Funding information Office of Naval Research, Grant/Award Number: N00014-02-C-0180 Abstract Shore-based theodolite tracking of eastern gray whale (Eschrichtius robustus) movements was conducted to test for potential whale responses to a high-frequency sonar system. Southbound migrating whales were observed from two California shore observation stations as the whales swam past the source vessel that was moored in their migration path. The sonar transducer was deployed from the vessel during all observations, broadcasting 21–25 kHz sweeps for half of each day, the other half remaining silent. The order of control and experimental periods was randomized. No readily apparent response to sonar transmissions was observed in the field or in the visual data. Statistical analysis of tracking data indicates that, compared to control data, gray whales deflected inshore at ranges of 1–2 km from the vessel during sonar transmissions at a received sound pressure level of approximately 148 dB re 1 μPa (134 dB re 1 μPas). These data suggest that the functional hearing sensitivity of gray whales extends to at least 21 kHz.

中文翻译：

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灰鲸听到并响应来自 21–25 kHz 有源声纳的信号

资助信息 海军研究办公室，拨款/奖励编号：N00014-02-C-0180 摘要 对东部灰鲸（Eschrichtiusrobustus）运动进行岸基经纬仪跟踪，以测试鲸鱼对高频声纳系统的潜在反应。当鲸鱼游过停泊在其迁徙路径上的源船时，从两个加利福尼亚海岸观测站观察到南行迁徙的鲸鱼。在所有观测期间，声纳换能器从船上部署，每天有一半时间广播 21-25 kHz 扫描，另一半保持沉默。控制期和实验期的顺序是随机的。在现场或视觉数据中没有观察到对声纳传输的明显响应。跟踪数据的统计分析表明，与对照数据相比，在声纳传输期间，灰鲸在距离船只 1-2 公里的范围内偏转近海，接收到的声压级约为 148 dB re 1 μPa (134 dB re 1 μPas)。这些数据表明，灰鲸的功能性听觉灵敏度至少可扩展到 21 kHz。