• Ocean and Polar Research
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• 제35권4호
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• pp.323-349
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• 2013

The mud shrimp Upogebia major (Upogebiidae: Decapoda: Crustacea) is a common species on muddy and sandy mud tidal flats in the west coast of Korea. They reside in Y-shaped burrows that can extend up to more than 2 meters below the sediment surface. They feed on suspended detritus carried into their burrow by the beating of their pleopods and captured by their hairy first two pairs of thoracic legs. Mud shrimp burrows provide a habitat for a variety of small organisms such as crabs, shrimps, polychaetes, and mollusks. Ovigerous females are observed from December to May. Females deposit eggs only once per breeding season. They start hatching in March and the pelagic larvae of first zoea appear in March and April, followed by benthic settlement in May. Growth over the first year is rapid, and females deposit their first eggs in the third breeding season, 31 months after their settlement. Adult shrimps live for 4~5 years. Depth of the burrow increases with body length. The deep burrows provide refuge from predators and physical stress, allowing the shrimps to survive for a long time. The mud shrimps supply oxygen-rich water to their deep burrows, and exert a great influence on the structure and metabolism of the tidal flat benthic community. However, recently this type of mud shrimp has posed a serious threat to the Korean clam industry along the west coast of Korea. The extensive burrowing shrimp populations suddenly invaded the tidal flats from 2010 where the clams (Ruditapes philippinarum) are raised. As a consequence, clam production has decreased by about 10% over the past three years in some Korean clam beds. Therefore, the objective of this study is to review the biology of this mud shrimp in order to seek solutions to control the burrowing of these shrimps.

• 한국수산과학회지
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• 제38권4호
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• pp.232-238
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• 2005

This paper describes reproduction, population structure, growth and size at sexual maturity of a deep-water mud shrimp (Solenocera melantho) in the adjacent waters of Geomun Island, Korea. The shrimp was caught by a beam trawl from November 1998 to December 1999. Spawning period was estimated by gonadosomatic index to be from August to early November with a peak in October to early November. Female shrimps were $12\%$ matured at 16 mm in carapace length, $33\%$ matured at 18 mm and $75\%$ matured at 22 mm. The size at $50\%$ maturity for female was estimated to be 20.65 mm in carapace length. Breeding season was estimated to be from August to early November with a peak in October to early November. The size at $50\%$ inseminated was 19.81 mm CL. The fecundity was 87,500-405,200 and related exponentially to carapace length and total weight. This species survived between 25 and 26 months. The maximum carapace length of females and males were 48 mm and 34 mm respectively. Sex ratio was $51.3\%$, and the females were preponderant. Growth was estimated by modified von Bertalanffy growth function incorporating seasonal variation in growth in both years females (K=1.019/yr and $L_{\infty}$=51.731 mm CL) grew faster, reaching a larger size at a given age than males (K=1.848/yr, and $L_{\infty}$=27.499 mm CL). This is indicated by differences in growth performance indices $(\varphi')$ between females (3.291) and males (3.145).

• Ocean Science Journal
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• 제41권3호
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• pp.175-179
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• 2006

The Ieodo Ocean Research Station(IORS) is an integrated meteorological and oceanographic observation base which was constructed on the Ieodo underwater rock located at a distance of about 150 km to the south-west of the Mara-do, the southernmost island in Korea. The underwater ambient noise level observed at the IORS was similar to the results of the shallow water surrounding the Korean Peninsula (Choi et al. 2003) and was higher than that of deep ocean (Wenz 1962). The wind dependence of ambient noise was dominant at frequencies of a few kHz. The surface current dependence of ambient noise showed good correlation with the ambient noise in the frequency of 10 kHz. Especially, the shrimp sound was estimated through investigations of waveform and spectrum and its main acoustic energy was about 40 dB larger than ambient noise level at 5 kHz.

