Studying feral horse behavior from the sky

Unmanned aerial vehicles, commonly known as drones, have become widely available in recent years. A drone provides a bird’s eye view, which is useful in detecting and observing wild animals. One strength of imagery obtained by a drone is that it enables the capture of the two-dimensional spatial relationship of animals on the ground. I and colleagues have investigated the spatial relationships of feral horses at both intra- and inter-group levels. At the intra-group level, the distribution of the inter-individual distance of horses follows a certain pattern, indicating repulsion and attraction forces taking place among group members, similar to those in a school of fish, flock of birds, or swarm of insects. At the inter-group level, multiple unit groups aggregate to form a herd, suggesting the existence of a multilevel social structure. Automation of the analysis of the recordings of a drone, including target animal detection, individual identification, and motion tracking, presents a way forward. Drones and other emerging technologies will enhance our understanding of swarm behavior both in vivo and in vitro.