THRESHOLDS FOR THE HEARING OF MARBLED ROCKFISH SEBASTICUS MARMORATUS

The thresholds for the hearing of marbled rockfish (Sebasticus marmoratus) were studied using the auditory evoked potential (AEP) technique. The AEP responses to seven different sonic stimulations, whose tone burst frequencies are between 100—1000 Hz, from eight fishes were recorded by two subcutaneous electrodes (Tucker Davis Technologies). Our results showed that marbled rockfish were sensitive to the low frequency sounds ranging from 100 to 300 Hz, and the most sensitive sound frequency is 150 Hz, corresponding to the lowest hearing threshold of 70 dB re 1 μPa. The dominant frequency of the fish sound matches with their sensitive sound frequency range, which indicates that marbled rockfish are able to detect their own sounds, and the importance of acoustic communication among them. Meanwhile, low-frequency anthropogenic noise may affect their acoustic communication.