• Title/Summary/Keyword: By-catch

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A Study on Fishing Efficiency and By-Catch of Small Fish of Winged Stow Net Fishery (연안 낭장망어업의 어획성능과 소형어 혼획에 관한 연구)

  • Kim, Joo-Seong;Lee, Ju-Hee
    • Journal of Fisheries and Marine Sciences Education
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    • v.8 no.1
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    • pp.92-107
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    • 1996
  • Based on the act.ivity report for the coastal fisheries resources conducted from 1982 to 1989 by West, East Research Institute of Fisheries, some other reports from Korea Rural Economics Institute and etc., and the questionnaire results for the senses of fishermen, the fishing efficiency and conditions of by - catch of small fish in winged stow net were analized, and then some ways to prevent from by - catch of small fishes were suggested in this paper. The nationwide conditions of Permission and Disposal in winged stow net fishery arc that number of cases of coastal winged stow net fishery has dropped to 757 by 1994 while it was 961 in 1991 and that the number of cases of a sectional winged stow net fishery on the contrary has increased to 302 by 1994 while it was 11 in 1991. Regardless of region, catch per net by year in general has been on gradual increase in 1982 through 1989, but that showed decrease in 1994. From the view of region, the proportion of by - catch of shrimps and blenny is higher in Kyonggi, Chungnam with West Sea and that of anchovy and blenny is higher in Chonbuk, Chonnam, Kyongnam with South Sea. The average proportions of by - catch of small fish for 5 years from 1985 to 1989 are 86.9% for sand lance, 69% for anchovy, 63% for big eyed herring, 51% for blenny, 22% for Southern rough shrimp and 19% for akiami paste shrimp, hence sand lance and anchovy are highly by - catch effective while shrimps is not. Ways to prevent the over fishing of small fish in winged stow net fishery includes reduction of fishing frequency during April and August through November, the very season for small fish, use of meshes large enough for small fish to go through and assignment of fishing area to other than habitats of stationary fish.

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Seasonal Fluctuations in Abundance and Species Composition of Fishes in Cheonsu Bay Using Trap Net Catches (小型定置網資料에 의한 淺水灣 魚類의 水質에 따른 種組成 및 量的 變動)

  • Lee, Tae-Won;Seok, Kyu-Jin
    • 한국해양학회지
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    • v.19 no.2
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    • pp.217-227
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    • 1984
  • Fish samples were collected by a trap net during 1981∼82 at the mouth of Cheonsu Bay to determine seasonal fluctuations in abundance and species composition. Examination of a series of trap net catches indicated that trap net data could be used, at least, for a qualitative analyses of a fish community and for a quantitative study of some pelagic fishes of Cheonsu Bay. Of the 64 species collected, a few temporal components predominated in abundance because of great seasonal fluctuations of water temperature. The early spring catch showed a low abundance value, and two cold weather seasonals, juvenile Enedrias fangi and Ammodytes personatus predominated in number and in weight. The number of species, abundance value in number and in biomass showed a peak in late spring when fishes move into bay for spawning and feeding after over-winterinig in the sea. Three pelagic species or warm weather seasonals, Harengula zunasi , Ammodytes personatus and Konosirus punctatus, predominated in abundance values. In this period night catch was significantly larger than day catch in terms of number of species, abundance in number and in weight Summer data showed a marked reduction of the number of species and abundance due to the loss of spawners probably by mortality or wide dipersion after spawning. A slight increase in abundance was observed in autumn by recruitment of the young-of-the-years. This catch was predominated by three juvenile fishes, H. zunasi, E. japonica and K. punctatus, which were the same species as in spring. The autumn catch showed no significant difference between day and night compositions.

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Composition and Catch Variation of Fishes by a Set Net in the Coastal Waters off Gwideuk, Jeju Island (제주도 귀덕 연안 정치망 어획물의 조성 및 변동)

  • Cha, Byung Yul;Kim, Dae Kwon;Yoon, Jang Taek;Kim, Byung Yeob
    • Korean Journal of Ichthyology
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    • v.20 no.1
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    • pp.28-35
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    • 2008
  • Fishes by a set net in the coastal waters off Gwideuk, Jeju Island were studied to determine species composition and catch variation, 2004. The fishing period conducted by a set net in Gwideuk fishing ground were from April to December. A total of 45,473.2 kg including 21 species was caught during the survey period. Most of them consisted of fishes of 17 species and a few were cephalopods of 4 species. Dominant species were Trachurus japonicus and Siganus fuscescens, 44.3% in the total. And sub-dominant species were Sepioteuthis lessoniana, Seriola dumerili, Seriola quinqueradiata, Loligo bleekeri, Seriola lalandi accounting for 54.4%. Although the number of species had a tendency to decreased from July to December, the catch by a set net was higher in summer and autumn than in spring. Such catch variations were closely related to recruitment of dominant species and also the seasonal variation of fishing ground temperature.

