• Title/Summary/Keyword: Baits

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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.

Development of artificial bait for octopus drift line (문어 흘림낚시용 인공미끼 개발)

  • An, Young-Il;Arimoto, Takafumi
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.43 no.4
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    • pp.291-300
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    • 2007
  • The crayfish-shaped artificial bait for octopus drift line is manufactured, into which is made to insert ordinary bait. The effects of the artificial bait are confirmed through the analysis of octopus' behavior in the laboratory in comparison with the existing bait of pig-fat skin, and the investigation of the octopus catch on the sea, and in addition, the examination of the water quality in relation to the bait to be inserted into the artificial bait is done together. The artificial bait is red in color, 10.5cm in the length of the body, and 29g in weight. The octopus behavior in relation to the bait in the laboratory has shown a good result in which more than 30% of the octopuses rushed to the artificial bait. In the analysis of the octopus sitting time by the bait, the octopus stayed longer with the artificial bait(63.7%) than the pig-fat skin(25.1%). The octopus sitting time at the artificial bait inserted with frozen squid(48.8%, 44.6%) is shown to be longer than that of the pig-fat skin(36.9%) or boiled fish paste(21.2%). In the analysis of sitting frequency to the bait, the case of the artificial bait(total 17 times) was more than that of the pig-fat skin(total 3 times), and the case of the artificial bait with frozen squid attracted the octopuses more frequently than that of the pig-fat skin or the boiled fish paste. In the field experiment, the fishing boat A(Manseon-ho, 1.22tons) caught the total 93 octopuses, while the fishing boat B(Ilho-ho, 0.73tons) caught the total 154 octopuses, all of which weighed less than 9.0kg. In the comparison with the total catch, the case with the artificial bait was a little higher than that of the pig-fat skin($^{**}p\;<\;0.05$). In the analysis of the water quality in relation to the baits, the COD showed the descending order of frozen squid(0.57mg/g), boiled fish paste(0.18mg/g), and pig-fat skin(0.10mg/g), and the case with frozen squid was the highest and the case of the pig-fat skin, lowest. The total phosphorus, like the COD, showed the highest in frozen squid(0.02mg/g), and in case of the total nitrogen, unlike the COD, the pig-fat skin was shown to be the highest(0.006mg/g).

BIOLOGICAL STUDIES ON THE FRESH-WATER SHRIMPS IN KOREA 3. The Food an4 Growth of the Larvae of Palaemon modeatus (한국산 민물 새우류에 관한 생물학적 연구 3. Palaemon modestus 유생의 먹이와 성장)

  • CHUNG Kyung-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.4 no.2
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    • pp.55-60
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    • 1971
  • There are a lot of kinds of shrimps for fishing baits, but Palaemon modestus is dominant species in the Karak River. The ecology in the natural environments was reported by the author (1970) and this work is an elemental task for the larval stage in shrimp farms. Shrimps were collected from the Karak River and carried to the laboratory. Hatched larvae were reared from June 6 to June 24, 1970 for pre-experiment, and main experiment was provided from August 10 to August 24, 1970. The following is a summary of the results: 1. Hatching period in the laboratory water tank was eight hours ($20^{\circ}C\~20.9^{\circ}C$). 2. The larvae died off from the sixth day after hatch without food. 3. Feeding begins on the third day after hatch. 4. The relationship between the density of food and the consumption was not concerned when the number of Artemia nauplii was 2 to 6 per ml of water. 5. The relationship between the day (X) and the food (Y) is: $$Y=6.49824X^{1.8384}$$ 6. The carapace growth curve is: $Y=1.1608X^{0.10024}$ 7. The relationship between the food (X) and the body length (Y) is: $$Y=2.8114X^{0.12767}$$ 8. The relationship between the carapace length and the body length(Y) is : Y= 3.7564X-0.4601

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Scouting Methods for Larva and Adult Alfalfa Weevil, Hypera postica (Coleoptera: Curculionidae) on Chinese Milkvetch, Astragalus sinicus L. (자운영답에서 알팔파바구미 유충 및 성충 조사방법)

