Oceans of noise - Whale and Dolphin Conservation Society

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However they also noted that whales may simply habituate to the sound, or not learn to use it as acue that indicates the presence of fishing gear.The predator species concerned, as well as the source level and frequency of the device used, arelikely to affect the level of success initially. Yet both AHDs and ADDs may ultimately providethe ‘dinner bell’ effect, where alarm may give way to eventual habituation to the devices, andeven attraction that may be initiated by association of the sound with an easy meal. Therefore,caution is warranted where considering the use of such devices. Studies that have been conductedover a number of years have shown varying results in effectiveness to date.Participants in a US Department of Commerce workshop (NOAA 1996) have repeatedlyemphasised that artificial sound should be introduced into the underwater environment only whenthe costs and benefits of doing so are clearly understood, and only after the potential ecologicalconsequences have been carefully considered. The does not seem to be the general practice withAHDs and ADDs as they continue to proliferate worldwide, largely as a quick-fix solution.Gordon and Northridge (2001) make some useful general recommendations as well as morespecific recommendations on addressing knowledge gaps on the effects of ADDs, improveddevelopment of ADDs and on distribution, abundance and biology of vulnerable wildlife. Thesecould equally be applied to AHDs.3.9. DredgingDredging comes in many forms: it can be for removing silt and sediment from the seabed, or as ameans of fishing for shellfish. Several studies have documented the effects of underwater noiseproduced by dredging operations on cetaceans. For example, grey whales avoided the LagunaGuerro Neggro, Baja, California, for several years after dredging operations started in the area(Bryant et al. 1984).In addition, bowhead whales exposed to playbacks of dredger noise recordings at broadbandreceived levels of 122-131 dB were displaced from the area (Richardson et al. 1985a, 1985b;1990; Wartzok et al. 1989). Bowhead whales stopped feeding and moved until they were over2km away from the sound source. Moreover, whale vocalisations decreased and changes insurfacing, respiration and diving patterns were recorded (Richardson et al. 1985a, 1985b;Wartzok et al. 1989). However, bowhead whales were also observed within 800m of suctiondredgers where noise levels of 120dB were detected at 1.2km from the site (Richardson et al.1985b, 1990). Therefore, although dredging has been shown to be a source of underwater noisepollution, further investigation into the effects on marine mammals is required.3.10. Marine Wind FarmsOffshore wind farms have the potential to make a large contribution to renewable energyproduction. As a relatively new area of development, there is a lack of detailed informationconcerning potential impacts on marine life, including cetaceans (see, for example, Vella et al.2001; Henriksen et al. 2001).Possible direct negative impacts might include noise disturbance and habitat loss. There may alsobe indirect effects on cetaceans, as impacts from the turbines and connecting sub-sea cables mayresult in changes to the local sediment patterns, which may lead to habitat changes in the vicinityof the wind farm. This may have knock-on effects on local prey species, such as fish andinvertebrate populations. Establishing offshore wind farms is a large-scale and long-term activityfor which thorough environmental evaluation should be required.43
3.11. Research3.11.1. Controlled Exposure Experiments and ‘playback’To improve the knowledge and understanding of the impacts of anthropogenic noise on shortterm and observable cetacean behaviour, some efforts have been made to expose cetaceans tospecific sounds with the aim of monitoring their responses. Such studies are aimed at filling datagaps that currently exist regarding responses to specific potentially damaging sounds,vulnerabilities of different species, and individual groups within those species (for examplemother and calf pairs) and perhaps most urgently, the assessment of auditory thresholds.A strong case should have to be made that such studies can produce valid results that cannot beachieved by less intrusive means. This approach only allows short-term and well knownbehaviours to be monitored (Gordon and Thompson 2001) and may have long term implicationsfor those animals involved. The link between possible behavioural responses and the onset ofphysical damage cannot currently be determined. Further to this, no obvious or measurableresponse does not mean there is no impact.Introducing further noise into the marine environment obviously has a potential to negativelyaffect those individuals that are being targeted, and may also have implications for others.44
Page 2: Oceans of Noise 2004A WDCS Science
Page 8 and 9: In the US, the deployment of Low Fr
Page 10 and 11: its propagation beyond those declar
Page 12 and 13: The best evidence for noise being f
Page 14 and 15: Box 1. Characteristics of sound / l
Page 16 and 17: Sound speed (c)The speed (c) of a w
Page 18 and 19: Box 2. The effects of temperature,
Page 20 and 21: 2.1.2. Measuring sound intensityIde
