Squid jigging fisheries in Japan using fishing lights require large amounts of electric power. To improve energy efficiency, the methodology of this fisheries should be reconstructed through understanding capture processes, but most of capture process of squid jigging remain unknown. In this study, the capture process of this fisheries was discussed based on behavioral experiments and observations of fishing lights by underwater camera. Results of behavioral experiments indicate that squid responded to the light direction rather than the light intensity. They oriented to light from a horizontal direction, moved toward the light source and remained in the environment where light was coming from above them. Underwater observations showed that far from the boat, the light from fishing lamps reached the camera from a horizontal direction, while nearby the boat, the light reached the camera almost vertically. From these results, it is considered that the fishing lights of squid jigging boats have two functions. The first is to lead squid toward the boat from a wide area, and the second is to retain the squid under the boat. When improving the fishing light system, arrangement of light source should be planned so as not to impair these functions.
