Study on the Behavioral Reactions of Fish to the Acoustic Sound―I Behavioral Reactions of a Guppy to the Pure Tones in Case of a Individual Body

The fundamental experiment was carried out to study the behavioral reactions of fish to the acoustic stimuli for the purpose of utilitarian improvement of the fishing gears and methods. The experiment was carried out in the experimental water tank in which the observation area was limited by the frame (50×50×10 cm). The guppy, Lebistes reticulata, was employed for the experimental object. As for the acoustic stimulus, the pure tones of the sine wave were used at each step of the frequency of 150, 200, 250, 300, 400, 500, 600, 700, and 800Hz. Each sound was emitted not only continuously but also intermittenly, and moreover the behavior of fish with no stimulus was observed for the sake of comparison. It was obtained that the behavioral reactions of the guppy were restrained under the condition of stimuli except 500Hz. The degree of restriction under the reciprocal sound was bigger than that of the continuous ones, especially it was remarkable in case of 400Hz. Although the behavioral reactions of the fish seemed to be at random, it was found that there was a main behavioral period of about 100 sec. and also the behavioral period and pattern were not influenced by the sound stimuli