Data from: Terrestrial mammalian wildlife responses to Unmanned Aerial Systems approaches

Unmanned Aerial Systems (UAS) are increasingly being used recreationally, commercially and for wildlife research, but very few studies have quantified terrestrial mammalian reactions to UAS approaches. We used two Vertical Take-off and Landing (VTOL) UAS to approach seven herbivore species in the Moremi Game Reserve, Botswana, after securing the relevant permissions. We recorded responses to 103 vertical and 120 horizontal approaches, the latter from three altitudes above ground level (AGL). We ran mixed logistic regressions to identify factors triggering (i) any response and (ii) an evasive response. We included effects of activity, altitude, direction of approach, distance, habitat, herd type, herd size, other species, target species, time, VTOL type and wind strength. Response triggers were linked to altitude, distance, habitat and target species. Elephant (Loxodonta africana), giraffe (Giraffa camelopardalis), wildebeest (Connochaetes taurinus) and zebra (Equus quagga) were most affected by VTOL approach, impala (Aepyceros melampus) and lechwe (Kobus leche) were least responsive, and tsessebe (Damaliscus lunatus) displayed intermediate sensitivity. VTOLs flown lower than 60 m AGL and closer than 100 m horizontal distance from target animals triggered behavioural responses in most species. Enforced regulations on recreational UAS use in wildlife areas are necessary to minimise disturbance to terrestrial mammals.

无人航空系统（Unmanned Aerial Systems, UAS）正日益被应用于休闲娱乐、商业活动及野生动物研究领域，但目前仅有极少研究量化了陆地哺乳动物对无人航空系统近距离接近时的行为反应。本研究在获得相关实验许可后，于博茨瓦纳莫雷米动物保护区（Moremi Game Reserve）使用两款垂直起降（Vertical Take-off and Landing, VTOL）无人航空系统，对7种草食动物开展接近实验。研究共记录了103次垂直接近与120次水平接近场景，其中水平接近实验分别在三种离地高度（above ground level, AGL）下开展。我们采用混合逻辑回归模型，以识别两类关键触发因素：其一为引发动物产生任何形式反应的因素，其二为引发动物躲避行为的因素。模型纳入了活动状态、飞行高度、接近方向、距离、生境类型、种群类型、种群规模、共存物种、目标物种、观测时间、垂直起降机型以及风速等多项影响变量。分析结果显示，动物行为反应的触发因素与飞行高度、接近距离、生境类型及目标物种密切相关。其中，非洲象（Loxodonta africana）、长颈鹿（Giraffa camelopardalis）、斑纹角马（Connochaetes taurinus）与平原斑马（Equus quagga）对无人航空系统接近的反应最为强烈；黑斑羚（Aepyceros melampus）与驴羚（Kobus leche）的反应性最低，而转角牛羚（Damaliscus lunatus）则表现出中等程度的敏感性。当垂直起降机型离地高度低于60米AGL，且与目标动物的水平距离小于100米时，会触发多数受试物种产生行为反应。综上，为最大限度降低无人航空系统对陆地哺乳动物的干扰，有必要针对野生动物保护区内的休闲类无人航空系统使用制定强制监管规范。