• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.374-384
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• 1999

Benthic marine algal flora and community structure of Yongho-dong area in Pusan, Korea were investigated seasonally in intertidal and subtidal zones by a quadrat method along 5 transect lines from July 1996 to April 1997. In this area, a total of 99 species including 3 blue-green, 13 green, 26 brown and 57 red algae was found. Among them, 33 taxa, together with dominant Ulva pertusa and Corallina pilulifera, occurred throughout the year. Enteromorpha spp. and Ulva spp. vertically distributed in upper and middle zone, while Simphyocladia latiuscula, Chondria crassicaulis, Corallina pilulifera and Sargassum sup. in lower zones. Biomass per unit area exhibited a wide range of variation, from 1,241 g/$m^2$(spring) to 1,648 g/$m^2$(summer) in fresh weight. Maximum and minimum species diversity were recorded in spring and autumn, respectively. Results of the UPGAM cluster analysis suggest that the examined 5 sites can be divided into two groups, sites exposed to open sea (transects 1, 2, 3) and comparatively sheltered sites (transects 4, 5) faced with the Pusan Harbor. The former group is represented by large brown algae, Sargassum and Hizikia, while Ulva pertusa and Lomentaria species are mainly found in the latter group. A calcareous alga, Corallina pilulifera occurred dominantly in both groups throughout the year. In conclusion, number of species in this area was remarkably reduced as compared to the previous data. This result may suggest probably more change of algal vegetation in future, considering the physical and chemical pollutions loaded in the coastal marine environment of this area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.295-302
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• 1999

To study the distribution of ichthyoplankton in the adjacent waters of Yousu, ichthyoplankton were sampled 4 times (September 1996, November 1996, February 1997 and May 1997). Four species of fish eggs and twenty-four species of fish larvae were identified. Among fish eggs, Engraulis japonicus eggs were the dominant species comprising $80.6\%$ of the total fish eggs collected, followed by Callionymidae spp. $1.6\%$, Konosirus punctatus and Maurolicus muelleri occupied below $1.0\%$ respectively, while $17.8\%$ were unidentified. Most larval fish species were found in September (17 species). In fish larvae, Callionymidae spp. was the dominant species occupying $25.7\%$ of total fish larvae collected and than followed by Gobiidae spp. $23.5\%$, Sillago japonica $17.2\%$ Engraulis japonicus $12.2\%$, Omobranchus elegans $9.9\%$ and the unidentified species were less than $2.0\%$. The larvae fish species collected in this study area were comprising the coastal sedentary species (Gobiidae, Callionymidae, Hexagrammos otakii and io on), and the warm water species (Auxis spp. and Coryphaena hipurus and Pomacentridae spp.) which were appearing by warm water current flowing near the costal area of Cheju Island.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.338-344
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• 1999

Floating debris was recorded from a training ship, $\sharp$1 Kwanaksan, of Pukyong National University with about 10 knots speed at July 15th and 20th of 1997. The sampled area is the middle of southern sea of Korea, divided into 44 unit segments on survey routes. Debris fabrication materials were categorized with 6 items using the following; man-made or natural wood items, paper and cardboard, nylon netting and rope, styrofoam, plastics, floating metal and glass containers. All identified items within a 100 $\pm$ 2 m wide band were recorded but ignored if beyond this boundary. The results of distribution and transport of floating debris in the area are as follows: 1. The quantities of debris during the survey were distributed from $1.6\~369.7\;items/km^2$. The most obvious trend is the widespread distribution of all debris. The highest densities of all debris were discovered in the coastal waters of Namhae and Yokji island, and of about 50 km off from the southward of Yokji and about 74 km off from the eastward of Komun island. Especially many of small styrofoams within $\phi$20 cm were observed in these segments. 2. Styrofoams and plastics were composed of $83.5\%$ among all debris, next woods items, $9.8\%$. 3. The quantities, distribution shapes and composition of debris were varied as the observed duration and the natures of each items. 4. These phenomena are concluded that firstly they depend on the river discharges included debris due to precipitation falls, secondly inflow or dumping debris are drifting to the off-shore by Kuroshio currents present at their adjacent sea, But on the basis of the observed data it is difficult that source position, quantities and inflow items of debris are identified, and also the transport processes is pursue. further more surveys are continuously being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps on all sites of the Coast of Korea and contributed to the stationary area, finding of sources, removal method of debris and resistants of marine productivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.435-442
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• 1995

