Racket in the Héloïse Berkowitz, Hervé Dumez

To cite this version:

Héloïse Berkowitz, Hervé Dumez. Racket in the Oceans: Why Underwater Noise Matters, how to Meassure it, and how to Manage it. [Other] i3-Centre de Recherche en Gestion (École polytechnique - CNRS); Observatoire de l’Innovation Responsable (Mines ParisTech). 2017. ￿hal-01486973￿

HAL Id: hal-01486973 https://hal.archives-ouvertes.fr/hal-01486973 Submitted on 10 Mar 2017

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A position paper by the Observatory for responsible innovation (Institut Interdisciplinaire de l’Innovation – i3 UMR 9217)

coordinated by Héloïse BERKOWITZ & Hervé DUMEZ

cover illustration: Michèle Breton (on an idea by Hervé Dumez)

Palaiseau (France)

i3-Centre de Recherche en Gestion (École polytechnique - CNRS) et Observatoire de l’Innovation Responsable (Mines ParisTech)

2017

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Acknowledgements

The Observatory for Responsible Innovation acknowledges the many contributors to this position paper1: The working group (coordinated by Héloïse Berkowitz and Hervé Dumez), composed of Christian Audoly (DCNS), Eric Baudin (Bureau Veritas), Fabian Muniesa (Mines ParisTech, chairman of the Observatory), Aldo Napoli (Mines ParisTech), Céline Rousset (DCNS); The participants to the Marine series of workshops organized by the Observatory for Responsible Innovation, with special thanks to Michel André; Michèle Breton (i3-CRG, École polytechnique, CNRS, Université Paris Saclay). We also thank Bureau Veritas and Paris Sciences & Lettres (PSL) University for their contribution to the organization of the conference.

1 How to quote this position paper: Berkowitz Héloïse & Dumez Hervé [eds] (2017) Racket in the oceans: why underwater noise matters, how to measure and how to manage it. Paris: Observatory for Responsible Innovation / Palaiseau (France): i3-CRG (CNRS – École polytechnique).

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Content

ACKNOWLEDGEMENTS 3

 Foreword: Addressing noise 9 Michel André  Executive Summary 11  List of contributors 13

INTRODUCTION AND SYNTHESIS 15

 Racket in the oceans 17 Héloïse Berkowitz & Hervé Dumez What do we know about the impact of noise on animals? 18 What is sound and how to measure it in ocean? 21 A comprehensive approach to 24 Governance Framework 27 Conclusion 29 References 29

SCIENTIFIC, TECHNICAL AND MANAGERIAL CONTRIBUTIONS 31

 Contrasting whale behavioral responses to anthropogenic noise and predator presentations to assess biological significance 33 Charlotte Curé & Patrick Miller Introduction 33 Methods 34 Results 35 Discussion 35 Conclusion 36 References 36  High performance modeling of the propagation of biological in the ocean: new numerical tools in the study of cetaceans 39 Dr Julie Patris, Pr Mark Asch, Pr Hervé Glotin, Dr Dimitri Komatitsch, Dr Elwin van’t Wout, Dr Susannah Buchan & Dr Franck Malige Introduction 39 General idea of the method 39 Modeling softwares 39 First tests of the method 40 Field measures and validation 41 Ship noises 41 Conclusion 41 References 42  Surface Ship Pass-by Noise for Sound Source Identification 45 Benoit Oudompheng, Barbara Nicolas, Arthur Finez & Agnès Gerphagnon References 47

5  Review on Existing Data on Underwater Sounds Produced by the Oil and Industry (for the Joint Industry Programme) 49 Nikhil Banda, Rachel Glanfield & Roy Wyatt References 50  Standardization in – needs and status 51 Christian Audoly Introduction 51 Needs for standardization in underwater acoustics 51 Status of actions for standardization at international level 52 Summary and way ahead 53 References 53  How efficient are potential regulations on underwater noise? A framework proposed by the AQUO project 55 Éric Baudin, Céline Rousset, Christian Audoly, Thomas Folegot & Michel André Introduction and context 55 Methodology overview 55 Applicability 57 Acknowledgements 58 References 58  How does the Marine Strategy Framework Directive protect European & oceans from the impacts of underwater noise? 59 Lydia Martin-Roumégas EU laws protecting the marine environment from adverse underwater noise effect 59 The ‘Good environmental status’ Decision: more focus on state & notions 61 Achievements of the MSFD technical group on underwater noise 62 Future objectives, tasks for the MSFD technical group on underwater noise 62 Mains issues and conclusions 63 Main reference documents on underwater noise and MSFD at European level 63  From Paper to Practice: Appropriately Assessing Anthropogenic Noise in Our Oceans 65 Nicolas Entrup, Geoff Prideaux & Margi Prideaux EIAs for Marine Noise in Europe 65 Guidelines for Marine Noise 66 Marine Noise EIA Content 66 The Utility of EIAs 68 References 69  Controlling Underwater Noise from Ships 73 Jesse H. Spence & Raymond W. Fischer Abstract 73 Introduction 73 Vessel noise sources and solutions 74 Costs 75 Conclusions 76 References 76

