• Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.43-52
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• 2007

The relationships among long-term climatic change in the southern part of the Korean peninsula, oceanic conditions of the South Sea, Korea, and winter catches of major small pelagic fishes were analyzed using 33 years of time-series data from 1971-2003. In the early 1990s, winter climatic conditions in the southern part of the Korean peninsula shifted to a warmer regime with higher air temperature, weaker wind speed, and lower relative humidity. Also, winter sea surface temperature (SST) became consistently higher in the South Sea. The annual catch of major small pelagic fishes in the South Sea increased dramatically in the mid 1990s, whereas the catch of total fishes decreased in the late 1980s. In particular, the winter catch started to increase markedly in the late 1980s, and has remained over 120,000 M/T since the late 1990s. Correlation analysis of the winter catch of major small pelagic fishes and environmental factors showed that catch was correlated with air temperature (r=0.468, P< 0.01), wind speed (r=-0.732, P< 0.01), relative humidity (r=-0.73l, P< 0.01), and SST (r=0.672, P< 0.01). Multiple regression analysis between the winter catch of major small pelagic fishes (Y) and environmental factors (X) resulted in the equation: $Y=-0.017-0.217\;X_3-0.486\;X_4+0.325\;X_5(R^2=0.754,\;P<0.000)$.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.3
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• pp.451-458
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• 2009

The purpose of this study is to analyze the nutrition composition and physiological changes, and to evaluate the food quality of live fish in cultured and wild fishes which have been kept in an aquarium tank. The moisture and lipid content of wild and cultured fishes when kept in an aquarium tank for seven-days storage was found to be lower than those of the initial stage storage(zero day). The breaking strength was also rapidly decreased in all of live fishes tested in this study as the periods of storage extended. The protein content did not differ significantly. However, the content of cortisol, which is a indicator indicating a stress reaction in tissues, was apt to increasing as the periods of storage extended. The cortisol content of wild fishes were higher than those of cultured fishes. On the other hand, the activity of activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), which is also a indicator indicating a stress reaction, were not changed in the serum of wild and cultured fish, suggesting the ALT and AST activity dose not directly related with a healthy loss originated from stress. The death ratio of wild fishes were higher than cultured ones due to limited activity and stress during the storage in a aquarium tank.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.1
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• pp.81-88
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• 2018

A study for species composition and abundance of the fish assemblages in the eastern Jinhae Bay, Korea was conducted using monthly larval collection by a RN80 net from October, 2010 to September, 2011. Of all the 45 species collected, the dominant species were Clupea pallasii, Hexagrammos otakii, Pholis fangi and Engraulis japonicus. Clupea pallasii, Hexagrammos otakii, Pholis fangi in winter and examined Engraulis japonicus, Acanthogobius sp., Parablennius yatabei, and Tridentiger trigonocephalus in summer appeared seasonally. Popoulation characteristic by stations was not clear seasonally and spatially, and appearance aspects of dominant species were similar by stations. Compared our results with other studies in the South Sea, dominant species and their appearance period were similar to their spawning period. Finally, the appearance period of the larvae in the South Sea was closely resulted to spawning period rather than the regional characteristic.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.265-271
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• 2015

The feeding habits of Okamejei kenojei were studied using 242 specimens collected from October 2010 to September 2011 in the coastal waters of Gadeok-do, Korea. O. kenojei was carnivorous feeder that consumed mainly shrimps, crabs, and fishes. Its diet also included small quantities of stomatods, cephalopods, amphipods. The size of O. kenojei ranged from 10.4 to 47.4 cm in total length (TL). O. kenojei showed ontogenetic dietary shift. <15.0, 15.0-19.9 cm size classes fed mainly on shrimps and amphipods. 20.0-24.9 cm size class fed mainly shrimps and crabs. Thereafter, shrimps and crabs were decreased with ontogenesis while fishes and cephalopods were increased. Increasing size, the mN/ST were constantly decreased, but mW/ST were constantly increased.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.3
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• pp.169-175
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• 2007

