• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.248-253
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• 2007

We studied the maturation and spawning of female Spanish mackerel (Scomberomorus niphonius) based on 445 specimens collected monthly from January to December 2004 in the coastal waters off Busan. The fork length (FL) of S. niphonius ranged from 26.1 to 105.4 cm, the gonadosomatic index (GSI) of the females was highest in May 2004, and the spawning season take place from April to July. A significant difference was detected in the sex ratio between females and males ($X^2$ test, p<0.01). The percentage of sexually mature females exceeded 50% in the 50-60 cm (FL) size group and reached 100% in the over 70 cm (FL) size group. Fecundity (F) varied between 201,156 and 836,426 egg per female. The relationship between F and FL of the fish was expressed as $F=5.8756FL^{3.8465}$. The relationship F and body weight (BW) was expressed as F=581.421 n (BW)-4108.5. The first spawning length was 41.8 cm (FL.)

• 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 Ichthyology
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• v.20 no.2
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• pp.117-122
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• 2008

The feeding habits of Scorpaena neglecta were studied based on an examination of the stomach contents of 478 specimens collected between January and December 2006 in the Coastal Waters off Busan. The specimens ranged from 9.0 to 23.5 cm in Standard length (SL). S. neglecta is a piscivore and consumes mainly teleosts such as Acropoma japonicum, Coelorinchus multispinulosus, Chaeturichthys stigmatias. Its diet also includes crabs, shrimps, cephalopod and stomatopod. Smaller individuals (<16 cm SL) consume mainly crabs and shrimps. The proportion of these prey items (crabs and shrimps) decreases with increasing fish size, and this decrease parallels the increased consumption of fish. The mean prey size sharply increases between 12 and 20 cm SL of S. neglecta size.

• Korean Journal of Ichthyology
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• v.19 no.1
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• pp.51-56
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• 2007

The feeding habits of bluefin searobin (Chelidonichthys spinosus) were studied based on the examination of stomach contents of 646 specimens collected from January 2005 to December 2005 in the coastal waters off Busan, Korea. The size of C. spinosus ranged from 14.0 to 38.9 cm in standard length (SL). C. spinosus mainly consumed shrimps such as Solenocera melantho, Leptochela sydniesis and Trachysalambria curvirostris. Its diet also included crabs and fishes. Smaller individuals (15~25 cm SL) consumed small shrimps such as L. sydniesis, crabs and fishes. The portion of these prey items decreased with increasing fish size, and this decrease was paralleled with increased consumption of lager shrimps such as S. melantho and Trachysalambria curvirostris. The prey size increased with the increase of fish size.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.370-374
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• 2015

Pacific herring Clupea pallasii eggs were attached to the gill net in Korean coastal waters off Busan. To conservation and management the eggs attached to the gill net, we followed the natural hatching in coastal waters from five days after fertilization to the hatching finished, where the temperature was $9^{\circ}C$. The diameter of fertilized eggs was 1.24-1.55 mm (n= 50), and had a segmented pale yellow yolk, no oil globule. Natural hatching had started by 10 days after fertilization. Mass hatching occurred around 11-12 days after fertilization, most of eggs separated from the gill net. Therefore, when the Pacific herring eggs attached in gill net, should be natural hatching-induced in coastal waters during 12-14 days.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.4
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• pp.429-436
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• 2017

The seasonal and interannual variations in fish assemblages in the coastal waters off Gijang were examined with an otter trawl from 2015 to 2016. A total of 59 fish species was collected during the study period. The dominant species were Caelorinchus multispinulosus, Clupea pallasii pallasii and Chelidonichthys spinosus. Seasonal changes in fish assemblages appeared to be distinct in the study area. The fish assemblages in summer and autumn were clearly distinguishable from those in other seasons, and the largest numbers of species and individuals were captured in winter and summer, respectively. Because fish assemblages are closely related to changes in water temperature, long-term changes in water temperature can have a significant impact on the productivity of offshore fisheries by changing fish species composition, habitat migration, and growth rate of fish.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.216-222
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• 2006

