• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.624-631
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• 2001

The relationship between the catch of squid, Todarodes pacificus, according to the jigging depth and underwater illumination by fishing lamps was investigated during nighttime operations off-Tusima Islands in November 1994 and off-Oki Islands in November 1995. We used echo sounder to observe the distribution of squid. Echo images on the echo sounder showed the distribution of squid at the water layer of 50 meter depth at the beginning of jigging operation. After the time elapsed, a continuous dense image had moved to the layer of 60-80 meters jigging depth. A larger number of squid were caught by jigging machines set at a lowest depth of 90 meters, when it compared with machines set at a 60 meters. However, Catch increased around 60 meters jigging depth, when fishing lamps output were switched to 24 kW halogen lights:.The underwater illumination, under the each light power of fishing lamps of squid jigging boat was continuously measured with an underwater illuminometer. Values of the underwater illumination, when schools were distributed from 60 to 80 meters, ranged from $3.0\times10^{-2}lx\;to\;3.4\times10^{-3}lx$ in average at $80\~360$ kW fishing lamps output of squid jigging boat.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.4
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• pp.303-309
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• 2019

This study identified the characteristics of squid jig in korea waters by investigating the effect of color and luminous performance of squid jig on the catch of squid and experimenting the result of jig according to green jig or white jig, and whether using luminous or not were tested in the sea to improve the jig of squid jigging. For this purpose, a total of 13 sea experiments were conducted using T/S No. 2 Galmaegi. As a result, 341 squids were caught. Among them, 221 squids were caught by green jig (64.8%), 64 squids were caught by white jig (18.8%), 41 squids were caught by green luminous jig (13.8%), and nine squids were caught by white luminous jig (2.6%). The green jig commonly used in jigging vessel was most effective, and luminous jig was less effective than that non-luminous jig. The squids caught were Japanese flying squid (Todarodes pacificus), swordtip squid (Loligo edulis) and spear squid (Loligo bleekeri), and no significant characteristics were found according to the color of jig and the presence of luminous.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.3
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• pp.208-217
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• 2013

Decoys for automatic jigging machines, the body part of a squid hook, have been developed in small and existing sizes in consideration of squid food, color blindness, and retinomotor responses and in utilization of pearl pigment, PP of high transparency, and combined mixture. In comparison of the developed silver-white decoy and existing decoys, the optical characteristics were examined, and the fishing performance of small size silver-white squid hooks was assessed in application of 4 fishing boats with the squid automatic jigging machine and metal halide fishing lamp in July, 2012. The luminances of the three squid hook colors-green, dark green and silver-white-increased as the intensity of illumination increased. Among these, the increase of silver-white was particularly distinguished. As to the average contrast of squid hooks, that of silver-white was 10.33, which was the highest, and then green 1.86 and dark green -0.10 in the order. As to the fishing performance of the silver-white hook, that of the 202 Geumyeong-ho and 101Yongjin-ho which caught squids were similar to that of the existing green hook and was relatively low in the case of the Dongbu-ho. However, that of the Haengbok-ho which caught relatively small squids whose average length was 19.9cm and installed silver-white hook in all automatic jigging machines was significantly excellent. In order to enhance the fishing performance of small size silver-white hooks, therefore, it would be effective to install in every automatic jigging machines of fishing boat and to start fishing before July by which small squids are caught.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.3
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• pp.211-218
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• 2017

The catch performance of the silver-white jig for automatic jigging machine, developed to improve the effectiveness of LED fishing lamp in catching squid, was compared to that of the conventional green jig. The vessels used in this investigation were Haesong-ho (A-vessel), a training vessel of Gangwon State University and Haengbok-ho (B-vessel), a commercial fishing boat. In the case of the A-vessel, five to eight automatic jigging machines were used in the fishing operation with a 31.3 kW LED fishing lamp in summer. As for the B-vessel, fourteen automatic jigging machines were used with a 43.2 kW LED fishing lamp in autumn and winter. The results showed that the catch performance of the silver-white jig was similar to that of the green jig in the case of the A-vessel (p>0.05). However, in the case of the B-vessel, the catch performance of the silver-white jig was superior to that of the green jig in both winter (p<0.05) and autumn (P<0.001). Based on the catch performance results regarding the B-vessel in autumn, it is expected that the annual income increase that can be earned by using the silver-white jig will be KRW 26,385,000.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.3
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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.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.395-403
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• 2013

Fishing efficiency of the squid jigging vessel using the LED and metal halide fishing lamp combination was analyzed to reduce the cost for fishing operation utilizing the fishing light system for high degree of efficiency in the squid jigging fishery (one of the representative coastal and offshore fisheries in Korea). This study aims to improve the nature of existing LED lamps and to develop fan-shaped LED lights having 180W of power and ${\pm}45^{\circ}$ angle of light intensity distribution. The marine experiment for making a comparison of their fishing efficiency was tested by a 9.77 tons fishing vessel from Oct. through Dec. 2012. As a result, experimental fishing vessel showed slightly higher fishing efficiency than the average of metal halide lamp-equipped vessel and 20% energy savings. This means that the combination of LED and metal halide lamps would provide an efficient way to lower energy consumption while maintaining fishing efficiency.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.385-394
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• 2013