• Animal cells and systems
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• 제16권1호
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• pp.77-84
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• 2012

The objective of the study was to investigate if reproductive characteristics of $Pandalus$ $eous$ affect the depth distribution in the East Sea of Korea. $P.$ $eous$ was found at depths of 500-900 m in the East Sea of Korea, with the highest percentage occurrence (34%) at 500 m. A negative correlation was observed between the number of individuals and the depth. The overall sex ratio also turned out to be significantly correlated with depth. On average, the larger individuals (bigger than 26.37 cm), which included transitional, female, and ovigerous females, were mostly distributed at 700 m depth. The percentage of males increased by depth and ovigerous females were mainly distributed in the shallow water (300 m) during winter. Ovigerous females were not found at 900 m, which is the deepest depth range in this study. The percentage of transitional individuals was greatest at 500 m and decreased gradually with depth. All ovigerous female individuals were of the spent ovarian stage in winter. Female numbers in the ripe ovarian stage increased with depth and immature females rarely appeared. The gonadosomatic indices of the nonovigerous females and ovigerous females were highest at 700 m in depth. The mean egg size of $P.$ $eous$ was $0.83{\pm}0.11mm^3$ in the non-eyed stage and $0.93{\pm}0.17mm^3$ in the eyed stage.

• 한국식생활문화학회지
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• 제19권3호
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• pp.273-284
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• 2004

This study is on the changing pattern of fish-and-shellfish uses during the last two thirds of Chosun period on the premise that they are influenced by development of fishing technology. With a literary approach, this paper researches how fish-and-shellfish production and consumption pattern changed, especially in relation to technological development of fisheries. First, we examine into the changes of fishery production. And next, we analyze the kind and cooking method of fish-and-shellfish in [Eum-sik-di-mi-bang](1670) and [Gyu-hap-chong-seo](1815). The analysis of two books revealed that there were significant differences in fish-and-shellfish uses. Because the two books were written with a gap of 145 years and the development of fishing technology and remarkable changes of fishery production affected on the fish-and-shellfish uses. Due to primitive fishing tools and skills, fresh-water and reverse-river-fish and shellfish had been caught in substantial amount until the middle ages of Chosun period. As a result, the availability of seafood were limited extremely even in the upper classes. These situations are evidenced by the analysis of [Eum-sik-di-mi-bang]. Only 12 kinds of fish-and-shellfish are described in [Eum-sik-di-mi-bang]. Most of the sesfoods is mollusc which is easy to catch. As for the salt-water fish, dried cod and dried herring were mentioned. Mullet, the reverse-water-fish, is used most frequently. Only one kind of 'Hoe', which needs extreme freshness, is described. This means that the use of fresh fish-and-shellfish was very limited to some kinds which could be caught near the village. As the netting fishery began to be developed in the 18th century, the production of some salt-water fishes, such as anchovy, shrimp, yellow corvina, pollack, and herring, had increased remarkably to make marine resources more available. Small fish, such as anchovy and shrimp were preserved as 'Jeot-gal' and sold nationwide. Therefore, 'Jeot-gal' and seafood could be used in Kimchi around this time and had a deep influence on the change of Kimchi in taste and nutrition. In [Gyu-hap-chong-seo], 33 kinds of fish-and-shellfish are described. Including cod and herring, 17 kinds of sea water fish and mollusc are mentioned. Some of these are consumed in fresh state, neither as dried nor as salted. Because the merchants promoted the transport of seafoods to other regions according to the growth of commercial economy. As a result the diet of the people could be enriched by the various seafoods.

