Vergara Valeria, Mikus Marie-Ana, Chion Clément, Lagrois Dominic, Marcoux Marianne, Michaud Robert
Cetacean Conservation Research Program, Raincoast Conservation Foundation, PO Box 2429, Sidney, BC V8L 3Y3, Canada.
Département des Sciences Naturelles, Université du Québec en Outaouais, Ripon, QC J0V 1V0, Canada.
Biol Open. 2025 Mar 15;14(3). doi: 10.1242/bio.061783. Epub 2025 Mar 20.
Animal vocalizations can evolve structural features as long-term adaptations to noisy environments. Using such signals, cetaceans could mitigate masking from vessel noise. This study investigates whether beluga whales (Delphinapterus leucas) use ultrasonic high-frequency burst pulse (HFBP) calls to communicate in noisy conditions. We identified HFBP calls in three populations: St Lawrence Estuary, Eastern High Arctic-Baffin Bay, and Western Hudson Bay. Focusing on the industrialized St Lawrence, we investigated the effects of vessel noise on HFBP call rates compared to other call types. Ultrasonic calls, spanning a bandwidth of 36.4±6.5 to 144 kHz (Nyquist frequency), comprised 13% of the St Lawrence beluga repertoire (n=25,435). Noise events (n=21) were defined as periods when at least one vessel was visible within 2 km of the hydrophone while belugas were within 500 m. Sound pressure levels were measured before, during, and after exposure. Generalized linear mixed models revealed consistent HFBP call rates before, during, and after vessel noise exposure, while contact calls and other call types declined during exposure (n=4528). These findings suggest that ultrasonic signals that evolved in the Arctic - where ice-associated noise may have created a need for high-frequency communication - remain a viable communication channel in vessel noise, allowing belugas to exploit these signals to maintain communication. Understanding how belugas use signals in noisy environments can inform conservation strategies for noise-impacted marine mammals.
动物发声可以进化出结构特征，作为对嘈杂环境的长期适应。利用这些信号，鲸类动物可以减轻船只噪音的掩蔽效应。本研究调查了白鲸（白鲸属）是否使用超声波高频脉冲（HFBP）叫声在嘈杂环境中进行交流。我们在三个种群中识别出了HFBP叫声：圣劳伦斯河口、东高北极-巴芬湾和西哈德逊湾。聚焦于工业化程度较高的圣劳伦斯地区，我们调查了与其他叫声类型相比，船只噪音对HFBP叫声频率的影响。超声波叫声的带宽为36.4±6.5至144千赫（奈奎斯特频率），占圣劳伦斯白鲸全部叫声的13%（n=25435）。噪音事件（n=21）被定义为当至少有一艘船在水听器2公里范围内可见，而白鲸在500米范围内时的时间段。在暴露前、暴露期间和暴露后测量声压水平。广义线性混合模型显示，在船只噪音暴露前、暴露期间和暴露后，HFBP叫声频率保持一致，而接触叫声和其他叫声类型在暴露期间下降（n=4528）。这些发现表明，在北极进化而来的超声波信号——在那里与冰相关的噪音可能产生了对高频通信的需求——在船只噪音环境中仍然是一个可行的通信渠道，使白鲸能够利用这些信号来维持交流。了解白鲸在嘈杂环境中如何使用信号，可以为受噪音影响的海洋哺乳动物的保护策略提供信息。