This study has conducted a comparative analysis on the fishing efficiency of LED fishing lamps by squid jigging vessels, the Yeongrak-ho (16 tons) and Somang-ho (9.77 tons), which operated during September and October 2010 and during October 2011, comparing with MH (Metal Halide) fishing lamp-equipped fishing vessels. This study has also examined vessel's fuel consumption level. The light powers of LED fishing lamps of the Yeongrak-ho and Somang-ho were 25.8kW and 32kW, respectively. Those of the MH fishing vessels, that is, the MH fishing lamp-equipped fishing vessels, were 105kW and 81kW, respectively. The average squid catch in number of an LED vessel, Yeongrak-ho, was 39.2% of the MH fishing lamp-equipped fishing vessels; however, that of the Somang-ho improved to 78.7% of the MH fishing lamp-equipped vessels. Average catch in number by Yeongrak-ho crew was 2.6 times more than catch in number by automatic jigging machines. Average catch in number by MH fishing vessel crew was 1.8 times more than that by automatic jigging machines. An LED vessel, Yeongrak-ho's fishing rate was 17.5%~152.2% of the MH fishing vessels, that is, 61.1% on average, in comparison of combined catch in number per automatic jigging machine and per crewmember. Somang-ho's fishing rate was 6.7%~127.6% of the MH fishing vessels, that is, 73.1% on average. The average fuel consumption level of the Somang-ho, throughout its departure from to arrival at the port, was 475.7l, and that during fishing hours was 109.6l, or 23.0% of the total fuel consumption level. Somang-ho's fuel consumption level per fishing hour was 9.7l on average.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.294-303
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• 2008

Squid jigging fishery is very important in that there are about 1,000 jigging vessels more than 10 tonnage and about 5,000 ones less than 10 tonnage in Korea. But the cost of oil which is used to light fishing lamps, goes significantly up to almost one hundred million won for 50 tonnage vessels and forty million won in case of vessels less than 10 tonnage. This cost has almost taken 40% of total fishing costs. That is, the fishing business condition of squid jigging fishery is recently in the very difficult situation. As oil price increases, the business condition of the fishery gets worse and worse. Therefore it is very urgent to develop an economical fishing lamp, to solve this problem of fishery's business difficulty. This research aims at developing a fishing lamp for squid jigging fishery using the light emitting diode which has very excellent efficiency and durability. We made a water tank with 20 meters width which is a shape of raceway to research behavioral characteristics of Japanese flying squid to LED light, and made an experiment to investigate optimum wave of LED light to lure squid. The method is to establish LED lamps on both ends of water tank and to observe squid's behavior. Colors and wave lengths of LED lamps, used in experiment, are red(634nm), yellow(596nm), green(523nm), blue(454nm) and white(454nm+560nm). In experiment for attractive capability of LED lamp to squids, Japanese flying squid are highly attracted to blue lamp and white lamp. However, they are dispersed to red and yellow lamps. In addition, Japanese flying squid have moved and stayed in both dark ends of water tank. When compared intermittent lamp with continuous lamp, Japanese flying squid are highly attracted to intermittent lamp when intermittent interval is 0.25 second.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.3
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• pp.187-194
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• 2012

This study surveyed the fishing efficiency for Japanese common squid based on improvements made to LED fishing lamps by utilizing the training ship of Gangwon Provincial College. The training ship, Haesong-ho (24 tons), was equipped with seventy-two 150W electric power LED fishing lamps (10.8kW), and their fishing efficiency and fuel consumption level were surveyed for a total of ten times during the period between June 15, 2009 and July 27, 2009. In addition, the training ship was equipped with seventy-one 300W electric power LED fishing lamps (21.3kW) and their fishing efficiency and fuel consumption level were surveyed for a total of five times during the period between January 17, 2010 and August 4, 2010. In order to compare the fishing efficiency of LED fishing lamps, the catch of another fishing vessel equipped with Metal Halide (MH) fishing lamps of 120kW for the same period and at the same fishing grounds. The fuel consumption levels during the fishing operation of Haesong-ho was about 1,047.7 liters which was approximately 19.9% of the total fuel consumption level of 5,262.6 liters, and the fuel consumption level per operation hour was on average 9.2 liters. The number of Japanese common squid caught by the LED fishing lamp-equipped fishing vessel ranged from 12 to 1,640 squid for each fishing trial and the average quantity was 652. The number of Japanese common squid caught by the MH fishing lamp-equipped 10 fishing vessels ranged from 40 to 4,800 squid and the average quantity was 2,055. The fishing of Japanese common squid was done by the use of hand lines and an automatic jigging machine. The number of Japanese common squid caught per hand line and a single roller of the automatic jigging machine was in the proportion of 50.8% to 49.2% with respect to the LED fishing lamp-equipped fishing vessel. However, the number of Japanese common squid caught per hand line and a single roller of the automatic jigging machine was in the proportion of 86.4% to 13.6% with respect to the MH fishing lamp-equipped fishing vessel where most of the catch was made by hand lines. On the other hand, in comparing the number of Japanese common squid caught per automatic jigging machine, the number of squid caught by the LED fishing lamp-equipped fishing vessel was about the same or greater than the number of squid caught by the MH fishing lamp-equipped fishing vessel.