Jones Benjamin A, Stanton Timothy K, Lavery Andone C, Johnson Mark P, Madsen Peter T, Tyack Peter L
Department of Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543-1053, USA.
J Acoust Soc Am. 2008 Mar;123(3):1753-62. doi: 10.1121/1.2828210.
Blainville's beaked whales (Mesoplodon densirostris) use broadband, ultrasonic echolocation signals with a -10 dB bandwidth from 26 to 51 kHz to search for, localize, and approach prey that generally consist of mid-water and deep-water fishes and squid. Although it is well known that the spectral characteristics of broadband echoes from marine organisms vary as a function of size, shape, orientation, and anatomical group, there is little evidence as to whether or not free-ranging toothed whales use spectral cues in discriminating between prey and nonprey. In order to study the prey-classification process, a stereo acoustic tag was deployed on a Blainville's beaked whale so that emitted clicks and the corresponding echoes from targets in the water could be recorded. A comparison of echoes from targets apparently selected by the whale and those from a sample of scatterers that were not selected suggests that spectral features of the echoes, target strengths, or both may have been used by the whale to discriminate between echoes. Specifically, the whale appears to favor targets with one or more nulls in the echo spectra and to seek prey with higher target strengths at deeper depths.
布兰氏喙鲸（Mesoplodon densirostris）使用带宽为-10分贝、频率范围在26至51千赫的宽带超声波回声定位信号来搜索、定位并接近猎物，这些猎物通常包括中水层和深水层的鱼类及鱿鱼。尽管众所周知，海洋生物的宽带回波的频谱特征会因大小、形状、方向和解剖学类别而有所不同，但几乎没有证据表明自由游动的齿鲸在区分猎物和非猎物时是否会利用频谱线索。为了研究猎物分类过程，在一头布兰氏喙鲸身上部署了一个立体声学标签，以便记录发出的咔哒声以及水中目标的相应回波。对鲸鱼明显选择的目标的回波与未被选择的散射体样本的回波进行比较表明，鲸鱼可能利用了回波的频谱特征、目标强度或两者来区分回波。具体而言，鲸鱼似乎更喜欢回波频谱中有一个或多个零点的目标，并在更深的深度寻找具有更高目标强度的猎物。
