• 수산해양기술연구
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• 제55권3호
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• pp.198-205
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• 2019

The small yellow croaker (Larimichthys polyactis) is one of the representative high-class fish species in Korea. The catch of small yellow croaker in adjacent water fisheries has been continuously decreasing from 59,226 tons in 2011 to 19,271 tons in 2016. The small yellow croaker is caught by gillnet, stow net and bottom trawl, among which about 55~65% is caught by gillnet. For the sustainable use of small yellow croaker, the fishing power of small yellow croaker drift gillnet is very important. Therefore, the change of fishing power index were analyzed to identify the development of the vessel and gear technology that may have improved the fishing efficiency of the small yellow croaker drift gillnet fishery from 1960s to 2010s. Gross tonnage and horse power per fishing vessel was increased annually. The mesh size was 75.0 mm in the 1960s, but reduced to 60.6 mm in the 1980s and to 51.0 mm in the 2000s. In the 1960s, it was hauled out by manpower. However, the net hauler were modernized and supply rate was also increased since 1970. Due to the mechanization of the net hauler, the number (length) of used net gradually increased from 1.5 km in the 1960s to 7.5 km in the mid-1980s and to 15 km in 2010. Colour fish finders and positioning system were introduced and utilized from the mid-1980s. Surveys on the supply and upgrading of fishing equipment utilized visiting research. Therefore, the relative fishing power index in the small yellow croaker drift gillnet fishery increased from 1.0 in 1980 to 0.8 in 1970, to 1.1 in 1990, to 1.6 in 2000 and to 1.9 in 2010. The results are expected to contribute to reasonable fisheries stock management of the small yellow croaker drift gillnet fishery.

• 수산해양기술연구
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• 제54권3호
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• pp.224-230
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• 2018

Squid is one of the important fisheries resources in Korea. Therefore, squid has been designated and managed as a target species of total allowable catch (TAC) since 2007, but the catch amount is gradually decreasing. The analysis was conducted to identify the change of relative fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the offshore squid jigging fishery from 1960s to 2010s. Gross tonnage per fishing vessel increased with the increase in size until 1990, but then gradually decreased to 41.0 tons in 2000 and 37.1 tons in 2010. The illuminating power (energy consumption) by fishing lamps increased to 180 kW in 2005 and stabilized to 120 kW in 2015. Jigging machine started to be supplied to fishing vessels from the early 1970s, and fish finders began to be supplied in the early 1980s and gradually increased. Therefore, the relative fishing power index in the offshore squid jigging fishery increased from 1.0 in 1980 to 1.1 in 1990, to 3.5 in 2000 and to 2.5 in 2010, but the increment rate slowed down gradually. The results are expected to contribute to reasonable fisheries stock management.

• Ocean and Polar Research
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• 제23권4호
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• pp.425-431
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• 2001

From an ecological point of view, the western part of the Atlantic sector is one of the most productive areas in the Southern Ocean. Antarctic krill (Euphausia superba) and krill-dependent predators such as fish, seals, and birds are abundant there, and most krill fisheries have operated in this area since 1970s. The hottest issues for the proper management of krill resources nowadays are to determine total biomass in this area, and to identify environmental forces controlling stock fluctuation. This paper reviews and collates information on ongoing oceanographic activities in the Antarctic Peninsula region concerning these issues. To delineate the status and function of Antarctic krill population in Antarctic marine ecosystems, multinational researches along the Antarctic Peninsula area have been developing recently. Four member states of CCAMLR (Japan, Russia, UK, and USA) had conducted acoustic surveys in January-February 2000 (socalled CCAMLR-2000 survey), and krill standing stock at 120 kHz was estimated to be 44.29 million metric tonnes in the western Atlantic sector of the Southern Ocean. On the other hand, the Southern Ocean GLOBEC (SO-GLOBEC) Programme has prepared a serial winter survey to examine the factors that govern krill survivorship and distribution in relation to shelf circulation processes. Ship-based surveys using ice-breakers are being conducted by three nations (Germany, UK, and USA) around the Marguerite Bay during the austral fall and winter 2001 and 2002. In addition to these two large-scale surveys, some CCAMLR members have carried out joint oceanographic surveys near the South Shetland Islands to detect ecosystem changes since 1994. Especially from December 1999 to February 2000, in conjunction with CCAMLR-2000 survey, four nations (Japan, Korea, Peru, and USA) conducted acoustic surveys to produce time-series information on krill distribution and biomass near the South Shetland areas. Though the aims of each program and the approach to solve the scientific questions were different each other, the results from each program fill the gaps between programs. Further cooperation and exchange in these activities could be beneficial to each program.

