The aerial combat strategy of dragonflies.

Abstract

Male dragonflies engage in aggressive aerial contests to establish breeding territories. Using field stereographic recordings of Trithemis aurora, we examined dragonfly behavioural objectives during these encounters. Unlike predatory pursuits, in which intercept trajectories minimize time-to-contact, male T. aurora steer to keep their opponent in a slightly elevated position within their frontal visual field, modulating speed to avoid direct collision. These contests feature frequent role reversals, with evenly matched rivals alternating between chaser and evader. The manoeuvres observed during these exchanges, including looping and spiralling flight, emerge from the underlying pursuit objectives. During territorial conflicts, males exhibit exceptional agility with centripetal accelerations up to 6g. Despite this high performance, individuals spent approximately one-third of flight time gliding in short bursts, even during close combat. These findings show that complex aerial contests can arise from simple control objectives constrained by sensorimotor limits.