Perception of low-frequency acoustic signals by a harbour porpoise (Phocoena phocoena) in the presence of simulated offshore wind turbine noise
Klaus Lucke
Paul Lepper
Bert Hoeve
Eligius Everaarts
Niels van Elk
Ursula Siebert
2134/3846
https://repository.lboro.ac.uk/articles/journal_contribution/Perception_of_low-frequency_acoustic_signals_by_a_harbour_porpoise_Phocoena_phocoena_in_the_presence_of_simulated_offshore_wind_turbine_noise/9563696
Using auditory evoked potential (AEP) methods,
a study was conducted on a harbour porpoise
(Phocoena phocoena) at the Dolfinarium
Harderwijk in The Netherlands. The study measured
the audible range of wind turbine sounds
and their potential masking effects on the acoustic
perception of the animal. AEPs were evoked
with two types of acoustic stimuli: (1) click-type
signals and (2) amplitude-modulated signals. The
masking noise resembling the underwater sound
emissions of an operational wind turbine was
simulated. At first, the animal’s hearing threshold
was measured at frequencies between 0.7 and
16 kHz. Subsequently, these measurements were
repeated at frequencies between 0.7 and 2.8 kHz
in the presence of two different levels of masking
noise. The resulting data show a masking effect
of the simulated wind turbine sound at 128 dB re
1 μPa at 0.7, 1.0, and 2.0 kHz. This masking effect
varied between 4.8 and 7.3 dB at those frequencies.
No significant masking was measured at a
masking level of 115 dB re 1 μPa. The available
data indicate that the potential masking effect
would be limited to short ranges in the open sea,
but limitations exist to this conclusion and all
estimates are based on existing turbine types, not
taking into account future developments of larger
and potentially noisier turbine types.
2008-11-03 10:31:08
Harbour porpoise
Phocoena phocoena
Acoustic perception
Masking
Auditory evoked potentials
North Sea
Offshore wind turbines
Mechanical Engineering not elsewhere classified
Zoology