6  What means to protect sensitive marine mammals from piling noise of offshore windfarms foundations installation? 79 Rémi Casteras, Rassim Hariz & Yohan Weiller Noise mitigation systems (NMS) 79 Deterrence means take marine mammals away from impacted zones 80 Conclusion 81 References 81  Addressing underwater noise in maritime projects: Importance, control and mitigation and future perspectives 85 Aleyda Ortega & Henk van Vessem Importance of the issue for the maritime industry 85 The need for maritime operating companies to address underwater noise 85 Noise Mitigation System for pile driving: technology and development trajectory 86 Use of additional methods: e.g. deterring systems and bubble screens 87 developments and future perspectives 87 References 88  The Enhancing Cetacean and (ECHO) Program: A port authority-led collaborative initiative working to reduce cumulative noise impacts of commercial vessel activity on an endangered killer whale population 91 Orla Robinson Background Context 91 ECHO program description and goals 91 A collaborative approach 91 Projects and studies to inform mitigation and regional management – Acoustic disturbance 92 Regional Management Applications. Project highlight – Strait of Georgia Underwater listening station 92 Regional Management Applications. Project highlight – Regional acoustic modelling and noise budget 93 Global Applications 93  Regional management of underwater noise made possible: an achievement of the BIAS project 95 Thomas Folegot, Dominique Clorennec, Anna Nikolopoulos, Frida Fyhr, Mathias Andersson & Peter Sigray Introduction 95 Mapping the Baltic 95 Utilizing the noise maps within regional management 96 Conclusion 97 Acknowledgements 97 References 98  Embedded processing technologies for underwater noise monitoring: experience from the German Offshore Windfarms 101 Luc Simon, Caroline Magnier & Federica Pace Underwater noise embedded processing challenge 101 Real-time noise monitoring 102 Real-time noise monitoring benefits: examples 102 References 103

7  Progress in addressing man-made noise in the Mediterranean Sea: assessment and regulation at a basin-wide scale 105 Alessio Maglio, Gianni Pavan, Manuel Castellote, Silvia Frey & Maylis Salivas Introduction 105 Initiatives for regulating and assessing underwater noise emissions 105 Discussion and Conclusion 107 References 108

APPENDIX 111

 Presentation of the project 113 The Observatory for Responsible Innovation and i3 113 Organization of the project 113  Lexicon/Glossary 123

8 FOREWORD: ADDRESSING OCEAN NOISE

Michel André Technical University of Catalonia, BarcelonaTech (UPC), Spain

The range of visibility in the aquatic world is trauma in mass stranded cetaceans, there is limited as a result of the attenuation of still no clear evidence of it, even when the in . As a consequence, early aquatic stranding event was related to exposure to animals have learned to use sounds to loud artificial sources. As we learn more gather information on their environment. about the effects of noise on other species, The evolution of an auditory system that can we may find that marine mammals do not discriminate among sounds, determine the primarily suffer from a direct exposure to direction of a particular sound source, and sound on the short-term, but may be detect it even when the environment is indirectly affected at population levels somewhat noisy, greatly increased the because of the impact of noise on their survival potential of those animals. Whether preys. the most important function of hearing is communication or learning about We may also witness changes in the surrounding environments, for example in behavior of major predators, such as sperm order to detect preys or predators, sound is whales, which may choose to expose critical for most marine organisms. themselves to the intense acoustic energy Anthropogenic sound sources have the derived from offshore operations after potential to affect this channel of natural learning that squids potentially become knowledge by masking the vital extraction debilitated by the noise those operations of general information from the generate. environment. Injuries, which could be Despite the attention now widely paid to defined as a temporary or permanent ocean noise issues, knowledge is still hearing impairment, have also been limited. Time, however, is running out for described in different marine taxa after providing regulators with consensual data exposure to noise. An important question is that would prompt limiting the impact of therefore whether the impact of man-made sounds on marine . anthropogenic sounds on marine animals is Ocean noise actors, including industry, sufficiently serious to raise the concern of environmental agencies and NGOs, have the the scientific community and the public. responsibility to learn from each other, put The data currently available suggest that behind past obvious incompatibilities, and such concern would indeed be justified. work together towards a responsible use of ocean resources. Concerns about ocean noise were initially focused on the effects of artificial noises on Initiatives like “Racket in the Oceans” show marine mammals and later on . the appropriate way of facilitating the However, given marine invertebrates’ necessary interchanges among ocean noise capacity to use sounds to carry out most of parties, with fundamental and applied their activities, recent findings on their science as the basis for seeking a balance sensitivity to noise has increased scientific between industrial and societal interests alarm to the point of turning the issue of and wildlife conservation. ocean noise into a problem to be dealt with at the scale of ecosystems. As a matter of fact, although a lot of effort has been made in the last two decades to reveal acoustic

