Thompson P O, Findley L T, Vidal O
Departamento de Ciencias Marinas, Instituto Tecnológico y de Estudios Superiores de Monterrey, Guaymas, Sonora, México.
J Acoust Soc Am. 1992 Dec;92(6):3051-7. doi: 10.1121/1.404201.
Low-frequency vocalizations were recorded from fin whales, Balaenoptera physalus, in the Gulf of California, Mexico, during three cruises. In March 1985, recorded 20-Hz pulses were in sequences of regular 9-s interpulse intervals. In August 1987, nearly all were in sequences of doublets with alternating 5- and 18-s interpulse intervals. No 20-Hz pulse sequences of any kind were detected in February 1987. The typical pulse modulated from 42 to 20 Hz and its median duration was 0.7 s (1985 data). Most other fin whale sounds were also short tonal pulses averaging 82, 56, and 68 Hz, respectively, for the three cruises; 89% were modulated in frequency, mostly downward. Compared to Atlantic and Pacific Ocean regions, Gulf of California 20-Hz pulses were unique in terms of frequency modulation, interpulse sound levels, and temporal patterns. Fin whales in the Gulf may represent a regional stock revealed by their sound characteristics, a phenomenon previously shown for humpback whales, birds, and fish. Regional differences in fin whale sounds were found in comparisons of Atlantic and Pacific locations.
在三次航行期间，从墨西哥加利福尼亚湾的长须鲸（Balaenoptera physalus）身上记录到了低频发声。1985年3月，记录到的20赫兹脉冲以9秒的固定脉冲间隔序列出现。1987年8月，几乎所有脉冲都以双脉冲序列出现，脉冲间隔交替为5秒和18秒。1987年2月未检测到任何类型的20赫兹脉冲序列。典型脉冲从42赫兹调制到20赫兹，其持续时间中位数为0.7秒（1985年数据）。在这三次航行中，大多数其他长须鲸声音也是短音调脉冲，平均频率分别为82赫兹、56赫兹和68赫兹；89%的声音在频率上有调制，大多是向下调制。与大西洋和太平洋地区相比，加利福尼亚湾的20赫兹脉冲在频率调制、脉冲间隔声级和时间模式方面是独特的。加利福尼亚湾的长须鲸可能因其声音特征而代表一个区域种群，这种现象此前在座头鲸、鸟类和鱼类中也有发现。在对大西洋和太平洋地区长须鲸声音的比较中发现了区域差异。
