• 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).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.190-197
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• 2019

This study investigated the luring effect of the sardine bait, which is used to catch octopus with pot, as the preliminary study for the development of alternative bait for octopus pot. The soaking time for bait was divided into "5 days or less" and "11 days or longer" The number of times octopus entered the pot with bait and the empty pot was investigated under dark adaptation and light adaptation processes and the distribution of tank section was investigated under light adaptation process. The case of "11 days or longer" sardine soaking time showed higher rate of distribution in the section of pot with bait compared to the case of "5 days or less" In the case of "5 days or less" soaking time, the number of times the octopus entered the pot with bait was similar to that it entered the pot without it even during dark adaptation and light adaptation. However, in the case of "11 days or longer", the octopus entered the pot with bait more quickly than the pot without bait and more frequently during dark adaptation hours. There were cases where the octopus did not enter any pot. In the case of "5 days or less", with less decomposition of baits, the octopus entered the empty pot more during light adaptation process, and it appeared that the pot was used as a hideout.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.135-140
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• 2000

Matsucoccus thunbergianae is a major insect pest of Pinus thunbergiana in southern Korean peninsula. To study the flight behavior of M. thunbergianae males responding to the synthetic pheromone, five sticky traps were placed on a bamboo pole at various heights, between 0.1m and 2.0m above ground. A bait impregnated with the synthetic pheromone was placed at 0.1m, 1.0m or 2.0m above ground and the number of male catches on each trap was counted. In an open area, numbers of males caught per trap were not different between heights when the bait was placed at 2m or 1m above ground ; when the bait was placed at 0.1m height, male flight was aggregated near the ground. In a forest with low crown closure, trap catches on five traps on the same bamboo pole were not different one another when the bait was placed at 2m height, but most males were flying near the bait when it was placed at 1m height. In a dense pine forest, most males were flying around the bait regardless of the bait position. In all three places, most males were caught on the trap near the ground when the baits were placed 0.1m above ground. Thus, for monitoring the frontal zone of infestation of the scale, placing the pheromone trap near the ground was considered the most efficient. When the males perceived pheromone, they tended to fly in the air with low wind speed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.316-326
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• 2011

In this study, the entrapped number is investigated on the UV light with different illuminance to fluorescent bait cage for swimming crab in order to find the appropriate illuminance which has the best attraction effect of fluorescent bait cage for pots. In addition, preference to the light, arrival time and residence time at light area are compared and analyzed to fluorescent bait cage and non-fluorescent bait cage for American lobster at the UV light and ordinary light according to the illuminance condition. Pot with red non-fluorescent bait cage at the no lighting (<0.01lux), pot with blue fluorescent bait cage at the 20W UV lighting (0.16lux) and pot with blue fluorescent bait cage at the 30W UV lighting (0.22lux) were soaked for 6 hours and the entrapped number of swimming crab was examined. The mean entrapped number of swimming crab in pot with red non-fluorescent bait cage at the no lighting (<0.01lux) was 1.0, but the mean entrapped number of swimming crab in pot with blue fluorescent bait cages at the 20W UV lighting (0.16lux) and 30W UV lighting (0.22lux) were 1.4 and 0.4, respectively (P<0.05). The rate of preference to the blue fluorescent bait cage at the UV lighting shows 1.6-4.8 times higher than that of preference to the red non-fluorescent bait cage at the ordinary lighting. In addition, The rate of preference to the blue fluorescent bait cage at the UV lighting is higher when the illuminance of ordinary light is same as or is lower than that of UV light (P<0.05). However, the preference to the light depending on gender shows no significant difference (P>0.05). The arrival time to UV light area of lobster is shown as 1.2-2.4 times faster than that to ordinary light area. Generally, it is shown that arrival time to UV light area is faster than the arrival time to ordinary light area when the illuminance of ordinary light is the same as or lower than that of UV light (P<0.05). However, arrival time to the light area depending on gender shows no significant difference (P>0.05). The residence time at UV light area of lobster is 1.2-1.7 times longer than that at ordinary light area. The residence time depending on different illuminance of ordinary light and genders showed no significant difference (P>0.05).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.3
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• pp.214-222
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• 2010

The paper presents investigations on to which degree the sinking speed of longlines is influenced by type of bait, bait sinking orientations and anchor weights. The main aim of this study is to obtain further insight in the ocean current displacement phenomena in demersal longlining. The sinking speed is one of the main factors deciding the current displacement. In an ongoing project, sinking speed experiments with longlines with 6 kg and 10 kg anchor weights have been carried out in the Trondheim fjord. The longlines used in the first experiments were rigged without bait and hook. The results of these experiments with two different anchor weights have revealed only a slight difference in the sinking speed, except for the part near to the anchors, even though the sinking speed of longlines in general is supposed to be much influenced by the anchor weights. The reason for the obtained result is supposed to be that the experiments have been carried out at relative shallow waters. Further studies have included bait sinking experiments in the flume tank. The experiments showed that the drag coefficient of "fillet type (flat)" bait varied from 0.763 to 1.735, while it for "elliptic type" bait varied from 0.62 to 1.483. Other activities have included calculation of the sinking speed of longlines as a function of the established resistance coefficients of bait of various shape and size for commercial longlining. The calculated sinking speed of a longline with the fillet type bait was found to be 12.4 to 16.5% lower than for a longline without bait.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.3
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• pp.202-212
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• 2020

