Elephant habituation to drones as a behavioural observation tool

Unmanned Aerial Vehicles, known as UAVs or drones, are increasingly important as a tool in wildlife research and conservation. However, it is crucial to quantify as well as qualify the response of target species to drones. We measured the reaction of African savannah elephants (Loxodonta africana) to an off-the-shelf quadcopter drone during sequences of repeated trials. In total we conducted 35 trials involving 14 distinct and individually identified elephant groups, exposing them to the drone on up to four separate occasions. Half of trials recorded evidence of disturbed behaviour, but the proportion of disturbed elephants returned to levels comparable to pre-exposure by the end of the exposure period, suggesting some degree of habituation to drones over the course of a single trial. Additionally, repeated trials had significantly fewer instances of disturbed behaviour compared to initial trials, suggesting long-term habituation as well. Nonetheless, some small-scale changes in activity patterns were observed even after repeated trials. Our results suggest that elephants can habituate to drones, especially when they are flown according to guidelines which minimise disturbance. This indicates that drones can be used as a minimally invasive technology to monitor elephant behaviour provided that baseline activity patterns are recorded and quantified prior to drone exposure.