Meeting Abstract
Dragonflies are highly successful aerial predators that pursue a variety of prey, engaging in complex, three-dimensional pursuits that are typically completed in less than a second. Because mechanistic studies of aerial predation are scarce, we do not yet know whether predators employ a general kinematic and behavioral strategy when pursuing most prey, or whether they tailor their pursuit to each prey type; nor do we know how widely prey species differ in their survival strategies and in their sensorimotor capabilities. To address these questions, we examined aerial interactions between dragonflies and dipteran prey, filming hundreds of encounters with high-speed video to reconstruct 3-d trajectories, quantify flight biomechanics, and examine pursuit and escape strategies. We studied three species of libellulid dragonflies (Libellula cyanea, Pachydiplax longipennis, and Sympetrum rubicundulum) pursuing four species of dipteran prey. By analyzing large numbers of encounters between different predator-prey pairs, we were able to identify common mechanical features of dragonfly predation, infer which prey species can sense and actively respond to approaching predators, and pinpoint key factors that help determine the outcome of predator-prey interactions. Surprisingly, we found that two of the dragonfly species achieve similar levels of capture success and expend similar amounts of power to capture prey, but they do so using very different capture strategies: slow, stealthy approaches that prey rarely detect vs. rapid, powerful approaches that prey try to evade but rarely can. These findings highlight the importance of examining complex flight behaviors such as predator-prey interactions in a natural, comparative context.
