Fish may safely graze

Good news for fish and one of the potential objections to turbines.

Infrasound are acoustic signals characterised by frequencies below 20 Hz, too low for human hearing. Infrasounds are natural alarm signals for fish, and the intensity used by the infrasound fish fence of Profish Technology create literally shake the fish, creating an uncomfortable area that they always avoid, with no habituation. Consequently, this system has revealed in the scientific literature the best efficiency results on the largest number of fish species, as observed during the test on the cooling water intake in Belgium where a reduction of 85% of the fish entrained was observed. An adequate location of the infrasound units will thus induce avoidance trajectories of fish.

ScienceDaily: Deep Sounds Scare Fish Away From Turbines That Could Kill Them

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