  • Lee, Heung-Su;Kwon, Jin-Hyuk;Chung, Bu-Keun;Kim, Tae-Sung
    • Korean journal of applied entomology
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    • v.51 no.1
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    • pp.67-72
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    • 2012
  • This study was conducted to evaluate the scouting methods for larva and adults of the alfalfa weevil, $Hypera$ $postica$ Gyllenhal on Chinese milkvetch, $Astragalus$ $sinicus$ L. in the field. Three sampling methods, shake-bucket, shake-picking, and a sweeping net were evaluated for collecting alfalfa weevil larvae. We found significant differences among scouting methods and date in all survey fields. Sweep-net sampling was less able to detect small larvae than large larvae, which were not detected until early April whereas the shake-bucket, and shake-picking methods efficiently collected larvae from middle March. A Pitfall trap with three different baits - no bait, kidney bean seeds and sprouting kidney beans were compared for collection efficiency of alfalfa weevil adults. Collection efficiencies were significantly different by bait(p<0.018). Traps baited with sprouting kidney beans were the most efficient for collecting the alfalfa weevil. The number of alfalfa weevil caught was not significantly different between kidney bean seed and no bait in the pitfall trap. Therefore, the shake-bucket method for larvae and a pitfall trap baited with sprouting kidney beans for adults are recommended for scouting of the alfalfa weevil in a Chinese milkvetch field.

The Foundation of the Colonialism: John Locke, America, and the tragic History of the Indigenous (식민주의의 기초 : 존 로크와 아메리카, 인디헤나의 수난사)

  • Hur, Jay-hunn
    • Journal of Korean Philosophical Society
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    • v.130
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    • pp.381-414
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    • 2014
  • This paper aims to elaborate on the foundation of the colonialism, which comes from Natural Laws by John Locke and the extermination of the indigenous. John Locke develops his political doctrines considering Natural Laws as the logical, metaphysical supposition. He assumes Natural Laws to be the logical presupposition, but is interested in North America. This is evidently seen in his works according to research outcomes. His 'possessive individualism' discusses exclusion and extermination, on the bound of natural laws and natural state. The person without possessive rights is excluded, the people without effective farming is forfeited. Then acculturation is the justifying of slavery and suggestive of extermination. In the possessive individualism of bourgeois society, that is, private property, man is annulled aboard. That is colonialism comes from, which destroys all the cultures but its own cultures. It is Locke who is the first thinker of the imperial. In the thought of Locke found we in profane terminology projected for the world imperial. After Locke, colonialism has been appeared in the guise of racism in the eighteen century, especially in the universal history of system of philosophy, sometimes in the face of orientalism on all sides. The ideas of colonialism and imperialism have been absolutely for the West. In the totally administered society nowadays, the hope of redemption has been made impossible from the origin. From the beneath, operated and practiced the program of deletion of race, its ethnic cleansing is a mere case. Locke's thought for the human rights is consisted of property and freedom in mankind, but it ground baits for its bloodied symposium with words and consults. 'Our word is our weapon', this is wording of one ethnic that is in nearing extermination.

The Behaviour of Fishes to the Traps and Their Catch Ability (통발에 대한 어류의 행동과 어획성능에 관한 연구)

  • KO Kwan-Soh;KIM Dae-An
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.1
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    • pp.15-23
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    • 1984
  • Difference of the entering and the escaping behaviour of shrimp(Palaemon pacificus) to the model traps were observed in accordance with netting materials, baits, type of traps and slope of flapper, and gathering responses were also investigated on the odour of bait extracts in the aquarium as the preliminary test. In order to investigate the difference in catch according to type and structure of traps those designated from A to E were made of iron frames and nettings. The type A was a conical shape with two entrances at its both sides and the others were square piller shape with one entrance at their upper surface(type B) or two entrance at their both ends(type C, D and E). However th type D and E were connected with flapper and the thye E was made by attaching iron frames of same height under the type D. The traps were prepared 10 each and so a total of 50 traps were used in the experiment at sea. The main species caught was Charybdis japonica, but Astroconger myriaster was also caught fairly. The catches of these species were significant in difference between the types of traps. That is, Charybdis japonica was caught more in type A, C and D than others and less in type B and E, and Astroconger myriaster was caught more in type A and D and less in type B and E. However the catch of Astroconger myriaster in type C, even if less than that in type A showed no significant difference with the other traps. The total catch of Charybdis japonica and Astroconger myriaster was almost same in order with the catch of Charybdis japonica. The type B and E seemed to be difficult in entering of fishes into them. However, the type A and C seemed to be easy not only in entering, but also in escaping. Especially, the type C showed more escaping. On the other hand, the type D seemed to be not so easy in entering of fishes as type A and C, but very difficult in escaping. Consequently, the escaping of fishes from the traps seemed to be more difficult in conical traps than any other traps. The catches might be influenced by the bait with bag compare to without bag and also the immersed time of traps into water for fishing.