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EXECUTIVE SUMMARY

This position paper is devoted to the 3. Solutions to mitigate underwater noise problem of anthropogenic noise in the from activities are becoming oceans, and is addressed to public and available. Although all human activities private decision makers. Underwater noise at sea produce noise, it is generally is recognized as a major problem for in agreed that shipping, Oil and Gas E&P, and renewable energy operations are the oceans, which represent 70% of the primarily concerned. surface of the . We shall develop four 4. The central question for public and key points: private decision-makers is how to 1. Although there is no synthetic and change quickly and adapt the behavior general knowledge regarding the of industrial stakeholders so as to impact of noise on all marine species, reduce underwater noise. Regulations there is by now a reliable and are needed at the state level, at the consistent body of evidence that the level of port authorities, and of problem is far more serious than had authorities managing marine protected been suspected, and that it deteriorates areas. Incentives and subsidies are from year to year. When discussing the probably necessary to help industries effects of underwater noise, we think evolve and adopt available techniques. immediately of marine mammals, like Underwater noise is a complex whales and dolphins, which strongly management problem because of its rely on sound to communicate, forage scale and the multiplicity of concerned and orientate. Noise can disrupt actors. We must share knowledge and behaviors such as feeding or breeding. information, and map areas in terms of We now also know that intense noise. We must also create institutions anthropogenic sources have the that bring different stakeholders potential to cause cetacean strandings. together and are capable of devising But some also communicate both long-term and real-time solutions. through sound and, can be therefore The first part of this position paper develops deeply disturbed by noise. Besides, these four points. The second part outlines studies have shown that animals that the scientific knowledge we have about the do not possess hearing organs, such as effects of underwater noise, the problem of invertebrates, can also be permanently noise measurement, readily available affected by exposure to noise, and techniques to reduce noise or its effects, and eventually die as a consequence. cases of regulation. It aims at sketching the 2. An indicator of noise disturbance is problem as it is understood today, and at required to manage the problem. Though recognizing that there is no supporting the efforts to be done by perfect measurement system, we must managing properly the stakes. quickly establish a standardized, simple This position paper is a collective work. We and reliable procedure. But while the thank the members of the working group, European MSFD has provided Member States with guidelines on how to Christian Audoly, Eric Baudin, Aldo Napoli, measure and report noise levels under Céline Rousset, the co-organizers of the Descriptor 11, there is so far no three workshops and the panelists of the agreement on the noise disturbance conference held in Paris (20 September indicators to be adopted. Uncertainties 2016), with a special mention to Michel remain as to which species are affected André. in what circumstances and , as well as concerning the role of specific sound source components in triggering damage to receptors.

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LIST OF CONTRIBUTORS

Mathias ANDERSSON Alessio MAGLIO Michel ANDRÉ Caroline MAGNIER Mark ASCH Franck MALIGE Christian AUDOLY Lydia MARTIN-ROUMÉGAS (European Commission) Nikhil BANDA Patrick MILLER Éric BAUDIN Barbara NICOLAS Héloïse BERKOWITZ Anna NIKOLOPOULOS Susannah BUCHAN Aleyda ORTEGA Manuel CASTELLOTE Benoit OUDOMPHENG Rémi CASTERAS Federica PACE Dominique CLORENNEC Julie PATRIS Charlotte CURÉ Gianni PAVAN Hervé DUMEZ Geoff PRIDEAUX Nicolas ENTRUP Margi PRIDEAUX Arthur FINEZ Orla ROBINSON Thomas FOLEGOT Maylis SALIVAS Raymond W. FISCHER Peter SIGRAY Silvia FREY Luc SIMON Frida FYHR Jesse H. SPENCE Agnès GERPHAGNON Henk VAN VESSEM Rachel GLANFIELD Elwin VAN’T WOUT Hervé GLOTIN Yohan WEILLER Rassim HARIZ Roy WYATT Dimitri KOMATITSCH

