Exposure to a raptor‐like robot induces collective escape responses in two avian species and can trigger massive and persistent displacements

Bird flocks frequently generate human–wildlife conflicts, resulting in safety and health hazards, and economic losses. Remotely controlled, raptor-like robots have recently emerged as potentially effective deterrence tools, exploiting the innate collective escape response of birds to their predators and hence avoiding the emergence of habituation, but field tests are still scanty. We tested the effectiveness of a robotic falcon (RobotFalcon [RF]) as a deterrence tool for feral pigeons Columba livia breeding and feeding in a cattle farm (~500 individuals) and black-headed gulls Chroicocephalus ridibundus night-roosting in a wastewater treatment plant (~8000 individuals). We analysed collective behavioural responses during 10-min RF exposure trials mimicking natural predator attacks and assessed deterrence effectiveness (change in the number of birds) at different temporal scales (immediate response—within-trials and returning post-trials; short-term response—across 5–8 successive daily exposures). We also evaluated medium-term deterrence effectiveness by quantifying gull flight activity using a marine radar for ~10 days after RF exposure trials. The RF induced consistent collective behavioural responses, similar to real avian predators. The frequency of collective behaviours decreased both within- and across trials, mainly because flocks rapidly abandoned the target sites. Pigeons decreased both during and increasingly across trials, abandoning the target site soon after trial onset. However, most pigeons returned within 30 min after the end of trials, and individuals returning post-trials decreased only slightly (13%) across trials. The RF triggered massive gull displacements during trials, with a faster reaction in the last trial days compared to initial ones, and individuals returning post-trials decreased markedly (94%) across trials. Night flight activity showed a large (40%) decrease post- compared to pre-trial days, suggesting persistent deterrence effects. Practical implication. The RF is a valuable tool to deter birds from gathering in flocks in contexts where human–wildlife conflict may arise, based on robust evidence and field tests under different conditions. Yet, its effectiveness may depend on the importance of resources used by the target flocking species at the exposure site. Predator-like robots provide unique advantages related to animal welfare, consistency of deterrence protocols and effective management of human–wildlife conflicts.