Philips Jennifer D, Nachtigall Paul E, Au Whitlow W L, Pawloski Jeffrey L, Roitblat Herbert L
Marine Mammal Research Program, Hawaii Institute of Marine Biology, P.O. Box 1106, Kailua, Hawaii 96734, USA.
J Acoust Soc Am. 2003 Jan;113(1):605-16. doi: 10.1121/1.1527964.
The Risso's dolphin (Grampus griseus) is an exclusively cephalopod-consuming delphinid with a distinctive vertical indentation along its forehead. To investigate whether or not the species echolocates, a female Risso's dolphin was trained to discriminate an aluminum cylinder from a nylon sphere (experiment 1) or an aluminum sphere (experiment 2) while wearing eyecups and free swimming in an open-water pen in Kaneohe Bay, Hawaii. The dolphin completed the task with little difficulty despite being blindfolded. Clicks emitted by the dolphin were acquired at average amplitudes of 192.6 dB re 1 microPa, with estimated sources levels up to 216 dB re 1 microPa-1 m. Clicks were acquired with peak frequencies as high as 104.7 kHz (Mf(p) = 47.9 kHz), center frequencies as high as 85.7 kHz (Mf(0) = 56.5 kHz), 3-dB bandwidths up to 94.1 kHz (M(BW) = 39.7 kHz), and root-mean-square bandwidths up to 32.8 kHz (M(RMS) = 23.3 kHz). Click durations were between 40 and 70 micros. The data establish that the Risso's dolphin echolocates, and that, aside from slightly lower amplitudes and frequencies, the clicks emitted by the dolphin were similar to those emitted by other echolocating odontocetes. The particular acoustic and behavioral findings in the study are discussed with respect to the possible direction of the sonar transmission beam of the species.
里氏海豚（Grampus griseus）是一种专门以头足类动物为食的海豚科动物，其前额有明显的垂直凹痕。为了研究该物种是否使用回声定位，一只雌性里氏海豚在佩戴眼罩并在夏威夷卡内奥赫湾的一个开放式水域围栏中自由游动时，接受训练以区分铝制圆柱体和尼龙球体（实验1）或铝制球体（实验2）。尽管被蒙上眼睛，这只海豚完成任务几乎没有困难。海豚发出的咔哒声平均振幅为192.6分贝（相对于1微帕），估计声源级高达216分贝（相对于1微帕 - 1米）。采集到的咔哒声峰值频率高达104.7千赫兹（Mf(p) = 47.9千赫兹），中心频率高达85.7千赫兹（Mf(0) = 56.5千赫兹），3分贝带宽高达94.1千赫兹（M(BW) = 39.7千赫兹），均方根带宽高达32.8千赫兹（M(RMS) = 23.3千赫兹）。咔哒声持续时间在40到70微秒之间。这些数据表明里氏海豚会使用回声定位，并且除了振幅和频率略低之外，该海豚发出的咔哒声与其他使用回声定位的齿鲸发出的咔哒声相似。研究中具体的声学和行为学发现将根据该物种声纳传输波束的可能方向进行讨论。