13

Introduction and synthesis

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RACKET IN THE OCEANS

Héloïse Berkowitz & Hervé Dumez i3-CRG, École polytechnique, CNRS, Université Paris-Saclay

Seen from space, the Earth offers the Various attempts at reducing or at least beautiful appearance that earned it the taking into account underwater noise nickname “ Marble”. The oceans cover pollution have been already made. For more than 70 percent of the Earth’s surface. instance, impact surveys are now obliged to For a long time, human beings deemed them address acoustic pollutions and their too big and too deep to be impacted by their negative effects on species. Seasonal activities. We now know too well how restrictions of economic activities aim to untrue this is: from overfishing to prevent sound from disturbing nesting acidification, plastic waste and harmful algal periods. Exclusion zones have been defined, blooms, sustainable ocean management where no sound-intensive activity can occur raises major issues related to at all. Existing legislation often requires change and pollution. Some of these topics, Marine Mammal Observations (MMO), such as plastics or overfishing, have been intended in particular to avoid vessel-whale given considerable media coverage. Others collisions or ship strikes. Another required less so: that is the case of marine sound. And procedure, called soft-start, consists in yet marine transportation, oil and gas slowly increasing the sound levels at the exploration, and the exploitation of source. However, what happens if animals renewable marine energies generate a real habituate to the noise and remain in the racket in the oceans. zone? Acoustic emissions will end up hurting them. Other regulations propose to Scientists are beginning to better establish noise level restriction, but that understand the extremely worrying impacts raises the problem of defining the of marine sound on marine fauna. Animals restrictions. What is a good threshold? What that use sound to communicate underwater about the case of multiple sound sources count among the first victims of noise present in a given area? pollution. Anthropic emissions directly affect them. Whale beach stranding To protect marine fauna from underwater constitutes only the most visible case. noise pollution and preserve biodiversity, Indeed, as recently discovered (André et al., managers and decision makers need a 2011), even animals such as squids, which certain number of capabilities to address do not hear sounds as mammals do, can also such sound issues as behavioral response be gravely touched. Effects are far-reaching comprehension, noise measurement and on all , from cetaceans to prediction, or bio-sound detection. This invertebrates and fish. Exposure of marine situation contributes to the development of fauna to sound pollution results in a range many new activities around sound, of behavioral responses, physiological including measurement, modeling, signal effects and physical injuries. It can also have processing, and impact assessment. These ecological, population and cumulative constitute both challenges and effects, with dire consequences on the opportunities for marine industries, ocean overall worldwide . Too many conservation actors, and public decision simultaneous , for instance makers. overfishing and marine sound together, risk bringing about a tipping point where This position paper aims at providing a species disappear and whole ecosystems synthetic view of the problem of collapse. underwater acoustic pollution and of ways to address it. It begins with a state-of-the-art of existing scientific knowledge about the

17 impact of noise on marine fauna. It then A reliable and consistent body of evidence examines the complex technical question of noise measurement. Finally, it deals with “If you look at all the recent strandings incidents, about half a dozen, you see a potential solutions: from the technical to the good correspondence between a ship track managerial, some already exist, but putting and the timing of the strandings. And it is them into practice remains difficult. consistently beaked whales that is the Changing behavior or encouraging species most affected”, (Geotimes, 2003) implementation can occur through financial incentives, regulation or nudge strategies. Sound is a variation of pressure and thus it can potentially affect any living organism. With this position paper, we hope to raise Effects of underwater acoustic pollution awareness of the issue of underwater noise range from behavioral perturbations to among public and private decision makers, physical injuries or even the animal’s death. and offer them information that can help Direct perturbations of the auditory system them collectively design and implement likely constitute the worst type of effect. solutions. However, exposure to underwater noise pollution can influence stress levels, as it What do we know about the impact of was shown with beluga whales (Romano et noise on animals? al., 2004). Animals produce sounds or use sound There are four zones with different levels of features to communicate, recognize each impact on species: other, hunt, locate themselves and their congeners, navigate, and reproduce.  The zone of audibility, where animals can (Wartzok & Ketten, 1999). Introducing in pick up anthropic underwater noise. the ocean anthropic-originated sound, that  The masking zone where noise actually interferes with an animal’s use of sounds is, underwater acoustic pollution, might (to detect other animals, to interpret, to therefore affect animals. hunt, and so forth). Things happen here There is a worldwide reliable and consistent as when two human beings try to body of evidence about sound’s effects on communicate while passing by a construction site: since their voices are different species of marine fauna. Taken masked by the construction’s racket, it is separately, these pieces of evidence may not difficult to hear one another. seem worrisome; considered together, they  The responsiveness zone where sound show that acoustic pollution has to be taken directly affects the animal’s behavior. seriously.  The mortality or injury zone. Scientists acknowledge the effect of Impact studies have to take into account underwater acoustic pollution on animals. different parameters, such as animals We first think of marine mammal, but it has moving and having different reactions been demonstrated that other species are depending on the context (they could be also affected, including fish like cod, which feeding, breeding, or socializing), on the communicate while mating. Effects are even characteristics of the water, and other broader than one could imagine, since they factors. It is therefore difficulty to isolate can touch species such as invertebrates, and identify effects and causality links, and which do not use sounds to communicate. that is why so many controlled experiments are needed, and controls of controls. Scientists are also increasingly aware of the difficulties involved in understanding and Underwater acoustics has two components: evaluating the impact of marine sound on pressure and particle-motion. Marine fauna, difficulties that are partly due to the mammals are sensitive to sound pressure very complexity of marine ecosystems due to their hearing apparatus, but most themselves. fishes and invertebrates are more sensitive to sound particle motion (Nedelec, Campbell, Radford, Simpson, & Merchant, 2016). Different species with varied

