Ding W, Würsig B, Leatherwood S
Marine Mammal Research Program, Texas A&M University at Galveston, 77551-5923, USA.
J Acoust Soc Am. 2001 Jan;109(1):407-11. doi: 10.1121/1.1326082.
Whistles were recorded and analyzed from free-ranging single or mixed species groups of boto and tucuxi in the Peruvian Amazon, with sonograms presented. Analysis revealed whistles recorded falling into two discrete groups: a low-frequency group with maximum frequency below 5 kHz, and a high-frequency group with maximum frequencies above 8 kHz and usually above 10 kHz. Whistles in the two groups differed significantly in all five measured variables (beginning frequency, end frequency, minimum frequency, maximum frequency, and duration). Comparisons with published details of whistles by other platanistoid river dolphins and by oceanic dolphins suggest that the low-frequency whistles were produced by boto, the high-frequency whistles by tucuxi. Tape recordings obtained on three occasions when only one species was present tentatively support this conclusion, but it is emphasized that this is based on few data.
在秘鲁亚马逊地区，对自由放养的单独或混合物种的亚河豚和土库河豚群体的口哨声进行了记录和分析，并展示了声谱图。分析发现记录到的口哨声分为两个不同的组：一个低频组，其最大频率低于5千赫兹；一个高频组，其最大频率高于8千赫兹，通常高于10千赫兹。两组口哨声在所有五个测量变量（起始频率、结束频率、最低频率、最高频率和持续时间）上都有显著差异。与其他淡水豚类和海洋豚类已发表的口哨声细节进行比较表明，低频口哨声是亚河豚发出的，高频口哨声是土库河豚发出的。在仅有一种物种出现的三次情况下获得的录音初步支持了这一结论，但需要强调的是，这是基于很少的数据得出的。