The abalone shell (Haliotis) is one of the most important resources for the coastal fisheries and it is popular as an aquacultural species. Proper cultivating grounds for mid-term nursery of abalone spats are required before releasing them. It is difficult for us to find good enough aquacultural grounds to rear abalone spats to 20"30mm of shell length. Therefore, we need to study a practical and effective new type of aquacultural device for the nursing of abalone spats by using open sea areas. We can find this kind of studies from 'Marine aya No. 1' of Japan, Though they focused on the easy operation, safe working and low operating cost, it involves so much initial cost that it is difficult for us to justify such expenditure. However, with a modified small buoy system, this submersible facility needs only a horizontal frame to fulfill its essential function and the vortical part can be removed. The working boat equipped with a pump can operate this facility to keep it submerged or floated. This paper deals with the possibility of this submersible fishery facility for the mid term nursing of abalone spats in the open sea. A small version of this system to ensure low initial cost is suggested and wave and current forces were calculated for the estimation of the weight of the mooring anchor.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.4
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• pp.219-227
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• 1970

The shrimp fishery for Penaeus japonicus on the Koje-Do coast commences in May and continues to October. The best catches are made twice a year, namely June and September. Modal carapace length for the female is $51\~55\;mm$ in May, $51\~60\;mm$ in June occupying about 80 percent of the total catch. There is conspicuous mode in July and $46\~50\;mm$ in August. Modal carapace length for the male is $41\~45\;mm$ in May, $46\~50\;mm$ in June, $41\~45\;mm$ in July and August. The stock of p. japonicus can be divided into two groups, namely, spring and fall groups. Among samples of p. japonicus during the period from May through August the sex ratio consisted of about 33 percent females and 67 percent males, showing wide departure from a 1:1 ratio. The relationships between carapace length ($\iota$), body length (L) and body weight (W) are expressed by the following formulae : $$L=2.9418{\iota}+2.0166$$, $$W:1.449{\iota}^{2.2858}$$ (Mayssample) $$L=2.5551{\iota}+4.2986$$, $$W=1.528{\iota}^{2.2595}$$ (June sample) $$L=2.6738{\iota}+3.4037$$, $$W=1.341{\iota}^{2.3598}$$ (July sample) The relatlonship between carapace length ($\iota$) and ovary weight (W) is shown as follows: $W=2.695\times10^{-3}\iota^{4.2973}$ for May, June and July Samples.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.103-111
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• 1979

For the effective utilization of the coastal fish resources in Korea, an investigation on the optimum processing conditions and the quality of a textured fish protein concentrate similar to the texture of animal meat has been carried out with the fish meat of Alaska pollack and mackerel. A noodle shaped product was prepared with the fish meat paste after the adjustment of pH and salt content. The product was soaked in $96\%$ ethyl alcohol to produce textured fish protein concentrate and then dried. The processing conditions were estimated with the rehydration capacity of the textured fish protein concentrate(FFC). The quality of the final product was evaluated with chemical composition, sensory test and texture measurement. The optimum pH and salt content of the fish meat for the processing of meaty textured FPC were 7.5 and $1.0\%$ respectively. The most effective soaking conditions were as follows:soaking time, 40 min. ; temperature of alcohol, 5 to $20^{\circ}C$;amount of alcohol, 4 times the weight of tile fish meat paste, number of soaking in alcohol, 4 times. The alcohol remaining in meaty textured FPC could be removed effectively by forced air drying. The yield and the contents of protein and lipid in the meaty textured FPC from Alaska pollack were $19.9\%\;84.3\%\;and\;0.5\%$ and those from mackerel were $29.8\%,\;78.1\%\;and\;3.6\%$ respectively. The content of essential amino acid in the meaty textured FPC from Alaska pollack and mackerel was not inferior to that of beef, textured soybean protein and FAO pattern. Beef meat can be substituted with the meaty textured FPC up to $50\%$ in processing meat balls withoutanysignificantlossinthetaste, ordor and texture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.68-80
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• 1984

Garolim Bay is not only important fishing ground but also expected area for the tidal power plant. The construction and operation of tidal power plant will make change the ecosystem of this bay. Therefore, the actual fisheries stocks should be precisely understood for the effect estimation and overall utilization of the bay after the construction of the tidal power plant. During the study period from January through December in 1981, forty-six adult fishes species, 3 species of fish egg and 25 fishes larvae species have occurred in the bay. Considering the result on monthly distribution of eggs and larvae, the inner area of the bay seems to be important as nursing ground of larvae spawned at the outside bay in winter, e. g., Ammodytes personatus, and Enedrias sp. This inner bay is also major spawning ground for many species spawning in spring and summer, e. g., Gobiidae, Konosirus punctatus, Engraulis japonica, etc. Taking into consideration the annual mean production for three years($1978{\sim}1980$), there are two major fishing seasons. The one is in May-June for Enedrias larvae stock, and the another in October-November for big eyed herring stock. For the mariculture stocks, short necked clam, oyster and laver are important species. After construction of the tidal power plant, the migratory species, i. e., larvae of Enedrias and Ammodytes personatus, Mugil cephalus, Konosirus punctatus, etc. will be directly damaged by the interuption of migration route. On the otter hand, the change of physico-chemical factors of seawater will also affect the ecosystem of the bay. Consequently, for the overall utilization of the bay after construction, the actual ecosystem including the fisheries stocks, must bs precisely revealed, and the mechanical designs, e. g., sluice position and its demension, should be also considered with these biological characters of the bay.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.243-252
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• 1985

