Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, Solomons, MD, United States of America.
PLoS One. 2024 Apr 18;19(4):e0299250. doi: 10.1371/journal.pone.0299250. eCollection 2024.
Passive acoustic monitoring has improved our understanding of vocalizing organisms in remote habitats and during all weather conditions. Many vocally active species are highly mobile, and their populations overlap. However, distinct vocalizations allow the tracking and discrimination of individuals or populations. Using signature whistles, the individually distinct calls of bottlenose dolphins, we calculated a minimum abundance of individuals, characterized and compared signature whistles from five locations, and determined reoccurrences of individuals throughout the Mid-Atlantic Bight and Chesapeake Bay, USA. We identified 1,888 signature whistles in which the duration, number of extrema, start, end, and minimum frequencies of signature whistles varied significantly by site. All characteristics of signature whistles were deemed important for determining from which site the whistle originated and due to the distinct signature whistle characteristics and lack of spatial mixing of the dolphins detected at the Offshore site, we suspect that these dolphins are of a different population than those at the Coastal and Bay sites. Signature whistles were also found to be shorter when sound levels were higher. Using only the passively recorded vocalizations of this marine top predator, we obtained information about its population and how it is affected by ambient sound levels, which will increase as offshore wind energy is developed. In this rapidly developing area, these calls offer critical management insights for this protected species.
被动声学监测提高了我们对远程栖息地和各种天气条件下发声生物的理解。许多发声活跃的物种具有高度的流动性，其种群重叠。然而，独特的叫声可以用于追踪和区分个体或种群。通过使用特征口哨声，即宽吻海豚个体独特的叫声，我们计算了个体的最小丰度，对来自五个地点的特征口哨声进行了特征描述和比较，并确定了个体在美国大西洋中部和切萨皮克湾的重现率。我们鉴定了 1888 个特征口哨声，其中口哨声的持续时间、极值数量、起始、结束和最小频率在不同地点显著不同。特征口哨声的所有特征都被认为对于确定口哨声的来源非常重要，而且由于近海地点检测到的海豚具有独特的特征口哨声特征且没有空间混合，我们怀疑这些海豚与沿海和海湾地点的海豚来自不同的种群。当声音水平较高时，特征口哨声也会变短。仅使用这种海洋顶级捕食者的被动记录发声，我们就获得了有关其种群的信息，以及其如何受到环境声音水平的影响，随着海上风能的发展，环境声音水平将会增加。在这个快速发展的地区，这些叫声为这种受保护物种的管理提供了关键的见解。
