Study on behavior of sound stimulation for large yellow croaker (Pseudosciaena crocea)

An experiment of hearing sensitive test for 3 different ages of large yellow croaker( Pseudosciaenacrocea) was carried out for behavioral observation to understand the impact of injury levels by underwater strong noise. The results showed that all 3 age fish generated condition response when the underwater sound pressure reached approximately 10 Pa. However,their hearing threshold and acoustic sensitive frequency were significantly different. The hearing thresholds of direct mortality for 1-month seedling and 8-month fish were 40 Pa and 4 kPa respectively. Similarly,the acoustic sensitive frequencies were 800 Hz and 600 Hz. For 13-month fish,despite its acoustic sensitive frequency at 600 Hz,no direct mortalities but significantly frightened were found when the sound pressure climbed to 4 kPa. Additionally,the fishes exposed by strong sound pulses in the experiment tend to die-offs in 48 hours. The analysis show that the fishes exposure long to underwater sound pulses may have cause cumulative effects of behavior pattern change and indirect chronic hazards when noise persisted.