Behavioural reactions of cod (Gadus morhua) and plaice (Pleuronectes platessa) to sound resembling offshore wind turbine noise
The growing number of offshore wind farms will lead to an increase of anthropogenic noise in the sea. Research is therefore necessary to identify and minimize any potentially negative effects of offshore wind turbine noise on fish. To examine the potential impact of offshore wind farm noise emissions on cod (Gadus morhua) and plaice (Pleuronectes platessa), tank experiments were carried out exposing the fishes to different low frequencies at sound levels as emitted by wind turbines An annular concrete tank of 10 m in diameter was divided in connected quarters by sound barriers, so that sound pressure differences of 32 to 52 dB were achieved, depending on frequency and produced sound levels. Pure tones in the frequency range between 25 and 250 Hz were artificially emitted in sound levels of 130 and 140 dB re 1µPa. The experimental fish were free to move around in the tank and therefore could avoid the highest sound levels if they chose to. The location of fish in the 24 hour periods before, during and after sound production were compared and showed significantly lower numbers of cod in the vicinity of the sound source during sound presentation in the majority of the experiments. Reactions of plaice were ambiguous, suggesting both avoidance of, or attraction to the sound. From the results at least short-term changes in distribution of cod related to sound in the vicinity of offshore wind farms could be expected.
School:Humboldt-Universität zu Berlin
Source Type:Master's Thesis
Keywords:sound Pleuronectes platessa offshore wind farm research fish plaice behavioural reactions noise avoidance WR 3200
Date of Publication:02/27/2008