The attraction effect of natural feeding sound in fish

Many stimuli attracting fish are containing the characters of feeding sound emitted by the same species and the imitation sounds using for attracting fish make use of some characters of it. Using carp and yellow tail, the significant factors for attraction were investigated. These feeding sounds were consisted of a train of pulses having wide frequency components. Natural feeding sound projected into water was the best stimulus. The narrower frequency character made, the weaker effect became. But, as far as it contains time character of feeding sound, the attraction effect did not become null. On the other hand, artificial sound being used now at marine ranch showed threat effect for unlearned fish. The attraction effect depends on not only time character but also frequency component