Singing whales generate high levels of particle motion: implications for acoustic communication and hearing?

Acoustic signals are fundamental to animal communication, and cetaceans are often considered bioacoustic specialists. Nearly all studies of their acoustic communication focus on sound pressure measurements, overlooking the particle motion components of their communication signals. Here we characterized the levels of acoustic particle velocity (and pressure) of song produced by humpback whales. We demonstrate that whales generate acoustic fields that include significant particle velocity components that are detectable over relatively long distances sufficient to play a role in acoustic communication. We show that these signals attenuate predictably in a manner similar to pressure and that direct particle velocity measurements can provide bearings to singing whales. Whales could potentially use such information to determine the distance of signalling animals. Additionally, the vibratory nature of particle velocity may stimulate bone conduction, a hearing modality found in other low-freque...

声学信号是动物交流的核心基础，鲸类（cetaceans）常被视为生物声学（bioacoustic）领域的专精类群。当前针对鲸类声学交流的研究几乎全部聚焦于声压测量，却忽略了其交流信号中的质点运动（particle motion）分量。本研究对座头鲸鸣唱信号的声学质点速度（acoustic particle velocity）与声压水平进行了表征。研究证实，鲸类所产生的声场包含显著的质点运动分量，且该分量可在较远距离内被探测到，足以在声学交流中发挥作用。本研究发现，此类信号的衰减规律与声压信号具有可预测的相似性，且直接测量质点运动可确定鸣唱鲸类的方位。鲸类或可借助此类信息判断信号发送个体的距离。此外，质点速度的振动特性可能会刺激骨传导，这是其他低频率（low-freque，原文未完整展开）听觉类群所具备的一种听觉模态。