Searched for: author:"Verboom, W.C."
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von Benda-Beckmann, A.M. (author), Aarts, G. (author), Sertlek, H.O. (author), Lucke, K. (author), Verboom, W.C. (author), Kastelein, R.A. (author), Ketten, D.R. (author), van Bemmelen, R. (author), Lam, F.P.A. (author), Kirkwood, R. (author), Ainslie, M.A. (author)
(UXO) are still present in the North Sea. UXO are frequently accidentally encountered by fishermen and dredging vessels. Out of concern for human safety and to avoid damage to equipment and infrastructure from uncontrolled explosions, most reported UXO found in the Dutch Continental Shelf (DCS) are detonated in a controlled way. These underwater...
article 2015
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Kastelein, R.A. (author), Steen, N. (author), de Jong, C.A.F. (author), Wensveen, P.J. (author), Verboom, W.C. (author)
Naval sonar systems produce signals which may affect the behavior of harbor porpoises, though their effect may be reduced by ambient noise. To show how natural ambient noise influences the effect of sonar sweeps on porpoises, a porpoise in a pool was exposed to 1-s duration up-sweeps, similar in frequency range (6-7 kHz) to those of existing...
article 2011
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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
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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
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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
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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
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Lam, F.P.A. (author), Benders, F.P.A. (author), van IJsselmuide, S.P. (author), Verboom, W.C. (author), Camphuijsen, C.J. (author), TNO Defensie en Veiligheid (author)
From 28 June to 7 July 2005 the Netherlands Marine mammal Observations trial “NEMO” took place with HNLMS Mercuur. A track was sailed from Taranto (Italy) to La Coruña (Spain), passing the Straits of Messina and Gibraltar. Underwater acoustic transients were passively detected and classified with two towed arrays: the ‘operational’ CAPTAS array...
conference paper 2006
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Kastelein, R.A. (author), van der Heul, S. (author), Terhune, J.M. (author), Verboom, W.C. (author), Triesscheijn, R.J.V. (author), TNO Defensie en Veiligheid (author)
The marine aquaculture industry suffers losses due to pinniped attacks which damage net enclosures and fish stocks. Acoustic harassment devices (AHDs) emit loud sounds which are intended to deter pinnipeds from approaching aquaculture enclosures. At present, many AHDs emit sounds in the 8-20 kHz frequency range. It is not known whether sounds of...
article 2006
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Kastelein, R.A. (author), van der Heul, S. (author), Verboom, W.C. (author), Triesscheijn, R.J.V. (author), Jennings, N.V. (author), TNO Defensie en Veiligheid (author)
To prevent grounding of ships and collisions between ships in shallow coastal waters, an underwater data collection and communication network (ACME) using underwater sounds to encode and transmit data is currently under development. Marine mammals might be affected by ACME sounds since they may use sound of a similar frequency (around 12 kHz)...
article 2006
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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
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Verboom, W.C. (author), Kastelein, R.A. (author), TNO Defensie en Veiligheid (author)
World-wide a concern exists about the influence of man-made noise on marine life and particularly on marine mammals and fish. One of the acoustic polluters of the world’s oceans is high-power active sonar, but also pile driving and seismic activities at sea are of concern with respect to animal welfare. At TNO, acoustic criteria are being...
conference paper 2005
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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
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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
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Kastelein, R.A. (author), Verboom, W.C. (author), Muijsers, M. (author), Jennings, N.V. (author), van der Heul, S. (author)
To prevent grounding of ships and collisions between ships in shallow coastal waters, an underwater data collection and communication network is currently under development: Acoustic Communication network for Monitoring of underwater Environment in coastal areas (ACME). Marine mammals might be affected by ACME sounds since they use sounds of...
article 2005
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Benders, F.P.A. (author), van der Zwan, T. (author), Verboom, W.C. (author), TNO Defensie en Veiligheid (author)
Knowledge about habitats and behaviour of marine animals has become more important following an increased concern that acoustic sources may have an influence on marine life. Databases containing the habitats and behaviour are being filled all over the world. However, at present marine mammal watchers do not have appropriate tools to support the...
conference paper 2005
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Benders, F.P.A. (author), Beerens, S.P. (author), Verboom, W.C. (author), TNO Fysisch en Elektronisch Laboratorium (author)
World-wide a concern exists about the influence of man-made noise, and particularly of high power sonar, on marine life and divers in the sea. Most concern lies with marine mammals that use acoustics for hunting, communication and/or navigation. This concern is fed by recent strandings of whales that could be related to military sonar...
conference paper 2004
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Benders, F.P.A. (author), Beerens, S.P. (author), Verboom, W.C. (author), TNO Fysisch en Elektronisch Laboratorium (author)
World-wide a concern exists about the influence of man-made noise on marine life, and particularly of high power sonar. Most concern lies with marine mammals that use acoustics for hunting, communication and/or navigation. This concern is fed by recent strandings of whales that could be related to military sonar transmissions and seismic...
conference paper 2004
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Verboom, W.C. (author), Kastelein, R.A. (author), Technisch Physische Dienst TNO - TH (author)
Since July 1993, a systematic study on harbor porpoise (Phocoena phocoena) acoustic signals was conducted in the Netherlands. The first general results were published in Verboom and Kastelein (1995, 1997). Studied were animals kept for veterinary treatment in the Cetacean Rehabilitation Centre at Harderwijk, after being stranded on the Dutch...
conference paper 2003
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Benders, F.P.A. (author), Beerens, S.P. (author), Verboom, W.C. (author), TNO Fysisch en Elektronisch Laboratorium (author)
World-wide a concern exists about the influence of man-made noise on marine life, and particularly of high power sonar. Most concern lies with marine mammals that use acoustics for hunting, communication and/or navigation. This concern is fed by recent strandings of whales that could be related to military sonar transmissions and seismic...
conference paper 2002
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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:"Verboom, W.C."
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