In order to replace sardine baits for octopus pot, an efficacy experiment to lure with alternative bait (fermented skate or chicken skin in artificial crab or northern clam) pots and sardine pot were conducted in a circular water tank. The soaking time of the sardine bait was divided into two categories: six days or less and seven days or more. The behavioral response of octopus to the artificial bait pots and sardine pot were investigated. In the comparison of the luring effects between pots with fermented skate inside artificial crab or northern clam and sardine pot, the pot with artificial crab + fermented skate had better results than the other pots in the section distribution (31.6%) and the number of times the pot was entered into (20.0%) (p > 0.05). In the comparison of the luring effects between pots with chicken skin inside artificial crab or northern clam and sardine pot, the pot with northern clam + chicken skin had better results than the other pots in the section distribution (22.6%) and number of times the pot was entered into (55.6%) (p < 0.05). The results were also better compared to those of pot with artificial crab + fermented skate. From these results, it seems that in the luring effect aspect, sardine bait can be replaced with artificial bait consisting of chicken skin inside northern clam.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.570-580
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• 2017

In this study, we designed a fishing system to reproduce the underwater movement of the living Sword tip squid (Loligo edulis) used as bait in the red seabream long line fishery, and conducted the experiment of the fishing operation in 2 ways, i.e., a pole and line fishing method (fishermen) and a bait control fishing system used at fishing sites. Based on the catches in fishing operation, the experiment was conducted over a six times (2014 & 2015), and then 107 fishes were caught by the line fishing method while 57 fishes were caught by the bait control fishing system. The fishermen method actively controlled the speed of gear movement upward and downward while checking the reaction of red seabreams to the bite in the process which a jerk was transmitted to single line hook fishing gear manually. The bait control fishing system is a passive method which fishermen visually check only the movements at the end of fishing pole, enabled differentiation of bite reactions of red seabream during fishing operation. Thus, the difference between fishermen method and the bait control fishing system was found to about 53.3% in the catches. We confirmed the possibility of a site fishing operation based on the bait control fishing system designed newly as a result of this study. Improvement is in several areas for commercialization at the site. This fishing system is expected to be able to find wide-ranging applications as a new labor-saving method for the fishing red seabreams if it is applied to the fishing sites after aforesaid process.

• Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.336-343
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• 2023

This study aimed to know the response of deep-sea squid Sthenoteuthis oualaniensis to the light colors of the artificial bait. This experiment used the commercial artificial flashlight baits commonly sold in the fishing shop. The bait has several different light color combinations. The light colors were modified into several light colors by inactivating certain colors and used as treatments. The study is expected to be able to find flashlight bait's most effective color for squid fishing. We applied red-green, green, blue, and commercial bait lights in this study. Each treatment has 3 replications. The effect was expressed as the amount of squid caught. Data were analyzed by one-way analysis of variance. Results showed a significant effect on the number of squid catches. There was significantly different squid catches among the treatments. It indicates that this artificial flashlight bait could be developed to maximize squid catches. This finding can be used for the local fishermen's income and the squid fisheries development.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.20-30
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• 2008

In order to evaluate the biodegradability of bait used in the pot for swimming crab, water tank experiments were conducted. Mackerel is the most commonly used natural form of bait to catch the swimming crabs, and therefore was used in this experiment for the biodegradability according to the manufacturing process of the bait. From the biodegradability test on chemical oxygen demand(COD), total nitrogen(T - N), total phosphorus(T - P), ammoniac nitrogen, nitrite nitrogen and nitrate nitrogen per unit weight of the bait based on the production rate and the accumulated amount of pollutants, it was concluded that the smaller the size of the mackerel pieces, the higher the production rate and accumulated amount of organic matter and nutrients which was unfavorable to water pollution. The amount of pollutants released from the intestine of the tuna was similar with that from the whole mackerel. For the operation period of 111 days, the accumulated concentrations of tested pollutants from the tuna which were 67.3 mgCOD/g d, 86.4 mgT N/g d, 3.1 mgT - P/g d, were almost half comparing with those from the mackerel which were 65.7 - 94.4 mgCOD/g d, 83.8 - 109.4 mgT - N/g d, 3.1 - 5.2 mgT - P/g d. The amount of pollutants released from the intestine of the tuna was slightly less than that from the mackerel that was cut into 8 pieces. but more than that from the mackerel which was not cut into pieces. Therefore, it can be concluded that the key factor in determining water pollution potential is not the kind of bait, but the processing or preparation method used.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.270-276
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• 1997

Bait formulations containing 50% micro-capsuled fenitrothion, 2.0% hydramethylnon or 0.8% chlorpyrifos were evaluated in an 8 week field experiment against German cockroach, Blattella germanica(L). In German cockroach infested 15 restaurants, micro-capsuled fenitrothion (avg. 82.8%) was more effective at reducing adult German cockroach populations than chlorpyrifos (avg. 68.4%), but was about equally as effective as hydramethylnon(avg. 86.1%). The baits of micro-capsuled fenitrothion (avg. 76.5%), hydramethylnon (avg. 82.8%) and chlorpyrifos (avg. 74.9%) almost equally reduced nymphal German cockroach populations in the field. Most baits remained in the bait stations at the heavily infested restaurants after the 8 week treatments. However, the contents of hydramethylnon baits had been subject to significantly greatest consumption (0.72g) and the remaining bait was on the average of 57% by German cockroaches. It was assumed that the previous phenomenon of extra consumption of bait was explained by the infesting cockroaches continuously taking these baits because of the mode of action, the bait food material and the population densities of German cockroaches.