• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.35-36
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• 2002

제주도 근해는 대마난류, 황해 난류, 황해 냉수, 한국 남ㆍ서해연안수, 중국대륙 연안수 등이 출현하여 이질 수괴들이 시기와 계절별로 복잡한 해황을 형성하여 오징어, 갈치, 고등어, 전갱이, 방어, 삼치 등을 어획하는 좋은 어장을 이루고 있다. 우리나라 연안 해역에서는 오징어를 걸이, 대낚시, 전기식설낚시, 연결식낚시, 로울러낚시, 자동조획기 등으로 어획하고 있으나, 이들은 원줄에 오징어 낚시가 수직식으로 연결되어 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.47-48
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• 2002

바다 속에서의 소음은 해풍, 파랑, 강우 등 자연소음과 어류의 생식음, 신호음, 식이음 등 생물이 내는 음과 선박의 엔진 등과 같은 인공음이 있는데 수중가청음을 이용한 어군의 유집은 어장 조업 시에는 조업 능률을 향상시키고, 축양 어업에서는 음향 제어에 의한 자동급이와 치자어의 육성단계에서부터 음향순치를 통해 어류를 일정한 해역에 정착, 서식하도록 할 수 있어 해양목장화 등 여러 면에 응용이 되어지고 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.246-247
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• 2001

대마난류수, 황해난류수, 황해냉수, 중국대륙연안수, 한국남해안연안수, 혼합수등(노ㆍ平野, 1983; 노ㆍ김, 1983, 노, 1985; 조, 1988, 김ㆍ노, 1994)의 이질수괴가 출현하고 있는 제주도 주변해역은 산업적으로 중요한 어종(조기, 갈치, 고등어, 전갱이, 오징어 등)의 산란ㆍ생육ㆍ섭이장이 되는 어업적으로 상당히 중요한 해역 이며, 또한 이들 수괴들의 경계 역에서의 SST 전선과 고등어 선망어장과의 관계는 연관성이 높은 것으로 나타났다(양 등, 1999). (중략)

• Korean Journal of Ichthyology
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• v.28 no.1
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• pp.57-64
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• 2016

The fish species Uraspis helvola and U. uraspis (family Carangidae, Perciformes) were collected from Korea, and described and compared based on morphological and molecular characters. Uraspis helvola and U. uraspis were clearly distinguished by differences in the beginning point of the straight lateral lines scales (dorsal fin soft rays 12th~13th in U. helvola vs. 15th~16th in U. uraspis), and in the naked area on the breast extends to the pectoral fin base (naked area half way in U. helvola vs. naked area widely connected in U. uraspis). Molecular analysis using 530 base-pairs of mitochondrial DNA cytochrome c oxidase subunit I gene strongly supported the morphological identification. We described it as the new Korean record, and proposed the new Korean name "min-jeon-gaeng-i-sok" for the genus Uraspis, and "heuk-gi-min-jeon-gaeng-i" for the species U. uraspis.

• Environmental and Resource Economics Review
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• v.19 no.4
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• pp.771-804
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• 2010

This paper estimates optimal production of fish stock using discrete time bio-economic model to make zero profits or to maximize economic profits with maintaining sustainable resource levels under an open access and a sole owner. Particularly, this study generates optimal yields and efforts of large purse seine fisheries which catch mackerel and jack mackerel by using the logistic growth function, Cobb-Douglas production function, fisheries cost and profit functions. As a result, optimal yields of mackerel and jack mackerel under ecological equilibrium of a sole owner were approximately 172,512 tons and 16,937 tons respectively. Also, optimal fishing efforts of mackerel and jack mackerel under the same situation were about 8,508 hauls and 4,915 hauls respectively. In conclusion, the paper suggests that the large purse seine should reduce fishing efforts and increase fish stock to generate higher net present value in optimally managed fishery than that of the present large purse seine.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.2
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• pp.128-133
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• 2003

Stimulus effects of strobe light on jack mackerel Trachurus japonicus were studied by measuring the heart rate change according to the different strobe light intensity of 5~75 lx$\cdot$s. Heart rate was observed for 60 min: 10 min before, 30 min during and 20 min after the strobe light stimulus. The measurement of heart rate was repeated three times at 2 hour intervals. The results showed that the heart rate increased during stimulus but temporarily decreased immediately after ending of stimulus. The heart rate changes in both during and after stimulus were decreased with reducing light intensities. The heart rate change according to the repeated experiment was not remarkably different under the lower light intensity

