Influence of rotation speed and frequency on the decision of Columba livia domestica (homing pigeon) to cross the rotor-swept area of paper blades mimicking a wind turbine.

This article investigates how blade rotational speed and frequency of wind turbine-like blades affect the flight decisions and collision risk of Columba livia domestica (domestic rock doves, aka homing pigeons). Using an experimental setup with rotating paper blades mimicking wind turbine rotors, the study found that pigeons were less likely to cross the rotor-swept area as blade speed and frequency increased, but collisions still occurred frequently (63% of crossing attempts resulted in collisions), regardless of blade speed or frequency. Pigeons often made avoidance decisions late, near the rotor, and previous collisions influenced their flight path but not their decision to cross. The findings suggest that slowing turbine blades to low rotational speeds, as done by automatic detection systems (ADS) intended to reduce bird collisions, may not effectively prevent collisions for some species, indicating that complete turbine shutdowns might be necessary, though the feasibility and economic costs of such measures require further study.