• 한국수산과학회지
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• 제47권1호
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• pp.79-83
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• 2014

Thirty five juveniles belonging to the genus Collichthys were collected using a bag net at Gang-wha-do, in the eastern Yellow Sea, between July and September, 2012, and identified using combined genetic and morphological methods. We sequenced 316 base pairs of mitochondrial DNA cytochrome c oxidase subunit I of 35 individuals, of which 22 individuals were identified as Collichthys niveatus (12.9-47.6 mm in SL) and 13 as Collichthys lucidus (13.4-40.3 mm SL). Morphologically, the number of occipital crests, an important taxonomic character during the adult stage, could not distinguish the two species during the juvenile stage, but the shape of the first anal fin spine clearly distinguished the two species even among juveniles.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.220-225
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• 2007

The movements of skipjack schools during purse seine operations were observed by scanning sonar in the Southwest Pacific Ocean in April 2004. Swimming speed and directional changes were analyzed in relation to heading of the purse seine during shooting, speed of the purse seiner and distance to the net. Escaped schools turned clockwise (relative to the heading of the purse seiner during shooting) significantly more frequently than captured schools, who primarily turned counter-clockwise. The swimming speed of a fish school, whether it was caught or escaped, was somewhat related to the ship's speed, but swimming speed did not differ between captured and escaped schools. The behavior of skipjack schools during purse seining consists of very complex movements with changes in swimming speed and direction in relation to the nets or purse seiner. Therefore, these responses of skipjack schools to purse seining can be useful for modeling the capture process of purse seining in relation to fishing conditions.

• Fisheries and Aquatic Sciences
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• 제20권2호
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• pp.2.1-2.5
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• 2017

This is the first report of Fowlerichthys scriptissimus (Lophiiformes, Antennariidae) from Korea. A single specimen (291.0 mm SL) was collected off the coast of Jejudo Island by gill net on 28 March 2012 and identified with morphological and molecular approaches. The specimen is characterized by having all five pelvic fin rays bifurcate and possessing 20 vertebrae, 13 pectoral-fin rays, and a basidorsal ocellus on the side of the body. This species is distinguishable from other Korean taxa by the number of pectoral fin rays, the bifurcate form of the pelvic rays, and the vertebral count. We add this species to the Korean fish fauna and suggest new Korean names, "Byeol-ssin-beng-i-sok" and "Byeol-ssin-beng-i" for the genus and species, respectively.

• Fisheries and Aquatic Sciences
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• 제19권10호
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• pp.43.1-43.5
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• 2016

Three specimens of Lutjanus ophuysenii (217.8-226.7 mm in standard length) were collected by a gill net at Korea between August 2015 and July 2016. This species has not previously been recorded from Korea. L. ophuysenii is very similar to Lutjanus vitta. But several morphological characteristics distinguish the two species, including the number of lateral line scales (46-49 scales in L. ophuysenii; 49-52 scales in L. vitta), a black spot in the middle part of the longitudinal stripe (present in L. ophuysenii; absent in L. vitta), and the absence of a scale on posterior end of the preopercle in L. ophuysenii (present in L. vitta). The Korean name proposed for L. ophuysenii is "Jeom-jul-tung-dom."

• 한국수산과학회지
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• 제28권3호
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• pp.309-315
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• 1995

This paper describes a monitoring system for fish farm formation effect based on personal computer by using an image processing technique. This method is based on image processing technique incorporating concept of window and threshold processing to track the target object and to distinguish it from background. The image processing program runs in the veal time so that all program modules are able to process multi-task. The effectiveness is evaluated through the comparative study on the motion of lantern net for the scallop culturing by wave action in an experimental wave tank.

• 한국수산과학회지
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• 제41권1호
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• pp.54-60
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• 2008

High- and multi-frequency acoustic systems can measure a zooplankton patch successively and estimate the spatial distribution and abundance of zooplankton according to size using a multi-frequency inversion (MFI) method. This study measured zooplankton distribution to a depth of 150m using a multi-frequency acoustic system (TAPS-6), installed on a CTD system with a fluorometer and analyzed it using the MFI method. Simultaneously, zooplankton samples were collected by north pacific standard (NORPAC) net to confirm the species composition. The results showed that the combined method is valuable for estimating the zooplankton profile in detail and investigating the relationship between the zooplankton and phytoplankton profiles.

• Fisheries and Aquatic Sciences
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• 제13권4호
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• pp.315-319
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• 2010

A single specimen of Carangoides hedlandensis was collected from a set net installed at 25 m depth near Sangju Beach, Namhae, Gyeoksangnamdo, Korea. The morphology of the species was similar to that of C. armatus. Carangoides hedlandensis and C. armatus can be clearly distinguished by the number of gillrakers on the first arch: C. hedlandensis has 20-28 gillrakers whereas C. armatus has 30-39. Unlike other species, interorbital region of the head in C. hedlandensis is bumped. We suggest that C. hedlandensis should be added to lists of Korean fish fauna, and propose a Korean name, "Hokjeon-gaeng-i" for this species.

• Fisheries and Aquatic Sciences
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• 제13권3호
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• pp.254-256
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• 2010

Length-weight relationships were estimated for 19 fish species in sargassum beds of Gamak Bay: Aulichthys japonicus, Pseudoblennius cottoides, Pseudoblennius percoides, Ditrema temmincki, Acanthogobius lactipes, Chaenogobius heptacanthus, Cryptocentrus filifer, Pterogobius elapoides, Pterogobius zonoleucus, Hyporhamphus sajori, Hexagrammos agrammus, Rudarius ercodes, Lateolabrax japonicus, Pholis crassispina, Pholis nebulosa, Scomber japonicus, Sebastes inermis, Ernogrammus hexagrammus, and Takifugu niphobles. Samples were caught by surrounding net at depths of <7 m between November 2007 and June 2008. The most abundant families were Gobiidae (26.3%), Cottidae (10.5%), and Pholididae (10.5%). Estimates for parameter b of the length-weight relationship (W=$aL^b$) ranged between 2.491 and 3.354.

• 대한수의학회지
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• 제58권1호
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• pp.39-43
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• 2018

The efficacy of using a bacteriophage (phage) to control Flavobacterium psychrophilum (F. psychrophilum) infection of ayu (Plecoglossus altivelis altivelis) was evaluated in this study. Intramuscular challenge failed to induce sufficient infection levels; therefore, a newly designed net-scratch challenge method was also used to induce bacterial infection. Administration of phage PFpW-3 in F. psychrophilum-infected ayu showed notable protective effects, increased survival rates and mean times to death. Additionally, the fate of inoculated bacteria and phage in ayu were investigated. Our results suggest that the phage PFpW-3 could be considered an alternative biocontrol agent against F. psychrophilum infections in ayu culture.

• 한국수산과학회지
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• 제51권5호
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• pp.595-599
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• 2018

One specimen (181.0 cm; TL, total length) of Echinorhinus cookei was collected from Busan, Korea in 2014 using gill net. Echinorhinus cookei was characterized by having no anal fin, no spine at dorsal fin and numerous small dermal denticles at the placoid scale. This species is very similar to the congeneric species, E. brucus, but differed in the shape of placoid scale (star in E. cookei vs. round in E. brucus) and distribution of placoid scale (separated in E. cookei vs. slightly overlapped in E. brucus). We adopted the Korean name, Ga-si-bi-neul-sang-eo, for E. cookei, after Kim and Ryu (2017).