Catching efficiency of LED fishing lamp and behavioral reaction of common squid Todarodes pacificus to the shadow section of color LED light (LED 색광의 음영구역에 대한 살오징어의 행동반응 및 LED 집어등의 어획성능)

  • An, Young-Il;Jeong, Hak-Geun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.47 no.3
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    • pp.183-193
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    • 2011
  • This study made a comparative analysis of behavioral reaction of squid to red (624nm), green (524nm), blue (460nm) & white LED light, its arrival time for the shadow section by making the shadow section in the central section of a water tank just like the bottom part of a squid jigging vessel, and on-site catching efficiency of LED fishing lamp with control fishing vessel. The color LED light showing the highest squidgathering rate as against the shadow section was found to be blue LED light with 39.3% rate under the dark (0.05lx) condition. Under the brighter condition than 0.05lx, white LED light was found to have the highest gathering rate of 41.5%. In addition, it was found that squid gathering rate was high at the shadow section which showed 6.3-fold brightness difference between the shadow section and bright section. As for the arrival time for the shadow section, blue LED light was found to be the fastest in attracting squids in 192.7 seconds under the dark condition while the red LED light was the fastest in luring squids in 164.6 seconds under the bright condition. The ratio of the squid-jigging operation and sailing in fuel consumption of the fishing vessel loaded with LED fishing lamp is about 7 to 1, showing most of the fuel is consumed more in sailing than in squid-jigging operation. As for a catch of squid, the control vessel loaded with MH (Metal Halide) fishing lamp had more catch of 600-7,080 squids than the vessel loaded with LED fishing lamp having a catch of 260-1,700 squids. In addition, even in the comparison of a catch per automatic jigging machine, the catch of the vessel loaded with MH fishing lamp excelled that of the vessel loaded with LED fishing lamp in 6 operations of squid jigging out of 9 operations. The ratio of hand-jigging and automatic jigging machine (one line) in the LED fishing lamp vessel was 1:1.1 excepting the case of having a catch only using an automatic jigging machine, showing almost the same with each other in catches, while in case of a MH fishing lamp vessel, its ratio against hand-jigging was 1 to 5.8, showing hand-jigging excelled in catches.

Dental Treatment of Children with CATCH 22 Syndrome: Case Report (CATCH 22 증후군을 가진 어린이의 치과치료)

  • Kim, Mi Sun;Lee, Soo Eon;Ahn, Hyo Jung;Park, Jae-Hong;Choi, Sung Chul
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.13 no.1
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    • pp.13-18
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    • 2013
  • CATCH 22 syndrome is a one of the most common chromosome microdeletion syndrome with multiple organ anomalies in humans, with an incidence of approximately 1:4,000 to 1:5,000 live births. It is caused by a microdeletion of 1.5 to 3.0 megabases on the long arm of chromosome 22. The phenotypic spectrum of this disorder is wide and various. A 19-year-old patient who showed delayed growth and development (Height; 110 cm, Weight; 18 kg) was referred to our department for the treatment of dental cavities. She was diagnosed as CATCH 22 syndrome in 2004. Physical examination revealed hypertelorism, a short philtrum, thick reflected lips and a small mouth. She underwent cleft palate surgery at 1 year of age and heart valve surgery due to the cardiovascular abnormality at 13 years of age. Convulsive seizures had persisted until 5 years ago but are well controlled at present. Oral examination showed poor oral hygiene, crowding, prolonged retention on #65, 75 and dental cavities on #16, 21, 65, 26, 36, and 46. Cavity treatment and prophylaxis were performed under general anesthesia. Also continuous follow-up checks have been carrying out with the periodic prophylaxis and dental home education. Problems with numerous cavities and gingivitis which can lead to specific risks are common for CATCH 22 syndrome patients. It is therefore of great importance that these patients are referred to foremost physician and dental specialist for the oral care. In addition, preventive treatment targeting the risk of dental cavities and gingivitis is especially important and, as the syndrome involves many different medical problems, the dental treatment should be carried out in collaboration with the patient's physician.

