Data from: Anthropogenic noise impairs cooperation in bottlenose dolphins

Understanding the impact of human disturbance on wildlife populations is
of societal importance, with anthropogenic noise known to impact a range
of taxa, including mammals, birds, fish, and invertebrates. While animals
are known to use acoustic and other behavioural mechanisms to compensate
for increasing noise at the individual level, our understanding of how
noise impacts social animals working together remains limited. Here, we
investigated the effect of noise on coordination between two bottlenose
dolphins performing a cooperative task. We previously demonstrated that
the dolphin dyad can use whistles to coordinate their
behaviour, working together with extreme precision. By equipping
each dolphin with a sound-and-movement recording tag (DTAG-3) and exposing
them to increasing levels of anthropogenic noise, we show that both
dolphins nearly doubled their whistle durations and increased whistle
amplitude in response to increasing noise. While these acoustic
compensatory mechanisms are the same as those frequently used by wild
cetaceans, they were insufficient to overcome the effect of noise on
behavioural coordination. Indeed, cooperative task success decreased in
the presence of noise, dropping from 85% during ambient noise control
trials to 62.5% during the highest noise exposure. To our knowledge, this
is the first study to demonstrate in any non-human species that noise
impairs communication between conspecifics performing a cooperative task.
Cooperation facilitates vital functions across many taxa and our findings
highlight the need to account for the impact of disturbance on
functionally important group tasks in wild animal populations.

探究人类活动干扰对野生动物种群的影响具有重要社会意义，已知人为噪声（anthropogenic noise）会对包括哺乳类、鸟类、鱼类以及无脊椎动物在内的诸多类群（taxa）造成影响。尽管已知动物会借助声学及其他行为机制在个体层面抵消噪声加剧带来的影响，但我们对于噪声如何影响协同协作的群居动物的认知仍十分有限。本研究针对开展协作任务的两只宽吻海豚之间的协调行为受噪声影响的情况展开探究。此前我们已证实，该海豚配对可借助哨声协调彼此行为，实现极高精度的协同配合。通过为每只海豚佩戴声音与运动记录标签（DTAG-3），并让它们暴露于强度逐步升高的人为噪声环境中，我们发现两只海豚均将哨声时长提升近一倍，且随噪声强度升高同步增大哨声振幅。尽管这类声学补偿机制与野生鲸类常用的补偿策略一致，但它们仍不足以抵消噪声对行为协调造成的干扰。确实，协作任务的完成率随噪声出现而下降，从背景噪声对照试验中的85%降至最高噪声暴露组的62.5%。据我们所知，本研究是首个在非人类物种中证实噪声会损害执行协作任务的同种个体间交流的研究。协同协作支撑着诸多类群的关键生命功能，本研究结果凸显了在野生动物种群中，需纳入考量干扰对具有功能重要性的群体任务的影响这一必要性。