18 complex physiologies are affected very in the Atlantic, Pacific and Indian differently, and research has to be tailored Oceans and the Mediterranean Sea to accordingly. protect mammals. This decision was made at a time when evidence increasingly shows What do we concretely know today about that whales do respond to underwater the relevant species? noise.  Mammals Numerous at-sea experiments have shown The frequencies of sonar systems vary from how different range frequencies impact on very low (infrasonic) to extremely high different types of mammals, from cetaceans (ultrasonic). Military uses of active sonar to pinnipeds (Curé et al., 2012; Miller et al., systems usually operate in a mid or low- 2014). Whales strandings are only the most frequency range of acoustic emission. These spectacular instance of a wide array of systems’ potential danger harmful effects. Underwater became evident in 2000, after noise has been shown to beach strandings of whales of How do you study impacts of disrupt feeding and other four different species sound on mammals? vital behavior, and to cause occurred in the Bahamas. Mid- “You need a baseline which marine mammals to frequency sonar was highly gives you the normal pattern and flee, or, still worse, to suspected of causing the behavior, within a particular remain and be strandings. The US Navy functional context. Then you physiologically affected. initially denied any quantify the behavioral responsibility, but it was clear responses to anthropogenic More questions remain noise. And finally you the danger increased with concerning the cumulative compare responses to a growing source levels of effects of different sources of reference model of disturbed noise on mammals. active sonar and the use of behavior”. (Charlotte Curé, lower frequencies. Workshop on Impacts, 10th of  Invertebrates After this incident, beaked March, 2016) About ten years ago for the whales nearly disappeared first time, people witnessed from the area. Researchers giant squid strandings off the concluded that whales had either Spanish coast. At the time, scientists abandoned their habitat or died after the suspected that sonar pulses had injured the sonar event. Since then, similar mass animals. As with mammals, however, hard strandings have been witnessed in the evidence was lacking. Canary Islands, Greece, Madeira, the U.S. Virgin Islands, Hawaii and other sites Laboratory experiments have now shown around the globe, each time concomitantly that low-frequency underwater emissions to major sonar uses. Direct causality has so from human activities can indeed affect far not been demonstrated, but the squid and other cephalopods (André et al., recurrence of simultaneous sonar use and 2011). Thus, the problem does not concern strandings has raised suspicion. only whales and other marine mammals, which have been long considered vulnerable One of the main obstacles to prove a causal to acoustic emissions. It touches also link between sonar pulses and whale beach invertebrates, a whole group of different strandings is that the animal’s , once marine species that, paradoxically, are not outside of water, degrades very quickly. known to use sound for living. Thus, when scientists or experts arrive at the stranding site, it is generally too late to Experimental research has examined the perform a necropsy, i.e. to examine the effects of low-frequency emissions exposure animal and determine the cause of death. on 87 animals from four different invertebrate species: two of squid, one of Nevertheless, in July 2016, the Ninth U.S. octopus, and one of cuttlefish. The findings Circuit Court of Appeals ordered the US suggest that underwater noise pollution has Navy to reduce the use of low-frequency much broader effects on marine life than

