A meta-analysis of the impact of drones on birds

Drones are increasingly being used to monitor, film, and survey birds. Many studies also report that, as compared to traditional methods such as ground counts or helicopter surveys, drones can reduce bird disturbance. Yet, best practices on how drones should be flown to reduce adverse behavior are usually species-specific and context-dependent, and are therefore often difficult to apply to new management scenarios. Here, we reviewed 149 avian studies, all of which involved drone use and were published in peer-reviewed scientific journals, and conducted a phylogenetically informed meta-analysis to better understand which factors can help to reduce flushing response in birds. The distance between the drone and the bird, drone speed, bird breeding status, and species size all strongly influenced the chances of a flushing response. Finally, we provide drone operational guidelines that are specific to and applicable across both drone type and taxa of interest.