THRESHOLD OF THE JUVENILE ACIPENSER DABRYANUS DUMERIL

As an important “golden waterway” in China, the Yangtze River has suffered more and more destruction by human activities, such as ship transportation, channel improvement, bridge construction, hydraulic operations, dock loading and unloading, all of those caused noise pollution and influenced the fish lived in the river, even caused fish death. Acipenser dabryanus Dumeril as an important fish in the Yangtze River, its necessary to evaluate how the noise effects it. Based on this, in order to simulate the natural noise environment in the wild, the indoor noise control was used to this experiment, a stimulation frequency of 100—500 Hz was set, the Auditory Evoked Potential was used to test the threshold of juvenile Yangtze sturgeon (Acipenser dabryanus Dumeril). The results showed that the most sensitive frequency of the Acipenser dabryanus Dumeril is 300 Hz, the sound pressure is (133±0.5) dB, the hearing curve of Acipenser dabryanus Dumeril is a “V”-shaped. Different from other fishes, the Acipenser dabryanus Dumeril has a higher hearing threshold, but it cannot hear frequency above 500 Hz. Compared with the Acipenser fulvescens and Aspiolucius merzbacheri, the hearing thresholds between the three are similar. When compared with the common freshwater fish in the Yangtze River, the results showed that Acipenser dabryanus Dumeril has a higher threshold and narrower range of hearing frequency. Results of the experiment will provide important basic data for the protection and population reconstruction of the Acipenser dabryanus Dumeril, which also can provide basic data support for evaluating the impact of the fish-related projects of the fish lived in the Yangtze River.