19 anticipated, as it showed that individuals More knowledge is needed on topics such as suffered massive acoustic trauma on their the effects on migratory fish species of statocysts, which help them move, sometimes electromagnetic fields and sound emissions even followed by peripheral damage that made generated by marine renewable energy. It is things worse over time. necessary to link reactions, such as migratory fish changing route, to real long- This could certainly explain the death of the term impact, on which data is still giant squids stranded in Spain: they could unfortunately lacking. have been directly killed by sonar pulses; or perhaps their statocysts had been Cumulative dose effects and risks for destroyed, could no longer orient ecosystems themselves, and wandered to the surface, where the change of killed There are in the ocean multiple sources of them. There is little doubt now that marine sound, both from human activities, and from invertebrates are sensitive to low frequency the natural and animal worlds. We should sounds, which may be linked to a be concerned about the potential combination of sound pressure and particle cumulative impact of noises. How do motion. At-sea experiments must be different sources interact and affect species? multiplied to determine thresholds of To answer this question, we need to exposure duration, frequency, amplitude, understand how often a given habitat is and so forth. Given the experimental results exposed to each sound, to identify the effect already obtained, we must also inquire into of each separate sound, and to analyze the the long-term impact of noise on interactions of effects. Cumulative effects on invertebrates that cannot move away from one given species are difficult to quantify. sound and are therefore also likely to suffer Evaluating the effects on populations and directly from noise pollution. then on ecosystems is a challenge for future research. We already know  Fish about different risks for What do we know in this “At the end of the day, we ecosystems, from sequential 1 regard about fish? Does noise want to really find out what is megafaunal collapses to going on and have sensible pollution affect them, or are trophic cascade effects and threshold. We have to discuss they protected from its tipping points. long-term consequences of effects? There is less scientific the behavior changes”. (Frank Sequential megafaunal knowledge about fish than Thomsen, Workshop on collapse about mammals, but the Impact, 10th of March, 2016) experiments that have been First of all, the pressure on conducted reached whales constitutes a major disquieting conclusions. There have been concern. The decline of big studies on behavior response in the open whales due to industrial whale fishing has ocean, but more lab work is needed. A been shown to provoke a sequential recent survey demonstrated that marine megafaunal collapse, as killer whales move renewable energy construction sound from feeding on whales, to seals, sea lions affects migratory fish routes (, Bartlett, & and sea otters (Springer et al., 2003). Each Thomsen, 2012). It also suggests that when population sequentially collapsed due to fish are close to construction sites, they past industrial whaling. Effects of marine display behavior responses to noise a few sound on large mammals can therefore have kilometers away and may be physiologically more far reaching consequences than now affected. imagined. Research also shows that sound pressure variations affect swim bladder fish such as the Atlantic cod (Andersson, 2011). Interestingly, it also suggests that fish developed in a very different soundscape 1 Relative to the megafauna, i.e. large animals of a and have not adapted to a noisier ocean. given region or habitat.

20 Trophic cascade effects What is sound and how to measure it In addition, there can be trophic cascade in ocean? effects on ecosystems (Estes, 2016). As was shown in the case of sea otters and kelp Definition of underwater noise pollution forests, the disappearance or decline of a Sound is characterized by: keystone predator past a certain point can result in the collapse of a whole ecosystem  A source: type of acoustic emission, its (Estes, Tinker, Williams, & Doak, 1998). The nature and characteristics combination of sound with the  Propagation: how sound propagates in a consequences of and other given zone, and how it cumulates with anthropic impacts could heighten the other sources probability of an ecosystem’s  A receptor: the affected organism collapse. Sound travels underwater approximately four times Tipping points and marine sound “Cetaceans can adapt more faster than in the air, and easily. But the adaptation to Finally, another type of risk with less attenuation. In noise may not be a . If the oceans, multiple threatens ecosystems. they change their Increasing human activities can reproduction sound, is that parameters can affect the lead ecosystems to undergo a enough? They try to change emissions received by major shift in their composition their sounds, but underwater marine fauna. The source (fauna, flora, etc.), known as noise pollution can still be itself will variably impact “tipping point” (Hicks, Crowder, physiologically impacting receptors based on factors Graham, Kittinger, & Cornu, them. The plasticity of such as its frequency (high 2016). In that perspective, mammals’ behaviors is not a or low), duration, and understanding the whole scope satisfying answer. You cannot intensity. The distance of the impact of human activities say that it solves the between source and on ecosystems appears essential problem”. (Patrick Miller, receptor also plays a role, th for ocean management. That Workshop on Impact, 10 of and the environment’s includes the effects of marine March, 2016) characteristics with sound. respect to , temperature, depth, sea It is essential to anticipate bed and surface properties will affect sound tipping points before they occur, especially propagation. What makes sound by identifying factors that may aggravate phenomena particularly complicated is that human pressures (Hicks et al., 2016). New sound does not propagate uniformly in oil and gas marine exploration technologies, water. High frequency emissions seem to which generate considerable noise decline faster than low frequency ones. For pollution, could constitute such a factor. For instance a 100Hz acoustic emission can be instance, the seismic air gun was a huge detectable hundreds of kilometers away improvement over what was used before. It whereas a 100kHz will stop after a few constituted a technological advance, and kilometers (Marine Mammal Commission, was widely adopted; it is nonetheless far 2007). Finally, in the ocean, sound can affect from innocuous, and can play a role in animals along the three dimensions, driving the ecosystem to a tipping point. including depth, which results in a complex Establishing such tipping points with regard three-dimensional soundscape. to noise pollution requires in the first place measuring sound and its impacts on fauna. In the Descriptor 11 of the Marine Strategy Framework Directive, sound is characterized as: 1. Impulsive sound: loud, low and mid frequency sounds used for seismic surveys, piling, , explosions 2. Continuous low frequency sound: ambient noise like commercial shipping

