Can experience reduce collisions between birds and vehicles?

Abstract

Bird collisions with vehicles cause serious safety, financial and conservation concerns worldwide, but the causes of such collisions are poorly described. We investigated how experience with vehicles influenced avian avoidance responses. We trained three groups of vehicle-naïve rock pigeons Columba livia with 32 near-miss vehicle approaches over 4 weeks at 60 and 120 km h−1, and also included individuals that heard but did not see the approaches (control group). We subsequently measured flight initiation distance (FID) and whether individuals ‘collided’ with a virtual vehicle directly approaching at 120 or 240 km h−1 using video playback. We found that inexperienced individuals (i.e. the control group) had longer FIDs than experienced birds, although only one of 90 individuals across groups successfully avoided virtual collision. Vehicle approach speed during video playback and the interaction of approach speed and training group did not influence FID. Our results suggest that a habituation-like effect based on repeated observations of passing vehicles could contribute to ineffective vehicle avoidance responses by birds when collisions are imminent. Novel strategies should be developed to enhance avoidance responses to high-speed vehicles to minimize bird mortality.