To examine the mesh selectivity and optimum mesh size of gill nets for silver promfret Pampus argenteus, the field experiments were carried out during June 27th to July 3rd, 2005 at the coastal area of Imja island. The experimental gill nets for silver promfret were used in two set, which one set was consisted of 12 sheets, and each set was connected alternatively four defferent sheets those were 141mm, 148mm, 155mm and 164mm in mesh size. The analysis of mesh selectivity curve was done by Kitahara's method. The total number of fishes caught by experimental fishing of gill nets for silver promfret was 1,409, and it was consisted of 1,022 silver promfrets(72.5%), 123 croakers(8.7%), 70 red tongue soles(5.0%), 67 blue crabs(4.8%), 22 red seabreams(1.6%), and 105 other fishes(7.4%). The number of fishes caught by the mesh size was 244 at mesh 141mm(mean 6.8/sheet), 261 at mesh 148mm(mean 7.3/sheet), 295 at mesh 155mm(mean 8.2/sheet) and 222 at mesh 164mm(mean 6.2/sheet). The body weight of fishes caught by the mesh size was 102.1kg at mesh 141mm(mean 2.8kg/sheet), 112.9kg at mesh 148mm(mean 3.1kg/sheet), 132.8kg at mesh 155mm(mean 3.7kg/sheet), and 100.4kg at mesh 164mm(mean 2.8kg/sheet). The value of maximum l/m on mesh selectivity curve and the value of l/m on the selection range of 50% was estimated at 1.91 and from 1.63 to 2.23, respectively. Therefore, the optimum mesh size of gill nets for silver promfret was estimated 135mm, and the total length at the selection range of 50% was from 220mm to 301mm. But, it will be useful to use the mesh size of gill nets which is about 10-15% larger than the estimated optimum mesh size of gill nets considering the number of fishes caught, body length and body weight etc.

• Korean Journal of Ichthyology
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• v.13 no.4
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• pp.267-273
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• 2001

This study investigated consignment quantity and value of marine fishes consigned in Kunsan Harbor from 1993 to 1999. The total quantity of fishes consigned over seven years period was 194,531 tons (t), of which 31,632 t (16.3%) in 1994 was the largest, while 25,956 t (13.3%) in 1997 was the smallest. The total consignment value was 367,352,125 thousand won, of which 63,221,365 thousand won (17.2%) in 1996 was the highest, and 38,835,400 thousand won (10.6%) in 1999 the lowest. The group of fish that held the largest weight of consignment sale in Kunsan Harbor was croakers; their consignment quantity was 21,217 t. or 10.9% of all fishes, and their consignment value was 112,768,637 thousand won which is 30.7% of the total value. Fishes consigned in Kunsan Harbor were of great significance in the regional economy, as they comprised 74.7% of the consignment quantity and 76.4% of the consignment value of all marine fishes in Jeollabuk-do, although they came under very low weight as 3.1% of the consignment quantity and 4.2% of the consignment value of the total consignment sales of Korea.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.305-312
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• 2023

Diet composition and feeding strategy of the largehead hairtail, Trichiurus japonicas were studied using 375 specimens collected by purse seine, set net fisheries and lure fishing from February 2021 to January 2022 in the southern sea of Korea. The anal length (AL) of these specimens was from 3.4~49.0 cm. T. japonicus fed majorly on Fishes (especially Engraulis japonicus) based on ranking index (%RI=99.3). Fishes were the main prey items for all size classes. T. japonicas also showed size-related dietary shift from E. japonicus to T. japonicus, Larimichthys polyactis and Engraulidae. Fishes were the main prey items for all seasons. The main fish prey during spring and summer was E. japonicus, but in the autumn and winter, the E. japonicus portion decreased, and T. japonicus, L. polyactis, and Engraulidae portion increased. T. japonicus were specialized feeders with E. japonicus as their dominant prey.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.227-233
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• 2013

A total of 25 species, 3,880 individuals and 3,145.1 g of fishes were collected by a surf net from the eelgrass bed in Minyang. Most fishes collected in the eelgrass bed belong mainly to small fish species or juveniles. The dominant fish species were Gymnogobius heptacanthus, Rudarius ercodes, Pholis nebulosa, Chaenogobius gulosus, and Gymnogobius castaneus which accounted for 89.1% of total number of individuals collected. The number of individuals and biomass were higher from June to September when the water temperature was high. However, both the number of individuals and species showed the lowest from January and February. Highest species diversity index (H') was observed in April, 2012.

• Ocean and Polar Research
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• v.23 no.3
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• pp.311-313
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• 2001

Eighteen species of fish were identified by SCUBA diving observations around experimental artificial reefs at Tongyeong marine ranching area between November 1998 and November 1999. The highest species number of 14 was observed in September while the lowest number of 2 was observed in November. Fishes showed three typical behavioral patterns against the experimental artificial reef.

• Korean Journal of Ichthyology
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• v.21 no.sup1
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• pp.38-43
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• 2009