21 Natural oceanic sound sources include European project. The last stage consists in earthquakes, waves, rainfall, animal noises, analyzing the statistical noise maps through and so forth. Anthropogenic activities such bioacoustics criteria for the marine species as shipping, seismic surveys, research to be protected in the area of interest, as activities, sonar, or exploitation of resources was done in the AQUO Project. in the sea floor constitute sources of more or less strong noise. Even though measuring The above general considerations on underwater noise pollution is difficult, the measurement procedures should apply in evidence shows that it has greatly increased particular for the three main industries or in the past sixty years. activities causing underwater noise, i.e. shipping, oil and gas, and marine Indeed, developments such as the growing renewables. For that purpose, it is number of offshore extraction sites, the indispensable to develop standardized steady growth of worldwide maritime traffic methods, describe methods for measuring and cruising ships, and the emergence of the level of various anthropogenic noise Renewable Marine Energies (RME), have sources (e.g. ships, underwater air guns and drastically increased the anthropic pile driving), and characterize underwater pressures linked to noise. sound in a given maritime area. The harmonization of the measurement Effective monitoring and modeling are methods used by different stakeholders is a needed to gather and analyze underwater primary condition for comparing data noise data. The challenge is to collect across locations and assessing its evolution accurate information from extreme over time. It is therefore essential to locations, as well as to obtain information at encourage the recently begun low cost, and finally to identify temporal standardization effort in underwater and spatial variability. acoustics at the international level. Measuring sound to better evaluate, Marine renewables that use pile driving monitor and manage impacts during the construction phase constitute A hydrophone placed underwater in the another major source of high noise ocean measures an intricate chorus of pollution. The diversity of sources highlights sounds that mix geophony (natural noises) the importance of measuring underwater and biophony (sound emitted by living noise and of standardizing noise organisms), with the anthropogenic noise measurement across industries. we are interested in. Measurements include  Shipping everything. In the first place, therefore, specific signal processing is required in Shipping is a major noise-generating order to differentiate the sources of noise. industry. Two European research consortia The second step consists of mapping the have investigated this topic: AQUO (Achieve noise in the maritime area of interest, taking QUieter Ocean) and SONIC (Suppression Of into account the fact there may be strong underwater Noise Induced by Cavitation). variations from one location to another For a given vessel, two main categories are within the same zone. Since the long-term generally acknowledged as the main sources deployment of a large quantity of of underwater noise: propeller/thruster and underwater sensors to establish these noise machinery. Propeller or thruster noise maps is not feasible, one must use comes mainly from cavitation. Within techniques based on numerical methods, defined conditions, when the propeller calibrated on the basis of in-situ rotates, localized pressure changes on the experimental data. Post-processing includes propeller blades create bubbles that may performing time-domain statistics. This not only damage propeller blade surfaces, procedure, with which the environmental but also induce underwater noise. Studies status for underwater noise in a specific on efficiency improvement often lead to maritime area can be assessed, has been design and operate close to cavitating demonstrated recently in the BIAS conditions. Both approaches (gain on

