis, Lucifer chacei, Process wheeleri and Sergestes similis occurred sporadically and rarely. The distribution pattern of planktonic shrimps varied with species and sampling periods. L. intermedius occurred abundantly along inshore waters. L. penicilifer and L. typus appeared in both inshore and offshore waters, but more abundantly in offshore waters under influence of the Tsushima Current. In conclusion, the distribution patterns of planktonic shrimps may be related with hydrographic characteristics and seasonality in the southern sea of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.1
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• pp.32-38
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• 2008

We studied the feeding habits of Sebastes thompsoni based on 421 specimens obtained in monthly collections between January and December 2005 in the coastal waters off Busan, Korea. S. thompsoni was a crustacean feeder, and consumed mainly shrimp and euphausiids. Its diet also included small quantities of amphipods, cephalopods, and fish. It showed distinct ontogenetic changes in feeding habits. Smaller individuals (14-17 cm standard length (SL)), mainly consumed euphausiids. The portion of these prey items decreased with increasing fish size, and larger individuals (>20 cm SL) consumed mainly shrimp such as Leptochela sydniensis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.372-377
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• 2011

The feeding habits of the redbanded searobin Lepidotrigla guentheri were studied using 186 specimens collected from September to November, 2006, in the coastal waters off Gori, Korea. The sizes of L. guentheri ranged from 7.1 to 16.7 cm total length(TL). L. guentheri is a bottom-feeding carnivore that consumes mainly shrimp, especially Leptochela sydniensis, amphipods, and crabs. Its diet also includes small quantities of stomatopods, mysids, cumaceans, euphausiids, polychaetes, and copepods. Our feeding-strategy graphical method reveled that L. guentheri is a specialized feeder, with a narrow niche width. L. guentheri mainly consumed shrimp of all size classes and did not show significant ontogenetic changes in feeding habits. Smaller individuals(7-11 cm TL) secondly consumed amphipods, with the portion of amphipods in the total diet decreasing as body size increased. Prey size increased significantly as the fish grew in size.