Determination of optimal flight altitude to minimise acoustic drone disturbance to wildlife using species audiograms
Determination of optimal flight altitude to minimise acoustic drone disturbance to wildlife using species audiograms
复制标题
DOI：
10.1111/2041-210x.13691
复制
发表时间：
2021-08-18
影响因子：
6.6
通讯作者：
Klinck, Holger
中科院分区：
文献类型：
--
作者：
Duporge, Isla;Spiegel, Marcus P.;Klinck, Holger
无人机（UAV）在野生动物数据收集方面越来越重要，但对野生动物干扰的担忧导致一些国家禁止在国家公园使用无人机。干扰是一个动物福利问题，并通过引发异常行为阻碍科学数据收集。处理干扰问题将使野生动物研究人员能够更有效和更道德地使用无人机技术。在这里，我们提出了一种新的方法来确定最佳的飞行高度，最大限度地减少无人机干扰野生动物使用物种听力图。我们记录了7个常见的无人机系统在水平和垂直平面上的声音剖面，增量为5米，最高可达120米。为了了解哺乳动物如何感知无人机的声音，我们使用了20个物种的听力图来计算每个物种在测量距离内每个无人机的响度。这些计算基于物种在相关频谱上的听觉灵敏度来过滤UAV噪声。我们设计了一种方法来优化图像空间分辨率和飞行高度之间的权衡。我们计算了无人机声级降低到可接受阈值以下的最低点，此处选择为40 dB，根据物种的听觉灵敏度进行加权，或者通过飞得更高而不能显著地进一步最小化干扰。后者被量化为一个点，在该点之上，每增加5米的飞行高度导致声压级平均下降小于0.05 dB。关于适当飞行高度的可靠数据可以指导关于无人机在野生动物上空飞行的政策规定，从而能够更多地将这一技术用于科学数据收集和野生动物保护目的。该方法很容易适用于其他物种和无人机系统的录音和听力图。
Unmanned aerial vehicles (UAVs) are increasingly important in wildlife data collection but concern over wildlife disturbance has led several countries to ban their use in National Parks. Disturbance is an animal welfare concern and impedes scientific data collection through provoking aberrant behaviour. Dealing with the issue of disturbance will enable wildlife researchers to use UAV technology more effectively and ethically. Here we present a novel method to determine optimal flight altitude for minimising drone disturbance for wildlife using species audiograms. We recorded sound profiles of seven common UAV systems in the horizontal and vertical planes at 5-m increments up to 120 m. To understand how mammals perceive UAV sound, we used audiograms of 20 species to calculate the loudness of each UAV for each species across the measured distances. These calculations filter the UAV noise based on the sensitivity of species' hearing over the relevant frequency spectrum. We have devised a method to optimise the trade-off between image spatial resolution and flight altitude. We calculated the lowest point at which either the UAV sound level decreases below an acceptable threshold, here chosen as 40 dB, weighted according to species' hearing sensitivity, or disturbance cannot be significantly further minimised by flying higher. The latter is quantified as the point above which each additional 5 m of flight altitude causes on average less than 0.05 dB decrease in sound pressure level. Reliable data on appropriate flight altitudes can guide policy regulations on flying UAVs over wildlife, thus enabling increased use of this technology for scientific data collection and for wildlife conservation purposes. The methodology is readily applicable to other species and UAV systems for which sound recordings and audiograms are available.