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Bionomics and a Lana Sampling Method of Coppery Wireworm, Selatosomus puncticollis (Motschulsky), (Coleoptera: Elateridae) in Potato Field (청동방아벌레(Selatosomus puncticollis Motschulsky)의 생태적 특성 및 감자포장내 유충밀도 조사법)

  • Kwon, Min;Park, Cheon-Soo;Lee, Seung-Hwan
    • Korean journal of applied entomology
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    • v.43 no.3 s.136
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    • pp.195-200
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    • 2004
  • The occurrence pattern and bionomics of Selatosomus puncticollis (Motschulsky) were surveyed in three net house (6$\times$70m) in the field and in a laboratory ($20^{\circ}C$, RH$75\%$, L16/DB). Emergence of hibernated adults of S. puncricollis started from early May, reached peak at early June and diminished in late June. Occurrence rate to total number was $42.1\%$ in early June and $31.7\%$ in late May, when most of hibernated adults emerged at these periods. Adults started to oviposit from mid June, and eggs hatched from early July Larvae turned into pupae from mid July and emerged to adults from mid August. Egg-period was 23 days and pupal period was 21 days. It is estimated that preovipositional period and larval period were approximately 10 months and 30 months, respectively. Wireworms were distributed at the soil depth of 10-5 cm, $56.8\%$ in 1997 and $45.8\%$ in 1998. To establish bait techniques to attract wireworms in the soil, six baits: pieces of potato, carrot, and sweet potato, wheat grains, corns, and flour dough wrapped with gauze, were buried at 15 cm of soil depth, and collected after 5 and 10 days. The numbers of wireworms attracted by potato pieces, wheat grains and sweet potato pieces after 10 days were 1.8, 1.6, and 1.4/bait, respectively. Therefore, burying potato pieces at 15 cm of soil depth and collected after 10 days could be recommended as a wireworm baiting technique.

Chemical Synthesis and Orientation Disruption Bioassay of Sex Pheromone of the Oriental Fruit Moth, Grapholita molests (Busck) (복숭아순나방(Grapholita molests) 성페로몬 합성과 유인력 교란생물검정)

  • Kim, Yong-Gyun;Bae, Sung-Woo;Bae, Soo-Il;Yoon, Hyang-Mi;Hong, Yong-Pyo
    • Korean journal of applied entomology
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    • v.45 no.3 s.144
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    • pp.309-316
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    • 2006
  • Three sex pheromone components (cis-8-dodecenyl acetate (Z12Ac), trans-8-dodecenyl acetate (E12Ac), cis-8-dodecenol (Z12OH)) of the Oriental fruit moth, Grapholita molesta, were chemically synthesized. Especially to increase the composition of cis-stereoisomer, a triple bond intermediate was hydrogenated at $-20^{\circ}C$ with catalytic $Pd/BaSO_{4}$. The resulting product consisted of the acetates with a stereoisomer ratio in 92:8 (Z:E). The biological activity of the synthesized pheromone compounds was analyzed both in male responses and orientation disruption. The indoor pheromone effect was determined by male flight behavior showing wing movement in response to lure. Different mixtures of the synthetic pheromone components were prepared by mixing acetate and alcohol components in 100:0, 99:1, and 90:10 (g/g) and tested with a comparison of a standard commercial pheromone lure. The highest pheromone effect was observed in only acetate mixture (100:0) and the effect was reduced with the addition of the alcohol component. This indoor pheromone effect could be observed in field monitoring trial, in which 100:0 mixture showed the highest trap catches. Orientation disruption assay was conducted indoor by using a cage, in which the center had a commercial lure on sticky plate and the four candidates were placed at 6 cm away from the central lure on each of four directions. Test males were released to the arena during overnight (12 h) and then the caught males on the sticky plate were counted. The synthesized pheromone as well as the commercial pheromone showed 100% orientation disruption. However, the orientation disruption effect was reduced with decrease in the number of the surrounding disrupting pheromone baits. These results clearly suggest that the synthesized sex pheromone of G. molesta is biologically active and can be used for field mating disruption.