• 수산해양기술연구
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• 제47권4호
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• pp.300-315
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• 2011

The investigation for the catch and species composition in the deep sea of the East Sea was done to search marine organisms using some kinds of traps with small commercial fishing vessel near Goseong, Korea from 2008 to 2009. The experiments was carried out with some different traps at the depth of 200m, 400m, 700m and 1,000m. In 2008, the amount of catch with rectangular, cone and drum net traps was 91.4kg with twelve trips and the proportion of catch with rectangular and cone traps was high. Dominant species caught were Aniwan whelk (57%), snow crab (12%), hunchback sculpin (7%) and red snow crab (5%). The catch of Aniwan whelk was done well with rectangular and cone traps at the depth of 700-1,000m. Snow crab was mainly caught with rectangular and cone traps at the shallower depth of 200m, while red snow crab caught a lot with cone trap at the deeper depth of 700m. In 2009, the amount of catch with rectangular, cone and round traps was 92.4kg with nine trips. The proportion of catch with round trap was higher than that with cone trap. Dominant species caught were snow crab (67.1%), Aniwan whelk (14.8%) and northern shrimp (9.8%). Snow crab was caught well with round trap at the depth less than 400m.

• 한국해양바이오학회지
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• 제3권1호
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• pp.1-6
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• 2008

Angola has a coastline of about 1,650 km long. Two diverging current namely, the Angola current with its warm water from the north and the cold Benguella Current in the south create a strong up-welling with a high productive ecosystem for marine resources. The area from Lobito to the mouth of the Cunene River, also known as the Southern fishing zone is by far the most productive of Angola's fishing zones. In 1977, the total potential of its marine fisheries sector was estimated at more than 700,000 tonnes per annum. In 2003, the Total Allowable Catch (TAC) established for demersal species was 57,600 tonnes and 160,000 tonnes for pelagic species. The most important resources are various marine demersal and pelagic fish including pilchard and the Cape and Cunene horse Mackerel (Tranchurus capensis and T. trecae). Sardinellas (Sardinella aurita and S. maderensis) are fished in parallel with horse mackerel. The rest of the catches are mainly demersal spp. and some deep water crustaceans. The demersal sppecies consist of Hake (Merluccius polli and M. capensis) and the large eye dentex spp. Tunas are caught at certain times of the year whilst some marine shrimp are also harvested from the Angolan waters. Angola also has several high value freshwater fish species, exploited by about 255 fishers. Tilapia sp. is among the most important and abundant fresh water fish found in Angola. Other species include the catfish (Clarias gariepinus) and fresh water prawns (Macrobrachuin rosenbergii). Some aquaculture ponds have been established in the country side, but due to lack of investment, proper training and the impact of civil war have seriously limited developments in the sub sector.

• 한국수산과학회지
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• 제22권2호
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• pp.49-58
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• 1989

멸치를 보다 효율적으로 식량화하기 위한 일련의 연구로서 4가지 조건으로서 가공한 멸치스낵의 품질비교 및 저장안정성에 대하여 실험하였다. 마쇄한 멸치에 부원료를 첨가하고, 어취개선을 위하여 향신료를 첨가한 후 저장중 문제가 되는 지질산패를 방지하기 위하여 sodium erythorbate를 첨가한 다음, 소금튀김하여 제조한 제품이 가장 좋았다. 이런 조건하에서 제조된 스낵제품은 제조직후 수분함양이 $6.5\%$, 조단백질 $8.7\%$, 조지방 $28.1\%$, 탄수화물이 $51.6\%$, pH가 7.6이었으며, 저장중수분함양, 수분활성, pH, 휘발성염기질소 및 구성 아미노산의 변화는 거의 없었다. sodium erythorbate를 첨가함으로서 저장중 제품지질의 산패를 다소 억제시킬 수 있었다. 원료어의 주요구성지방산은 16:0, 22:6, 20:5 및 18:1 이었고, 제품의 경우는 18:1, 16:0 및 18:2였는데 이러한 차이는 튀김유인 팜유에 기인한다고 볼 수 있다. 저장중제품의 색조는 L값은 감소하였고 a값, b값 및 ${\Delta}E$ 값은 증가하였다. 무기질, 아미노산조성 및 관능검사결과로 미루어 보아 멸치스낵제품은 쓴맛과 튀김공정후에 다소의 지질을 제거한다면 시판스낵제품과 비교하여 품질면에서 손색이 없으면서 영양성분의 균형이 잡힌 우수한 스낵식품이라는 결론을 얻었다.