波弗特海浅水区中弓头鲸迁徙叫声的声源层级和调用深度分布

Source level and calling depth distributions of migrating bowhead whale calls in the shallow Beaufort Sea.

作者信息

Thode Aaron M, Blackwell Susanna B, Seger Kerri D, Conrad Alex S, Kim Katherine H, Michael Macrander A

机构信息

Marine Physical Laboratory, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0238, USA.

Greeneridge Sciences, Incorporated, 90 Arnold Place, Suite D, Santa Barbara, California 93117, USA.

出版信息

J Acoust Soc Am. 2016 Dec;140(6):4288. doi: 10.1121/1.4968853.

DOI:10.1121/1.4968853

PMID:28040014

Abstract

Automated and manual acoustic localizations of migrating bowhead whales were used to estimate source level and calling depth distributions of their frequency-modulated-modulated calls over seven years between 2008 and 2014. Whale positions were initially triangulated using directional autonomous seafloor acoustic recorders, deployed between 25 and 55 m water depth near Kaktovik, Alaska, during the fall westward migration. Calling depths were estimated by minimizing the "discrepancy" between source level estimates from at least three recorders detecting the same call. Applying a detailed waveguide propagation model to the data yielded broadband source levels of 161 ± 9 dB re 1 μPa s at 1 m (SEL) for calls received between 20 and 170 Hz. Applying a simpler 15 log(R) power-law propagation model yielded SEL source levels of 158 ± 10 dB. The most probable calling depths lay between 22 and 30 m: optimal depths for long-range acoustic signal transmission in this particular environment.

摘要

在2008年至2014年的七年时间里，利用自动和手动声学定位方法对迁徙的弓头鲸进行定位，以估计其调频调制叫声的声源级和发声深度分布。在秋季向西迁徙期间，鲸的位置最初是使用定向自主海底声学记录仪进行三角测量的，这些记录仪部署在阿拉斯加卡克托维克附近水深25至55米的地方。通过最小化至少三个检测到相同叫声的记录仪的声源级估计之间的“差异”来估计发声深度。将详细的波导传播模型应用于数据，得出在20至170赫兹之间接收到的叫声在1米处的宽带声源级为161±9分贝（相对于1微帕秒，声能级）。应用更简单的15log(R)幂律传播模型得出的声能级声源级为158±10分贝。最可能的发声深度在22至30米之间：这是在该特定环境中进行长距离声学信号传输的最佳深度。