• Journal of Aquaculture
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• v.20 no.1
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• pp.19-25
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• 2007

For establishing a basal diet for the Pacific bluefin tuna Thunnus orientalis (PBT), feeding stimulants were initially identified by omission test using the synthetic extract of horse mackerel, Trachurus japonicus. Four feeding trials were conducted using juvenile PBT weighing $9.0{\pm}0.91\;g$ (trial 1, 2 and 3) and $1.6{\pm}0.23\;g$ (trial 4), which were originated from an artificial seedling production. The fish fed the casein diet with each test solution were added at the ratio of 100 g casein diet to 100 g jack mackerel muscle. A complete synthetic extract of jack mackerel containing all 3 fractions, amino acid, nucleotide and organic nitrogenous base, exhibited a comparable feeding stimulant activity compared to that of natural extract. The omission of nucleotide or amino acid fraction showed lower feeding activity, but the omission of other nitrogenous fraction maintained a similar feeding stimulant activity compared to that of the synthetic extract (trial 1). Inosine-5' monophosphate $Na_2$ (IMP) was identified as a major constituent for maintaining feeding activity. The mixture of L-alanine, L-glutamic acid, L-histidine, L-lysine, taurine and IMP induced a similar feeding activity compared to that of the synthetic extract (trial 2 and 3). In trial 4, the highest feeding activity was finally obtained in the mixture of L-histidine, L-glutamine and IMP, followed by the synthetic extract, the mixture of L-lysine, L-alanine and IMP, IMP and the mixture of L-histidine, L-glutamic acid, L-lysine and L-alanine. These results revealed that the mixture of L-histidine, L-glutamic acid and IMP for the proper feeding stimulant of PBT in this study.

• Korean Journal of Ichthyology
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• v.30 no.3
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• pp.170-174
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• 2018

A single specimen of Caranx melampygus (113 mm standard length), belonging to the family Carangidae, was firstly collected by a set net from the coastal waters of Jejudo Island, Korea. This species is morphologically similar to C. sexfasciatus except for the posterior end of maxilla not reaching the posterior margin of eye (vs. reaching in C. sexfasciatus) and no black blotch on the upper part of opercle (vs. black blotch). We newly add this species to the Korean fish fauna and propose its new Korean name "Jag-eun-ip-jul-jeon-gaeng-i" for the species because it has relatively smaller upper jaw when compared with C. sexfasciatus.

• Korean Journal of Ichthyology
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• v.20 no.2
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• pp.129-132
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• 2008

A single specimen of Carangoides oblongus (133.8 mm SL) belonging to the family Carangidae was firstly collected by a set net from the coastal waters of Jeju Island, Korea. This species resembles Carangoides dinema, but the former is morphologically distinguishable from the latter by lateral line being shorter than straight part, the number of lateral line scutes (37~45 in C. oblongus vs. 20~30 in C. dinema), second dorsal fin rays (20~22 vs. 17~19), and anal fin rays (18~19 vs. 15~17). We newly add this species to the Korean fish fauna and propose its new Korean name "Chae-jjik-yu-jeon-gaeng-i".

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.253-259
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• 1981

A study was made to find out a new method of calculating the survival rate of a fish population from length composition and growth equation. 1. In the steady state of the fish population, let the total mortality rate be z, the age of complete recruitment a, the oldest age in the catch b and the average between the age of complete recruitment and the oldest age in the catch Ut, then we have $$U_{t}\;=\;\frac{a-b\;{e xp}\{-z(b-a)\}}{1-\;{e xp}\{-z(b-a)\}}+\frac{1}{z}{\cdots}{\cdots}{\cdots}{\cdots}{\cdots}$$(1) And let b be infinite, then we obtain $$Z=\frac{1}{U_t-a}{\cdots}{\cdots}{\cdots}{\cdots}{\cdots}{\cdots}$$ (2) 2. Calculating numerical value of $U_t$ from age composition table and growth equation, and substitute in (1) for it, we may obtain the value of z and $e^{-z}$. 3. This method is applied to a case of mackerel and horse mackerel in the coastal waters of Korea, with the following results : Total mortality rate-Mackerel : 0.87909, Horse mackerel : 2.22327, Survival rate-Mackerel : 0.41516, Horse Mackerel : 0.10825, 95 percent confidence Interval of survival rate-Mackerel : $0.35966{\sim}0.47264$, Horse mackerel : $0.06897{\sim}0.14974$