Underwater observation of puffer Lagoscephalus behavior to pot trap

In order to analyze the capturing mechanism of pot traps, fish behavior was observed in and around a trap using an underwater TV system. The behavior pattern was classified as follows: (1) appearing in the camera view, (2) swimming towards the entrance, (3) entering inside the funnel, (4) eating the bait, (5) going backward foward the funnel, (6) passing through the inner opening, (7) swimming out of the camera view. During the 1, 150 min of observed period, total numbers of appearances were 131 times, entering inside the funnel 57 times and capture 3 times, respectively. The puffer swan backward from the funnel by paddling the pectral fins foward the snout of the fish. The capturing mechanism of the fish trap seemed to be affected by the freedom of swimming behavior of puffer fish inside of the funnel.