Environmental Character and Catch Fluctuation of Set Net Ground in the Coastal Water of Hanlim in Cheju Island III. Environmental Character and Catch Fluctuation (제주도 한림 연안 정치망 어장의 환경특성과 어획량 변동에 관한 연구 III. 어획량변동과 환경요인)

  • KIM Jun-Teck;JEONG Dong-Gun;RHO Hong-Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.105-111
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    • 1999
  • To investigate the relationships between ocean environmental characteristics and thechange of the catch, we analyzed various environmental factors such as mean temperature, salinity, current vectors, lunar day and wind vectors from 1995 to 1996 and the catch fluctuation of Hanlim set net from 1994 to 1996. The results are as follow ; 1) The proportion of fishes caught in Hanlim set net is highest for horse mackere1 ($69.2\%$) and is followed by common mackerel ($18.4\%$), hair tail ($5.6\%$), squid ($2.7\%$) and rabbit fish ($1.4\%$) in order. Two peaks in the monthly catch appeared in June and October in the operation period of May- December. 2) The flow direction was northward in flood time and southeastward in ebb time around the Hanlim set net. Thus, the vortical mixing of sea water was active and continued for more than 3 hours. In addition, mean daily temperature was low due to the presence of middle and bottom water in offshore. Increase in salinity or high salinity of sea water provides a favorable condition for catches of fishes. Catches in the first quarter and the last quarter of the moon were larger than that in full moon and the last of the month. In particular, when south or southeasterly wind velocity reaches about 3$\~$6.5 m/s, the possibility of catches increases.

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A Comparative Analysis of Maximum Entropy and Analytical Models for Assessing Kapenta (Limnothrissa miodon) Stock in Lake Kariba (카리브호수 카펜타 자원량 추정을 위한 최대엔트피모델과 분석적 모델의 비교분석)

  • Tendaupenyu, Itai Hilary;Pyo, Hee-Dong
    • Environmental and Resource Economics Review
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    • v.26 no.4
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    • pp.613-639
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    • 2017
  • A Maximum Entropy (ME) Model and an Analytical Model are analyzed in assessing Kapenta stock in Lake Kariba. The ME model estimates a Maximum Sustainable Yield (MSY) of 25,372 tons and a corresponding effort of 109,731 fishing nights suggesting overcapacity in the lake at current effort level. The model estimates a declining stock from 1988 to 2009. The Analytical Model estimates an Acceptable Biological Catch (ABC) annually and a corresponding fishing mortality (F) of 1.210/year which is higher than the prevailing fishing mortality of 0.927/year. The ME and Analytical Models estimate a similar biomass in the reference year 1982 confirming that both models are applicable to the stock. The ME model estimates annual biomass which has been gradually declining until less than one third of maximum biomass (156,047 tons) in 1988. It implies that the stock has been overexploited due to yieldings over the level of ABC compared to variations in annual catch, even if the recent prevailing catch levels were not up to the level of MSY. In comparison, the Analytical Model provides a more conservative value of ABC compared to the MSY value estimated by the ME model. Conservative management policies should be taken to reduce the aggregate amount of annual catch employing the total allowable catch system and effort reduction program.

Stock Assessment and Optimal Catch of Blackfin Flounder Glyptocephalus stelleri in the East Sea, Korea (한국 동해안 기름가자미(Glyptocephalus stelleri)의 자원평가 및 적정어획량 추정)