Page 22 and 23: i.e. Equal pressure measurements di
Page 24 and 25: Spherical or Geometrical spreading
Page 28 and 29: 5.0 145Tug pulling loaded barge 1.0
Page 30 and 31: The source used during 3-D surveys
Page 32 and 33: Machinery noisePropulsion machinery
Page 34 and 35: Man-made islands /caissonsFixed pla
Page 36 and 37: 12 3245Drill bit6Figure 3.4. Sound
Page 38 and 39: Transientnoise sourcesAircraftHelic
Page 40 and 41: Results from the aerial surveys con
Page 42 and 43: haemorrhaging in the inner ears and
Page 46 and 47: 4. The Use of Sound by CetaceansChr
Page 48 and 49: seems logical, therefore, that if t
Page 50 and 51: However, despite the reported low a
Page 52 and 53: Kamminga and Wiersma 1981;Akamatsu
Page 54 and 55: SongSocial callsShrieksSlaps0.03-80
Page 56 and 57: anthropogenic factors that make the
Page 58 and 59: 5.3 Longer-term impactsNoise is cle
Page 60 and 61: 5.4 Indirect impactsThe above impac
Page 62 and 63: decompression sickness (DCS) as see
Page 64 and 65: 6. Examples of regional and nationa
Page 66 and 67: 6.3 ASCOBANS and ACCOBAMSTwo region
Page 68 and 69: implications and the discussion sho
Page 70 and 71: 7.1. Consideration of Voluntary vs.
Page 72 and 73: acoustic measurements have been mad
Page 74 and 75: 7.6. Methods of protectionComplianc
Page 76 and 77: 7.6.1 Monitoring7.6.1.1 Visual, aco
Page 78 and 79: Delory et al. (2002) use Ambient No
Page 80 and 81: 8. ReferencesAburto, A., Rountry, D
Page 82 and 83: Caldwell, M.C., Caldwell, D.K., and
Page 84 and 85: Engas, A., Lokkeborg, S., Ona, E. a
Page 86 and 87: IWC 2002b. Report of the Scientific
Page 88 and 89: McCauley, R.D. 1994. Seismic Survey
Page 90 and 91: Potter, J. and Delory, E. 2001. Noi
Page 92 and 93: Smolker, R.A., Mann, J. and Smuts,
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Watkins, W.A. 1981b. The activities
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ANNEX 1The Application of Marine Po
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an important factor. 13 The judgeme
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in the preparatory work of the LOSC
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practice by the UNEP Governing Coun
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protection and preservation of the
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than international rules, standards
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Four of the twelve regional seas tr
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seismic operations in the Protocol
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ConclusionAt the global level, only
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Art 209 LOSC focuses on both standa
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No State Party may impose condition
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coastal States”. This formulation
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If the IMO makes this determination
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estrictions to vessels operating in
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In the EEZ, in comparison to the te
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Appendix A - Some international ins
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Convention for the Protection of th
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Available at:http://www.unep.ch/sea
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BucharestConventionArticle XIPollut
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environment1. The Contracting Parti
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- that under Article III.8.c) of AC
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e) no sudden or repeated change in
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Ref: Nowacek et al. 2001.Location:
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Location: Arctic• Vocal behaviour
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• Vaquita surfacing duration and
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• 6% of small delphinids (n=264;
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Species type: Boto, Inia geoffrensi
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• Humpback whales appeared tolera
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• Behaviour interpreted as aggres
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• There was no evidence of minke
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• Northern right whales may be ap
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• Migrating gray whales disturbed
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to Ensenada De La Paz, Mexico. Aqua
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distribution of humpback whales, Me
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Richardson, C.R. Greene, C.I. Malme
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Zhou, K., Pilleri, G. and Li, Y. 19
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6. surveys for Cuvier’s beaked wh
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Oceans of noise - Whale and Dolphin Conservation Society

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