Meeting Abstract
Pursuit and interception of moving prey in a 3D environment is a challenging problem nevertheless solved in practice by predators in aquatic, terrestrial and aerial environments. However, the details and sophistication of tracking and intercept strategies little understood and may vary widely based on the biomechanical and sensory capabilities of the species in question. Here we examine aerial predator-prey interactions between barn swallows (Hirundo rustica) and insects recorded from wild, freely behaving birds as part of a larger study of swallow field flight behavior and biomechanics. The larger insects recorded here are large and likely not typical barn swallow prey species, but the swallows pursued, intercepted and in the majority of cases some insight may be gained from the results. The prey species in question were not identified but were fast moving, with mean ground speeds of 4.2 to 10.6 m/s; the birds flew at 9.9 m/s and faster. The swallows were foraging low to the ground and prey and swallows were at similar heights; swallows approached in the horizontal and slightly above. The intercept strategy likely varied within even the few available cases since they include a range of visual bearings, a potential constant bearing intercept and others with large changes in visual bearing through the approach. Swallow approaches ranged from behind the prey at a shallow intercept angle to a nearly 90 degree angle after circling from a position well in advance of the insect’s path. Response latencies, as determined by cross-correlation of centripetal force, were on the order of 1-2 swallow wingbeats.
