Catching efficiency of LED fishing lamp and behavioral reaction of common squid Todarodes pacificus to the shadow section of color LED light

Abstract

This study made a comparative analysis of behavioral reaction of squid to red (624 nm ), green (524 nm ), blue (460 nm ) & 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 (0.05 lx ) condition . Under the brighter condition than 0.05 lx , 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