Meeting Abstract

84.2  Tuesday, Jan. 6  Flight performance and aggression in jousting orchid bees: What determines success in competitive interactions? COMBES, S.A.*; PALEN, W.P.; Harvard University; Simon Fraser University scombes@oeb.harvard.edu

Many animals engage in competitive interactions to establish territories, gain access to resources, and attract mates. Locomotion is often central to these interactions, yet the relative importance of locomotory performance versus behavioral strategy is unknown. Male orchid bees perform aggressive aerial jousting matches over sources of aromatic oils, which the bees collect from plants and store in their hind legs for courtship. These jousting matches can include extended aerial maneuvering bouts, chases, and aerial collisions. We filmed wild, Panamanian orchid bees jousting over a fragrance source, and analyzed videos to determine the 3-dimensional movements of each bee during the interaction. We also categorized and recorded several distinct aggressive behaviors, and determined the proportion of time that bees spent engaged in various activities. We find that bees involved in aggressive interactions spend less time collecting fragrance, less time hovering, and more time engaged in fast, maneuvering flight. The time spent on these activities, as well as mean flight velocity, depends on the number of bees involved. Traditional measures of flight performance such as velocity and acceleration are not correlated with an individual bee’s success (time spent on the fragrance source), although other biomechanical traits such as collision stability may play a role. Overall aggressiveness does appear to be related to success in these encounters, but behavioral strategy varies depending on the number of interacting bees. These results highlight the importance of considering biomechanical performance in the context of the complex locomotory behaviors performed by wild animals.