Assessing the Behavioural Responses of Small Cetaceans to Unmanned Aerial Vehicles

Unmanned Aerial Vehicles (UAVs), or drones, have recently emerged as a relatively affordable and accessible method for studying wildlife. Vertical Take-off Landing (VTOL) UAVs are appropriate morphometric, behavioural, abundance demographic studies of marine mammals, providing stable, nonintrusive highly manoeuvrable platform. Previous using VTOL been conducted on various mammal species, but specific regarding behavioural responses to these devices limited scarce. The aim this study was evaluate the immediate common (Delphinus delphis) bottlenose (Tursiops truncatus) dolphins UAV flown at different altitudes. A multirotor (quadcopter) with an attached GoPro camera used. Once dolphin group located, starting height 50 m directly above group, subsequently descending 5 every 30 s until reaching m. We assessed three heights: (i) direction changes, (ii) swimming speed (iii) diving. Responses by D. delphis (n = 15) T. truncatus 10) groups were analysed separately. There no significant any studied variables. For delphis, however, there statistically changes in when Our results indicate that do not induce heights > m, demonstrating use has minimal impact animals. However, we advise precautionary principle interpreting characteristics site (e.g., high whale-watching activity) may habituated anthropogenic disturbance.