Fang Liang, Li Songhai, Wang Kexiong, Wang Zhitao, Shi Wenjing, Wang Ding
The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.
Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Sanya Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, People's Republic of China.
J Acoust Soc Am. 2015 Sep;138(3):1346-52. doi: 10.1121/1.4929492.
While the low-frequency communication sounds of Indo-Pacific humpback dolphins (Sousa chinensis) have been reported in a number of papers, the high-frequency echolocation signals of Sousa chinensis, especially those living in the wild, have been less studied. In the current study, echolocation signals of humpback dolphins were recorded in Sanniang Bay, Guangxi Province, China, using a cross-type hydrophone array with five elements. In total, 77 candidate on-axis clicks from 77 scans were selected for analysis. The results showed that the varied peak-to-peak source levels ranged from 177.1 to 207.3 dB, with an average of 187.7 dB re: 1 μPa. The mean peak frequency was 109.0 kHz with a -3-dB bandwidth of 50.3 kHz and 95% energy duration of 22 μs. The -3-dB bandwidth was much broader than the root mean square bandwidth and exhibited a bimodal distribution. The center frequency exhibited a positive relationship with the peak-to-peak source level. The clicks of the wild Indo-Pacific humpback dolphins were short-duration, broadband, ultrasonic pulses, similar to those produced by other whistling dolphins of similar body size. However, the click source levels of the Indo-Pacific humpback dolphin appear to be lower than those of other whistling dolphins.
虽然已有多篇论文报道了印太驼背豚（中华白海豚，Sousa chinensis）的低频交流声音，但对中华白海豚高频回声定位信号的研究较少，尤其是对野生中华白海豚的高频回声定位信号研究更少。在本研究中，在中国广西三娘湾使用具有五个元件的交叉型水听器阵列记录了驼背豚的回声定位信号。总共从77次扫描中选择了77个候选轴向滴答声进行分析。结果表明，峰峰值源级变化范围为177.1至207.3 dB，平均为187.7 dB re: 1 μPa。平均峰值频率为109.0 kHz，-3 dB带宽为50.3 kHz，95%能量持续时间为22 μs。-3 dB带宽比均方根带宽宽得多，并且呈现双峰分布。中心频率与峰峰值源级呈正相关。野生印太驼背豚的滴答声是持续时间短、宽带的超声波脉冲，与其他体型相似的啸声海豚产生的滴答声相似。然而，印太驼背豚的滴答声源级似乎低于其他啸声海豚。
