What are the impacts of noise from wind turbines on birds, bats and other wildlife?
Areodynamic noise of large wind turbine ranges between 500 Hz and 1000 Hz with a range of 30 to 60 dBA and an average of 50 dBA intensity (loudness). Most of the sound of wind turbines blades is white noise, similar to wind blowing through tree leaves at a level of normal traffic noise. Therefore wind turbines are likely to affect bird song, hearing and behavior as if they were exposed to urban residential traffic noise. Research on birds’ ability to hear blades is still in its infancy, but preliminary results indicate that birds do not hear turbines as well as humans do (Dooling & Lohr 2000). This is less of a factor than with earlier-generation wind turbines, as technology has lowered noise levels to a range comparable with the decibel level of an office environment The very low frequencies, 4-16 Hz, (infrasound) transmitted through the ground could affect burrowing animals. Low frequency noises have been thought to be useful in bring earthworms to the surface and evicting moles. The
