Meeting Abstract
Arboreal birds frequently hop and fly among tree branches to search for food. In the process, they must maneuver around intervening leaves or branches that obstruct flight paths between reliable perches. To understand the tradeoffs in time, effort, and safety made during these flights, we studied voluntary, perch-to-perch flights made by Pacific parrotlets (Forpus coelestis) in a novel aerodynamic force platform. This setup enables direct, in vivo measurements of the vertical and horizontal aerodynamic forces produced by the birds during flight. To study how birds adapt their flight path when an obstacle is present, we compare the aerodynamics and high-speed kinematics of flights made with and without a horizontal string obstructing the path between two instrumented perches. These measurements are used to develop a new model for assessing the implications of their flight strategies on time and energetic cost. The model can be further generalized to analyze locomotion strategies employed by other animals or improve bimodal robots traversing cluttered environments.
