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von Benda-Beckmann, A.M. (author), Wensveen, P.J. (author), Kvadsheim, P.H. (author), Lam, F.P.A. (author), Miller, P.J.O. (author), Tyack, P.L. (author), Ainslie, M.A. (author)
Ramp-up or soft-start procedures (i.e., gradual increase in the source level) are used to mitigate the effect of sonar sound on marine mammals, although no one to date has tested whether ramp-up procedures are effective at reducing the effect of sound on marine mammals. We investigated the effectiveness of ramp-up procedures in reducing the area...
article 2013
document
Wensveen, P.J. (author), von Benda-Beckmann, A.M. (author), Ainslie, M.A. (author), Lam, F.P.A. (author), Kvadsheim, P.H. (author), Tyack, P.L. (author), Miller, P.J.O. (author)
The behaviour of a marine mammal near a noise source can modulate the sound exposure it receives.We demonstrate that two long-finned pilot whales both surfaced in synchrony with consecutive arrivals of multiple sonar pulses. We then assess the effect of surfacing and other behavioural response strategies on the received cumulative sound exposure...
article 2015
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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
document
von Benda-Beckmann, A.M. (author), Wensveen, P.J. (author), Prior, M. (author), Ainslie, M.A. (author), Hansen, R.R. (author), Isojunno, S. (author), Lam, F.P.A. (author), Kvadsheim, P.H. (author), Miller, P.J.O. (author)
To understand the consequences of underwater noise exposure for cetaceans, there is a need for assessments of behavioural responses over increased spatial and temporal scales. Bottom-moored acoustic recorders and satellite tags provide such long-term and large spatial coverage of behaviour compared to short-duration acoustic-recording tags....
article 2019
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von Benda-Beckmann, A.M. (author), Lam, F.P.A. (author), Moretti, D.J. (author), Fulkerson, K. (author), Ainslie, M.A. (author), van IJsselmuide, S.P. (author), Theriault, J. (author), Beerens, S.P. (author), TNO Defensie en Veiligheid (author)
The detection performance of a towed hydrophone array for deep-diving species is quantified by comparing detections of echolocation clicks from foraging groups of Blainville’s beaked whales (Mesoplodon densirostris) from the TNO Delphinus array to detections from bottom-mounted hydrophones at the Atlantic Undersea Test and Evaluation Center ...
article 2010
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Miller, P.J.O. (author), Antunes, R.N. (author), Wensveen, P.J. (author), Samarra, F.I.P. (author), Alves, A.C. (author), Tyack, P.L. (author), Kvadsheim, P.H. (author), Kleivane, L. (author), Lam, F.P.A. (author), Ainslie, M.A. (author), Thomas, L. (author)
Eight experimentally controlled exposures to 1−2 kHz or 6−7 kHz sonar signals were conducted with four killer whale groups. The source level and proximity of the source were increased during each exposure in order to reveal response thresholds. Detailed inspection of movements during each exposure session revealed sustained changes in speed and...
article 2014
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Sivle, L.D. (author), Kvadsheim, P.H. (author), Ainslie, M.A. (author), Solow, A. (author), Handegard, N.O. (author), Miller, P.J.O. (author), Nordlund, N. (author), Lam, F.P.A. (author)
Naval anti-submarine sonars produce intense sounds within the hearing range of Atlantic herring (Clupea harengus). In this study, schools of Atlantic herring were exposed to sonar signals of 1–2 kHz (low-frequency active sonar, LFAS) and 6–7 kHz (mid-frequency active sonar, MFAS) and playbacks of killer whale feeding sounds during their summer...
article 2012
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Kastelein, R.A. (author), Helder-Hoek, L. (author), van de Voorde, S. (author), von Von Benda-Beckmann, A.M. (author), Lam, F.P.A. (author), Jansen, E. (author), de Jong, C.A.F. (author), Ainslie, M.A. (author)
In seismic surveys, reflected sounds from airguns are used under water to detect gas and oil below the sea floor. The airguns produce broadband high-amplitude impulsive sounds, which may cause temporary or permanent threshold shifts (TTS or PTS) in cetaceans. The magnitude of the threshold shifts and the hearing frequencies at which they occur...
article 2017
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von Benda-Beckmann, A.M. (author), Wensveen, P.J. (author), Kvadsheim, P.H. (author), Lam, F.P.A. (author), Miller, P.J.O. (author), Tyack, P.L. (author), Ainslie, M.A. (author)
Ramp-up procedures are used to mitigate the impact of sound on marine mammals. Sound exposure models combined with observations of marine mammals responding to sound can be used to assess the effectiveness of ramp-up procedures. We found that ramp-up procedures before full-level sonar operations can reduce the risk of hearing threshold shifts...
bookPart 2016
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Lam, F.P.A. (author), Beerens, S.P. (author), Ainslie, M.A. (author), TNO Defensie en Veiligheid (author)
Naval operations in coastal waters are challenging the modelling support in several disciplines. An important instrument for undersea defence in the littoral is the LFAS sonar. To adapt to the local acoustic environment, LFAS sonars can adjust their operation depth to increase the coverage of the sonar. The optimal depth can be determined by a...
conference paper 2006
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Ainslie, M.A. (author), Dybedal, J. (author), Lam, F.P.A. (author), Simons, D.G. (author), Snellen, M. (author), TNO Defensie en Veiligheid (author)
The sensitivity of sound speed to temperature makes it possible to use an echo sounder as a thermometer, provided that the salinity and water depth are known with sufficient precision. Could ‘echothermometry’ – i.e., the use of an echo sounder, or a network of echo sounders, to measure temperature in this way – provide a viable alternative to...
conference paper 2005
document
von Benda-Beckmann, A.M. (author), Wensveen, P.J. (author), Kvadsheim, P.H. (author), Lam, F.P.A. (author), Miller, P.J.O. (author), Tyack, P.L. (author), Ainslie, M.A. (author)
Ramp-up (or soft-start) procedures are commonly used to mitigate the impact of sound on marine mammals. Although this procedure is often adopted as a common-sense approach, studies that quantify the effectiveness of ramp-up are currently lacking. The effectiveness of ramp-up is investigated by modelling the sound exposure of animals caused by a...
conference paper 2013
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