• 동아시아식생활학회지
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• 제12권3호
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• pp.197-209
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• 2002

This study was performed to investigate and analyze the level of recognition, preferences and quality factors of sauces. A total of 1,340 subjects, 660 males and 680 females in the Daegu and Kyeongbuk areas participated in a questionnaire for this study. The results were summarized as follows: Among the respondents, 41.1% answered that they learned about the sauces from a western style restaurant. 73.4% of the respondents suggested that the taste and the quality of sauces had an influence on their preferences of western dishes. 51.2% of the respondents recognized that sauces are mainly used when baking and broiling; it was widely known that demiglace sauce is used on steaks. The preferred colors of sauces from most popular to least popular were brown, blond, white, yellow and red. The overall favorite stock material of demiglace sauce was beef bone. Foods that were preferred to be served with sauces were found to be beef, pea seafood, fish, shellfish, poultry and cereals from most preferred to least preferred. The favorite sauces were brown stock sauce, tomato sauce, liquor sauce, and cream sauce from most preferred to least preferred. The oil and butter sauces were preferred the least. Using a scale of 1 to 5 with 5 being the highest, the respondents rated the way sauces were cooked as the most important the quality-determining factor, with a mean value of 4.31. The raw ingredient as the most important factor was rated 4.45. Among sensory factors, the respondents agreed taste was that the most important characteristic, with a mean value of 4.65. 36.0% evaluated the overall quality of sauces as good and 47.0% as ordinary when served with western dishes. 44.1% of the respondents stated that the taste is was the topmost characteristic that needed to be improved, and that flavor and color were next in order.

• Fisheries and Aquatic Sciences
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• 제23권6호
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• pp.16.1-16.10
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• 2020

This study was conducted in Lake Hayq between January and December 2018. The objectives of this study were to determine the growth, condition, sex ratio, fecundity, length at first sexual maturity (L₅₀), and spawning seasons of common carp (Cyprinus carpio). Monthly fish samples of C. carpio were collected using gillnets of stretched mesh sizes of 4, 6, 7, 8, 10, and 13 cm and beach seines of mesh size of 6 cm. Immediately after the fish were captured, total length (TL) and total weight (TW) for each individual were measured in centimeters and grams, respectively, and their relationship was determined using power function. Length at first maturity (L₅₀) was determined for both males and females using the logistic regression model. The spawning season was determined from the frequency of mature gonads and variation of gonadosomatic index (GSI) values of both males and females. Fecundity was analyzed from 67 mature female specimens. The length and weight relationship of C. carpio was TW = 0.015TL^2.93 for females and TW = 0.018TL^2.87 for males that indicate negative allometric growth in both cases. The mean Fulton condition factor (C_F) was 1.23 ± 0.013 for females and 1.21 ± 0.011 for males. The value of C_F in both cases was > 1 that shows both sexes are in good condition. Among the total 1055 C. carpio collected from Lake Hayq, 459 (43.5%) were females and 596 (56.5%) were males. The chi-square test showed that there was a significant deviation between male and female numbers from 1:1 ratio (χ²= 22, df = 11, P > 0.05) within sampling months. The length at first sexual maturity (L₅₀) for females and males were 21.5 and 17.5 cm, respectively. Males mature at smaller sizes than females. The spawning season of C. carpio was extended from February to April, and the peak spawning season for both sexes was in April. The average absolute fecundity was 28,100 ± 17,462. C. carpio is currently the commercially important fish while Nile tilapia fishery has declined in Lake Hayq. Therefore, this baseline data on growth, condition, and reproductive biology of common carp will be essential to understand the status of the population of carp and design appropriate management systems for the fish stock of Lake Hayq, Ethiopia, and adjacent countries.

