Ewing Jack P, Hidalgo-Pla Eva, Solsona-Berga Alba, Frasier Kaitlin E, Ootoowak Alex J, Westdal Kristin H, Wiggins Sean M, Hildebrand John A, Jones Joshua M
Scripps Institution of Oceanography, University of California San Diego, La Jolla, 92093, USA.
Oceans North, Ottawa, K2P 1R2, Canada.
Sci Rep. 2025 Jul 2;15(1):23126. doi: 10.1038/s41598-025-04032-1.
The Arctic Ocean is undergoing rapid sea ice loss and increasing ship traffic, introducing potential stressors for wildlife and challenges for management and conservation. This study examines narwhal (Monodon monoceros) responses to vessels in eastern Eclipse Sound, Nunavut, Canada using underwater acoustic recordings and ship tracking data collected between 2016 and 2021. The effect of ship proximity on detection of narwhal echolocation clicks was analyzed, accounting for environmental and temporal factors affecting detection probability. Narwhal acoustic presence exhibits seasonality, peaking in July and October, and is correlated with low solar angle in both seasons and sea ice concentration during ice formation in October. Our analysis revealed an inverse relationship between ship proximity and narwhal acoustic presence in July and October, most pronounced when ships were within 20 km of the recorder in October. These distances suggest that narwhals react to broadband sound pressure levels well below 120 dB re: 1 µPa and are more sensitive to low-frequency sounds (< 1 kHz) than previously assumed. This study offers region- and population-specific insights into narwhal responses to ships, highlighting the importance of integrating long-term monitoring of wildlife, environmental conditions, and human activities to improve prediction of Arctic marine species' movements and behavior.
北冰洋正在经历快速的海冰流失和船舶交通量增加，这给野生动物带来了潜在压力源，也给管理和保护工作带来了挑战。本研究利用2016年至2021年期间收集的水下声学记录和船舶跟踪数据，研究了加拿大努纳武特地区伊克利斯湾东部独角鲸（Monodon monoceros）对船只的反应。分析了船舶接近度对独角鲸回声定位咔哒声检测的影响，并考虑了影响检测概率的环境和时间因素。独角鲸的声学出现具有季节性，在7月和10月达到峰值，并且在这两个季节与低太阳角度以及10月冰层形成期间的海冰浓度相关。我们的分析揭示了7月和10月船舶接近度与独角鲸声学出现之间的反比关系，10月当船舶距离记录仪在20公里以内时最为明显。这些距离表明，独角鲸对远低于120分贝（相对于1微帕）的宽带声压水平有反应，并且比之前假设的对低频声音（<1千赫）更敏感。本研究提供了针对独角鲸对船舶反应的特定区域和种群的见解，强调了整合对野生动物、环境条件和人类活动的长期监测以改善对北极海洋物种移动和行为预测的重要性。