Feeding habits of Pagrus major collected in the coastal waters off Busan from January to December 2004 were studied. P. major ranged form 8.5 to 44.6 cm in standard length. P. major was a carnivore which consumed mainly hermit crabs, amphipods, crabs, shrimps, polychaetes, echinoderms, and fishes. Its diets included small quantities of gastropods, bivalves, stomatopods, cephalopods, cnidarians, and isopods. It showed ontogenetic changes in feeding habits. Small individuals (8~15 cm SL) preyed mainly on shrimps. However, individuals from 15 cm to 25 cm SL preyed mainly on hermit crabs and polychaetes. Individuals over 25 cm SL preyed mainly on fishes and echinoderms.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.59-75
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• 2012

The species composition of plankton is essential to understand the material and energy cycling within marine ecosystem. It also provides the useful information for understanding the properties of marine environments due to its sensitivity to the physicochemical characteristics and variability of water masses. In this study we adopted metagenomics to evaluate eukaryotic plankton species diversity from coastal waters off Busan. Characteristics of water masses at sampling sites is expected to be very complex due to the mixing of various water masses; Nakdong River runoff, Changjiang diluted water (CDW), South Sea coastal water, and Tsushima warm current. 18S rDNA clone libraries were constructed from surface waters at the three sites off Busan. Clone libraries revealed 94 unique phylotypes from 370 clones; Dinophyceae(42 phylotypes), Ciliophora(15 phylotypes), Bacillariophyta(7 phylotypes), Chlorophyta(2 phylotypes), Haptophyceae(1 phylotype), Metazoa(Arthropoda( 17 phylotypes), Chaetognatha(1 phylotypes), Cnidaria(2 phylotypes), Chordata(1 phylotype)), Rhizaria (Acantharea(2 phylotypes), Polycystinea(1 phylotype)), Telonemida(1 phylotype), Fungi(2 phylotypes). The difference in species diversity at the closely located three sites off Busan may be attributed to the various physicochemical properties of water masses at these sites by the mixture of water masses of various origins. Metagenomic study of species composition may provide useful information for understanding marine ecosystem of coastal waters with various physicochemical properties in the near feature.

• Ocean and Polar Research
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• v.44 no.3
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• pp.261-267
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• 2022

We derived a length-weight relationship for Calanus sinicus off Busan, Korea in spring to estimate the biomass of the C. sinicus population around Korean waters, and compared it with the previously derived equations. The developmental stages and prosome length of C. sinicus used in the relationship ranged from 1,376-1,540 ㎛ for copepodite 4 (CIV), 1,753-1,971 ㎛ for copepodite 5 (CV), and 2,160-2,283 ㎛ for adults (CVI). Dry weight and carbon content were measured from a total of 26 replicates. Length-weight relationships derived in the present study are as follows: log C = 3.342 log PL - 9.449, log DW = 3.394 log PL -9.219, where C is carbon content (㎍), DW is dry weight (㎍), and PL is prosome length (㎛). When comparing the present regression equation of length-weight for C. sinicus with the previous one, our regression equation showed an average carbon estimate to a given range of mean prosome length. The length-weight relationship of C. sinicus in the present study can be used to better estimate the biomass of the C. sinicus population in the coastal waters of Korea.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.297-300
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• 2015

This is the first report of Champsodon longipinnis (Champsodontidae) collected from Korea. The specimen (100.9 mm in standard length) was caught by a bottom trawl in the coastal waters off Busan, Korea. This species is characterized by the following morphological traits: body with small denticulate scales except abdomen around pelvic fin base; posterior end of maxilla extending beyond margin of eye; dark pigmentation on most of the first dorsal fin, upper half of the first to the fourth soft ray of the second dorsal fin, and partial upper lobe of caudal fin. We add C. longipinnis to the Korean fish fauna and suggest a new Korean name, "Jeom-ak-eo-chi," for the species.