• 한국수산과학회지
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• 제37권6호
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• pp.478-484
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• 2004

On 11 June 1991, eggs from the brood stock of small yellow croaker (Larimichthys polyactis) were artificially fertilized using the standard dry method and were hatched. Each of the fertilized eggs (1.1-1.2 mm in diameter) had an oil globule and was transparent and buoyant. The fertilized eggs hatched in a range of water temperatures $(17.5-20.3^{\circ}C)$ 44 hrs after fertilization. The total lengths of the newly hatched larvae were 3.1-3.3 mm, and these hatchlings had 31 myotomes (10+21). Melanophores and yellow-brown chromatophores were concentrated on the head, at the ventral part of the yolk, and in the middle of the tail. Four days after hatching, the larvae completely absorbed the yolk and became flexions of 5.1-5.5 mm in total length. Fifteen days after hatching, one spine (the anterior tip of the maxillary) appeared in the upper jaw and three spines developed at the upper parts of the eyes and on the posterior part of the head. At this stage, the larvae were approximately 8.3 mm long. Thirty-nine days after hatching, juveniles (1.9-3.4 mm in total length) had a pointed tail fin. By 66 days after hatching, the juvenile fish (about 4.0-6.5 mm in total length) were similar to adult fish in body shape. The larvae of L. polyactis could be distinguished from those of L. croacea by two distinct characteristics: the large number of vertebrae (28-29), and a relatively small bony ridge on the occipital region of the head.

• 대한지역사회영양학회지
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• 제20권1호
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• pp.11-20
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• 2015

Objectives: The purpose of this study was to examine mothers' eating behavior and salty taste and its relationship to their preschool children's eating behaviors. Methods: This survey was conducted by self-report after getting permission from sixty one mothers who had preschool children. The questionnaire was focused on mothers' salty test and salt-related eating behavior of both mothers and their preschool children. Results: Comparison of eating behavior score between mother and their preschoolers showed that mothers' score was lower than their preschoolers' one. Salty foods with high preference and intake frequency by mothers and preschoolers were 'salted dry fish, stock fish' and 'soup, stew, noodle soup'. In addition, there were strong positive correlations between preference and intake frequency on most of the salty food items. Intake of Ramen soup was significantly different (p < 0.001) between the two groups. Preschoolers ate less ramen soup compared to their mothers. Conclusions: Overall results showed that preschoolers' dietary behavior was better than the mothers' one. However, preschoolers' dietary behavior was significantly influenced by their mothers. Therefore, mothers should have an appropriate eating behavior in order to have a positive influence on their children's eating habits. In addition, the results suggested that proper nutrition education is needed for mothers of preschool children.

• 한국양식학회지
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• 제20권4호
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• pp.219-225
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• 2007

