Department of Animal Biology, Edaphology and Geology, University of La Laguna, BIOECOMAC, Tenerife, Spain.
Department of Biology, Aarhus University, Zoophysiology, Aarhus, Denmark.
Sci Rep. 2021 Nov 11;11(1):21195. doi: 10.1038/s41598-021-00487-0.
Vessel noise is a primary driver of behavioural disturbance in cetaceans, which are targeted during whale-watch activities. Despite the growing, global effort for implementing best-practice principles, to date, there are no regulations on whale-watch vessel noise levels. Here, we test the hypothesis that a whale-watch vessel with a low noise emission will not elicit short-term behavioural responses in toothed whales compared to a vessel with a louder engine. We measured behavioural responses (n = 36) of short-finned pilot whales (Globicephala macrorhynchus) to whale-watch vessel approaches (range 60 m, speed 1.5 kn). Treatment approaches with a quieter electric engine (136-140 dB) compared to the same vessel with a louder petrol engine (151-139 dB) (low-frequency-mid-frequency weighted source levels, re 1 µPa RMS @ 1 m) were examined. Focal whales were resting mother and calves in small group sizes. During petrol engine treatments, the mother's mean resting time decreased by 29% compared to the control (GLM, p = 0.009). The mean proportion of time nursing for the calf was significantly influenced by petrol engine vessel passes, with a 81% decrease compared to the control (GLM, p = 0.01). There were no significant effects on behaviour from the quieter electric engine. Thus, to minimise disturbance on the activity budget of pilot whales, whale-watch vessels would ideally have source levels as low as possible, below 150 dB re 1 µPa RMS @ 1 m and perceived above ambient noise.
船只噪音是鲸类动物行为干扰的主要驱动因素，在观鲸活动中，它们是目标。尽管实施最佳实践原则的全球努力不断增加，但迄今为止，观鲸船只噪音水平尚无规定。在这里，我们检验了一个假设，即与噪音更大的发动机相比，低排放的观鲸船不会引起齿鲸的短期行为反应。我们测量了短鳍领航鲸（Globicephala macrorhynchus）对观鲸船接近（范围 60 米，速度 1.5 节）的行为反应（n=36）。与同一艘噪音更大的汽油发动机船（151-139 dB）相比， quieter 电动发动机（136-140 dB）的处理方法（低频中频加权声源级，re 1 µPa RMS @ 1 m）进行了检查。聚焦鲸鱼是在小群体中休息的母鲸和幼鲸。在汽油发动机处理期间，与对照相比，母鲸的平均休息时间减少了 29％（GLM，p=0.009）。幼鲸的平均哺乳时间受到汽油发动机船只通过的显著影响，与对照相比减少了 81％（GLM，p=0.01）。 quieter 电动发动机对行为没有明显影响。因此，为了尽量减少对领航鲸活动预算的干扰，观鲸船的理想声源级应尽可能低，低于 150 dB re 1 µPa RMS @ 1 m，且高于环境噪声。
