Meeting Abstract
Measuring fine-scale movement, performance, and energetics of large carnivores and their prey is critical for understanding the physiological underpinnings of trophic interactions. Yet our ability to describe the free-ranging dynamics between highly active carnivores is substantially impaired by the wide-ranging and cryptic behaviors of these large mammals. Advances in biologging sensor technology now make it possible to remotely quantify fine-scale movement patterns and energetics. Here we used calibrated SMART collars containing GPS and 3-axis accelerometers to monitor evasion and escape maneuvers and energetics during predator-prey chase sequences using trained scent hounds (Canis familiaris, avg. mass = 25.4 kg) pursuing pumas (Puma concolor, avg. mass = 60.3 kg) that were simultaneously instrumented. Reconstruction of chases reveals how pumas successfully used terrain (e.g., fleeing up steep, wooded hillsides) as well as evasive maneuvers (e.g., running in a figure-8 pattern) to increase their escape distance from the faster hounds (avg. 45% faster). These adaptive strategies were essential to successful escape in light of the 1.6-2.1x higher mass-specific energetic costs of the chase for pumas compared to hounds (avg. 1.08 vs. 0.593 kJ·kg-1·min-1, respectively). On average, escapes were exceptionally costly for pumas, requiring exercise at 89.7% of predicted VO2max and consuming 26% more energy than typically spent for hunting activity. These results demonstrate the marked investment of energy for escape by a large mammal and the advantage of dynamic maneuvers to aid in reducing total chase time.