  • Sohn, Myoung Ho;Yang, Jae Hyeong;Park, Jeong-Ho;Lee, Haewon;Choi, Young Min;Lee, Jae Bong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.598-606
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    • 2013
  • The blackfin flounder Glyptocephalus stelleri is a commercially important species in the East Sea of Korea, but its catches and biomass have decreased gradually in recent years. This study estimated the optimal catch (acceptable biological catch, ABC) for the effective management of this species by estimating population ecology parameters and the stock biomass of blackfin flounder in the East Sea of Korea. The estimated instantaneous coefficient of total mortality (Z) of blackfin flounder was 1.0542/year, the survival rate (S) was 0.3485, and the instantaneous coefficient of natural mortality (M) was 0.3637/year. From the values of S and M, the instantaneous coefficient of fishing mortality (F) was calculated to be 0.6905/year. The age at first capture was 1.304 years, and the total length was 11.5 cm at that time. On the basis of these parameters, the annual biomass was estimated by a biomass-based cohort analysis using annual catch data in weight by year for 1991-2012 in the East Sea of Korea. The annual biomass peaked in 1997 at about 12,800 mt and then subsequently declined continuously to a level of 10,500 mt in 2004 and to 9,800 mt in 2011 and 2012. The maximum sustainable yield and $F_{0.1}$ were estimated as 3,547 mt and 0.3595/year, respectively. Using these estimations, the ABC was estimated to be 3,571 mt in tier 5, 3,397 mt in tier 4, and 2,622 mt in tier 3.

Variations of Catch and Fish Species in the Adjacent Fishing Ground of Ceramic Artificial Reefs Constructed on the Coastal Area of Geomun-do, Korea (한국거문도 연안에 시설된 세라믹 어초 인접 어장에서의 어획량과 어획종 변동)

  • Park, Seong-Wook;Kim, Dae-Kweon;Lee, Jeong-Woo;Ahn, Hee-Chun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.40 no.4
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    • pp.295-303
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    • 2004
  • In order to estimate the effect of ceramic artificial reefs on the fisheries resources enhancement, we have studied the variation of catch and species, which were caught by trammel net on the three fishing grounds of ceramic artificial reef, natural reef, and control(non-reef)in the coast of Geomun-do, Korea from 2001 to 2003. Catch per unit effort (CPUE ; g/panel) of fishing ground with the ceramic artificial reef area was 1,621.9g, it was about 67.9% higher than the natural reef area 333.3% higher than the control area. The catch of fish with the ceramic artificial and the natural reef area was not significantly different based on statistical analysis of Tukey test, whereas the relationship between the ceramic artificial reef and the control area was significantly different (p<0.05). Monthly mean number of species caught by the artificial reef area, the natural reef area and the control area was no difference by ANOVA test. The catch of fish was highest in November and lowest in May, whish was associated with the natural reef and the control area. The dominant species were demersal fishes living around rock such as Pagrus majir, Thamnaconus modestus, Stephanolepis sirrhifer, Pleuronichthys curntus, and Ostracion cubicus in the artificial reef area, but demersal of migratory fishes in the natural reef and the control area.

Fishing investigation of vertical bottom longline fisheries in sea mount of central northern Pacific (북태평양 중부 해산어장에 있어서 저층 선주낙의 어획실태)

  • Oh, Taeg-Yun;Kim, Yeong-Seung;Cho, Sam-Kwang;Kim, In-Ok;Choi, Seok-Gwan;Koh, Jeong-Rack;Yang, Won-Seok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.3
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    • pp.188-198
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    • 2005
  • This study was conducted to survey the catches of vertical bottom longline fisheries in the sea mount of central northern Pacific($30^{\circ}-42^{\circ}N$, $170^{\circ}-175^{\circ}E$), during the period of July 1 to August 25,2004 by commercial fishing vessel. The number of 57 test fishing was carried out in the central northern Pacific during 43 days and the total catches were 21,092.4kg as 19 fish species, CPUE/day and catches/day were 185 baskets and 490.5kg, respectively. Main fish species caught from the experimental fishing were Squalus mitsukurii (66.3%), Coelorhyrchus asperocephaius (11.7%) and Helicolenus avius (9.8%) and, average inside diameter for fish mouth was 4.0cm over. Catch ratio according to each fishing ground was the order of F, D, J, B and C. Catch ratio fur water depth was the order of 450-500m, 350-400m, 300-350m, 400-450m, 1000-1100m and 500-550m and, main species by water depth was Squalus mitsukurii for 300-400m, Etmopterus lucifer for 300-550m, Coelorhyrchus asperocephaius far 1,000m over. Catch ratio according to the kind of hooks was higher at the hook no.6 for Squalus mitsukurii and no. 5 for Etmopterus lucifer and, catch ratio by baits was higher at squid for Squalus mitsukurii, saury and eel for Helicolemus avius and saury for Etmopterus lucifer. Accordingly, it is thought that the extension of fishing hours is needed with the reduction of damage and loss for fishing gears during fishing operation.