본 연구는 양식산 뱀장어 Anguilla japonica의 인위적인 성성숙 처리시기와 번식률과의 상호 관련성을 확인하기 위해 5월(봄)부터 익년 1월(겨울)까지 각 계절별로 수행되었다. 실험어의 인공 성성숙 유도를 위해 암컷($400{\sim}600\;g$) 뱀장어에 salmon pituitary extraction (SPE, 20 mg/fish/week)를 매주 복강에 주사하여 인위적인 성성숙을 유도하였다. 호르몬 처리 $8{\sim}13$주 이후 대부분의 개체들은 난황형성이 완료되었고, $17{\alpha}$, $20{\beta}-dihydroxyprogesteron$ (DHP, $2\;{\mu}g/g$ body weight)를 주사하여 배란을 유도하였다. 수컷 뱀장어($200{\sim}350\;g$)는 human chronic gonadotropin (HCG, 1 IU/g body weight/week)을 매주 복강에 주사하여 정자형성 및 배정을 유도하였고, 이후 상기의 개체들에 대해 자연산란에 의한 수정 및 인공수정을 병행하였다. 배란율, 부상률, 수정률 및 부화율을 포함한 계절별 번식률에 있어서 봄과 여름($5{\sim}7$월)에 인공성성숙을 유도한 실험구가 다른 계절에 비해 높았다. 산란수와 부화 유생수 및 부화유생의 생존일수는 번식률과 유사한 경향을 나타내었다. 본 연구결과, 양식산 뱀장어에 있어서 호르몬 처리에 의한 인공성성숙유도의 시기는 자연계에서 주산란시기인 봄과 여름철이 적합함을 나타내고 있다. 따라서, 양식산 뱀장어의 적절한 인공성성숙시기는 배란율, 부상률, 수정률 및 부화율을 포함한 번식률에 의해 결정할 수 있다.

• 한국수산과학회지
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• 제22권5호
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• pp.306-316
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• 1989

우리나라 근해에서 어획되는 병어류의 어획물에 혼재된 "병어"와 "덕대"의 혼획비를 조사하고, 그중에서 양적으로 월등히 많은 것으로 확인된 덕대를 대상으로 실측 조사된 체급별 체장조성과 어체조사자료를 기초로 하여 자원해석을 실시하고 자원관리방안을 검토하였다. 병어류의 어획물중에서 덕대의 혼획비율은 중양비로써 $60\~70\%$를 차지하는 것으로 밝혀졌으며, 어획물의 체장조성은 FL 15 cm를 중심으로 한 단일 mode로 구성되고 체장조성의 연변동은 거의 없었으며, 연령조성은 1세어가 $41\~46\%$를 차지하며 다음으로 많은 조성비를 차지하는 것은 0세어로 나타났다. 현재의 자원특성치는 다음과 같이 추정되었다. 자연사망계수(M) : 0.6 어획사망계수(F) : 0.924($1986\~1988$년 값의 평균) 어장가입년령($t_r$) : 0.19 어획개시년령($t_c$) : 0.49 0세어의 어장가입률(Q) : 0.29 가입당어획이론에 의하여 이루어진 자원진단결과 어획개시연령과 어획사망의 두 가지 기준에서 볼 때 덕대의 현재 자원상태는 적정수준이하에 있으며, 어획강도의 조절에 의한 어획량증가효과는 거의 없으므로 최선의 관리방법은 어획강도의 조절보다 어획개시년령을 현재의 0.49로 부터 1.5세 부근까지 높이는 것으로 판단되었다.

• 한국해양공학회지
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• 제17권2호
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• pp.8-13
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• 2003

Soil, ground water, and sea bed are exposed to a continuous accumulation of polluted materials, causing serious environmental damage. It has been reported that such pollution causes a massive mortality of fish stock in rivers due to the resuspension of toxic chemicals, occurring during strong wind conditions. Therefore, it becomes apparent that there is an immediate demand for the restoration treatment of polluted river bed (or sea bed) sediment layers. Pollution levels of major rivers and ports, such as Paldang, Kyungan rivers, and Masan port, are becoming of great public concern, and are posing a serious environmental threat. In particular, the pollution of the Shi-hwa river has become a nation wide issue for the last few years. In spite of such public concern, the pollution levels of such rivers or ports are worsening everyday. In this study, an environmentally sound engineering package is introduced that helps to restore the polluted river bed or sea bed sediments. This engineering package consists of a suction facility, followed by a series of mechanical, chemical, and biological treatment units. The suction facility is designed to minimize secondary pollution that occurs from the resuspension of toxic materials during suction. The sea bed cleaning engineering package is designed to be installed on the top of a floating barge. Such a combination of environmental plant and shipbuilding technology provides a cost-effective solution, minimizing the transportation between suction and treatment facilities.