Searched for: author:"de Haan, D."
(1 - 9 of 9)
document
Bolle, L.J. (author), de Jong, C.A.F. (author), Bierman, S.M. (author), van Beek, P.J.G. (author), van Keeken, O.A. (author), Wessels, P.W. (author), van Damme, C.J.G. (author), Winter, H.V. (author), de Haan, D. (author), Dekeling, R.P.A. (author)
In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-)lethal effects occur is limited for...
article 2012
document
Jennings, N. (author), van der Veen, J. (author), de Haan, D. (author), Kastelein, R.A. (author), van der Heul, S. (author), Verboom, W.C. (author), TNO Defensie en Veiligheid (author)
World-wide, underwater background noise levels are increasing due to anthropogenic activities. Little is known about the effects of anthropogenic noise on marine fish, and information is needed to predict any negative effects. Behavioural startle response thresholds were determined for eight marine fish species, held in a large tank, to tones of...
article 2008
document
Kastelein, R.A. (author), Verboom, W.C. (author), Jennings, N. (author), de Haan, D. (author), TNO Defensie en Veiligheid (author)
The use of ultrasonic sounds in alarms for gillnets may be advantageous, but the deterring effects of ultrasound on porpoises are not well understood. Therefore a harbor porpoise in a large floating pen was subjected to a continuous 50 kHz pure tone with a source level of 122 +/- 3dB (re 1uPa, rms). When the test signal was switched on during...
article 2008
document
Kastelein, R.A. (author), de Haan, D. (author), Verboom, W.C. (author), TNO Defensie en Veiligheid (author)
It is unclear how well harbor porpoises can locate sound sources, and thus can locate acoustic alarms on gillnets. Therefore the ability of a porpoise to determine the location of a sound source was determined. The animal was trained to indicate the active one of 16 transducers in a 16-m -diam circle around a central listening station. The...
article 2007
document
Kastelein, R.A. (author), van der Heul, S. (author), van der Veen, J. (author), Verboom, W.C. (author), Jennings, N. (author), de Haan, D. (author), Reijnders, P.J.H. (author), TNO Defensie en Veiligheid (author)
World-wide many cetaceans drown incidentally in fishing nets. To reduce the unwanted bycatch in gillnets, pingers (acoustic alarms) have been developed that are attached to the nets. In the European Union, pingers will be made compulsory in some areas in 2005 and in others in 2007. However, pingers may effect non-target marine fauna such as fish...
article 2007
document
Kastelein, R.A. (author), Jennings, N. (author), Verboom, W.C. (author), de Haan, D. (author), Schooneman, N.M. (author), TNO Defensie en Veiligheid (author)
Small cetacean bycatch in gillnet fisheries may be reduced by deterring odontocetes from nets acoustically. However, different odontocete species may respond differently to acoustic signals from alarms. Therefore, in this study a striped dolphin and a harbour porpoise were subjected simultaneously to sounds produced by the XP-10 experimental...
article 2006
document
Kastelein, R.A. (author), van Schie, R. (author), Verboom, W.C. (author), de Haan, D. (author), TNO Defensie en Veiligheid (author)
The unmasked underwater hearing sensitivities of an 8-year-old male and a 7-year-old female Steller sea lion were measured in a pool, by using behavioral psychophysics. The animals were trained with positive reinforcement to respond when they detected an acoustic signal and not to respond when they did not. The signals were narrow-band,...
article 2005
document
Kastelein, R.A. (author), Janssen, M. (author), Verboom, W.C. (author), de Haan, D. (author), TNO Defensie en Veiligheid (author)
Receiving beam patterns of a harbor porpoise were measured in the horizontal plane, using narrow-band frequency modulated signals with center frequencies of 16, 64, and 100 kHz. Total signal duration was 1000 ms, including a 200 ms rise time and 300 ms fall time. The harbor porpoise was trained to participate in a psychophysical test and...
article 2005
document
Kastelein, R.A. (author), Rippe, H.T. (author), Vaughan, N. (author), Schooneman, N.M. (author), Verboom, W.C. (author), de Haan, D. (author), TNO Fysisch en Elektronisch Laboratorium (author)
In an attempt to test the effectiveness of sounds in deterring harbor porpoises from nets and reducing porpoise bycatch in gill net fisheries, two harbor porpoises, kept in a large floating pen at Neeltje Jans, The Netherlands, were subjected to 3 different underwater sounds. The effect of each sound was judged by comparing the animals' behavior...
article 2000
Searched for: author:"de Haan, D."
(1 - 9 of 9)