The mechanism of reproductive cycle of longchin goby Chasmichthys dolichognathus was investigated for the annual variations of gonadosomatic index(GSI), histological changes of gonad, reproductive cycle, and initiating and terminating factors of the breeding season. The experimental fish were captured in the tide pool of Tongbaeksom, Pusan, Korea from February 1983 to September 1984. Experimental fish for the study of initiating and terminating factors of the breeding season were maintained in filtered recirculating aquariums and exposed to various temperature and photoperiod regimes. The ovary is a pair of sac-shaped organ, and the testicular structure is tubular and it is connected to the seminal vesicle which is located at the posterior end of the testis. GSI began to increase from February when the water temperature began to increase and reached peak in April. It began to decrease from August, the top water temperature season, and maintained relatively low values until January. The annual reproductive cycle includes successive six developmental stages : early growing from December to February, late growing from January to March, early mature from February to May, late mature and ripe from March to August, spawning from April to July, degeneration and resting stage from May to December. An experimental study based on the reproductive cycle of this species indicated that rising temperature under long photoperiod during spring stimulated gonadal maturation, whereas terminating factor of the breeding season with recrudescence of the gonads was demonstrated as high water temperature during summer regardless of photoperiod.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.892-900
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• 2013

In 2011, the system for conserving and managing cetacean resources in Korea changed. The status of the cetacean bycatch was analyzed using a distribution certificate that was issued by the coast guard. During 2011.2012, 12 species were bycatch in Korean waters: three species of baleen whale and nine species of dolphin. The finless porpoise (Neophocaena phocaenoides) was the dominant species, followed by the common dolphin (Delphinus delphis), harbor porpoise (Phocoena phocoena), and Pacific white-sided dolphin (Lagenorhynchus obliquidens). Among the baleen whales, the common minke whale (Balaenoptera bonaerensis) was first and Bryde's (Balaenoptera edeni) and humpback (Megaptera novaeangliae) whales appeared in the Korea Strait and East Sea, respectively. Among the dolphins, the finless porpoise ranked first in the Yellow Sea. The common dolphin, Pacific white-sided dolphin, and harbor porpoise were more frequent in the East Sea than in other waters. The cetacean bycatch was caused mainly by pots, set nets, gill nets, and stow nets. Among the three species of baleen whale, the common minke whale was caught by pots and set nets, and comprised over 68.9% of the total bycatch in 2011 and 56.2% in 2012. Comparing the bycatch caused by fishing gears by area in 2011 and 2012, 97.9% and 99.6%, respectively, of the finless porpoise bycatch in the Yellow Sea was by stow nets. In the Korea Strait, trawl bycatch comprised 67.3% in 2011 and 73.0% in 2012, followed by gill nets, set nets, and pots targeting finless porpoise and common minke whales. In the East Sea, gill nets were responsible for 46.7% in 2011 and 61.2% in 2012, followed by set nets and pots.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.843-850
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• 2013

The feeding habits of Lycodes tanakae Eelpout were studied with 722 specimens collected from March 2011 to December 2012 in the coastal waters of the middle East Sea. The main prey of L. tanakae were fish, molluscs and arthropods. Nevertheless annelida, echinodermata and others were found in small amounts in the stomach contents. The L. tanakae stomach was empty of contents in 50.9% of specimens. While smaller size specimens of L. tanakae (less than 40 cm) fed mainly on euphausiids and amphipods, the larger specimens (more than 40 cm) fed on the fish Allolepis hollandi and Icelus cataphractus, and the molluscs Berryteuthis magister and Watasenia scintillans. The main prey items of L. tanakae varied seasonally. The fish Lycodes nakamurai was the dominat prey from November to January during its spawning season. Euphausiids and amphipods of the arthropods were the dominant prey from February to April. The molluscs Berryteuthis magister and Watasenia scintillans were the dominant prey from May to September. The diversity index (H') of diets showed variations by length class and month; the highest values were 2.61 in the length class of 51-55 cm, and the monthly highest were 2.68 in September with 23 species and 2.65 in November with 18 species. The highest dominance index (D') of diets was 0.57 in the length class of 31-35 cm, and the monthly highest was 0.71 in February. Cluster analysis divided prey groups into four groups by length class and three groups by monthly prey items. The gonad index gradually increased during the process of maturation while, contrary, stomach content index decreased during this period.