22 efficiency and reduction of underwater the oil and gas industry, from airgun uses to noise) are to be addressed simultaneously. airborne sound pollution. For instance, an overflying aircraft generates underwater Machinery noise and vibrations are also noise pollution by transmission through the significant contributors to underwater interface between air and water. A major pollution. The efforts that have already been source of noise pollution, common to other made to cut them down so as to increase industries such as marine renewables long-term machine reliability and comfort (offshore wind farms for instance) is on board tend also to reduce the noise construction (pile driving, vibration, general footprint of ships significantly. impact). Underwater noise from impact pile Since and sea conditions can affect driving is impulsive in nature. It is believed signals of hydrophones, measuring that most of the noise created by an oil and underwater noise footprint constitutes a gas platform does not come only from the challenge. It is therefore necessary to take operations (drilling or production), but also that into account and to combine from sources located on the platform above measurement and modeling. Such approach water, such as power generation (Spence et raises methodological issues concerning, for al., 2007, p. 26). instance, decisions about how to quantify The use of explosives also has potential the noise contribution of a propeller. harmful impacts on animals within its range. Determining shipping noise footprint in an Explosives are employed for several area requires various kinds of information purposes in the oil and gas industry, for about a ship’s location and characteristics instance to decommission offshore (e.g. vessel type, size, speed, as well as structures, remove obstacles, or seismic propulsor type and actual loading). exploration. In contrast to low explosives, Presently, AIS gives a ship’s location, but high explosives have fast rates of detonation otherwise limited information; and some and thus create a sharp pressure impulse, a classification societies provide data on shock wave that travels in all directions; the individual vessels. oscillations of the gaseous bubble left On the whole, detailed underwater noise behind by a detonation in turn generates a measurements on individual vessels remain series of pulses (Wyatt, 2008). insufficient. A larger database of reliable In this industry, when the energy produced measurements of radiated noise from a is exactly known, it is relatively easy to variety of vessels of different types and sizes characterize noise sources. The task is more operating at different speeds would be difficult in complex environments, where needed to improve the models representing many sources of noise coexist and there is ships as underwater noise sources. uncertainty about energy production.

 Industrial activity, including Oil and  Diversity of methods and the need for gas standardization Along with naval sonar systems, the oil and Measurement involves different steps, gas industry is one of the main sources of including deploying sensors, pre-processing underwater noise pollution. At the data sets, processing signals, aggregating international level, much of the data on oil data, specifying format for data integration and gas noise measurement results from the into models, and more. These steps have to Exploration and Production Marine Sound be standardized for measurements to be 2 and Life Joint Industry Programme . actually commensurable. Reviews of existing papers and literature produced a first classification of sounds in Establishing the same sound pressure level (SPL) at a given reference distance of the source (typically 1m) is a key step toward 2 The Joint Industry Programme, or JIP, was formed in developing standardized measurement 2005 by the Oil and Gas E&P industry to support methods. research on the effect of sound on marine life generated the industry’s activities.

23 The international standardization process A comprehensive approach to has already started. A working group at ISO solutions has been elaborating normative documents, one of which was published recently and What is already known about underwater others are pending. Covering the entire noise pollution depicts a dreadful situation. topic will nevertheless take long, beyond However, solutions exist – though they 2020. Member states need to work together obviously have a cost. To reduce acoustic and support development or pollution in the ocean, two options are implementation of standards for: possible and could be combined: deploying existing innovations, and changing actors’  Terminology behaviors. One of the main obstacles is cost:  Modeling we have to find a way to deal with the issue  Measurement of noise without creating too heavy a  Long-term monitoring burden on such essential economic activities Future programs should help Member as fishing, shipping, mining and oil States and Regional Sea Conventions exploration, or the exploitation of implement operational monitoring renewable marine energies. programs. Assessment and regulation must There exist many diverse and innovative also be considered at a sea regional basis. solutions to reduce, mitigate, manage and  Noise footprint and mapping monitor marine sound. They range from technical mitigation innovations in pile Based on these different criteria it is driving or cavitation, to managerial tools possible to define the noise footprint of based on sound mapping monitoring human activities, especially by combining combined with suitable indicators and real local measurements and statistical time monitoring tools. The overall costs of modeling. implementing solutions based on new There are many different sources of sound: design requirements or special noise from nature, from animals, from ships, from mitigation devices remain a real issue with extraction activities, renewables regard to both financial and competitive infrastructures, etc. These have been advantages costs. Deployment also raises analyzed, but one of the main conclusions the problem of regulations and incentive. today is that much more information is still Technical solutions needed. There are multiple characteristics to take into account, but we cannot possibly Technical solutions exist in many sectors, have models for every single type of ship, or from shipping to oil and gas or marine even for all types of activities. Yet everyone renewable. Some seek to reduce the sound wants more information, whether it is from generated by ships or pile driving. Such the AIS, from the naval industry, or from innovations include air bubble curtains to self-measuring ships. mitigate the propagation of underwater sounds, which are used mostly for pile Mapping soundscapes is essential to driving, one of the main source of noise in evaluate impact on whole habitats and marine renewable industry. In shipping, ecosystems, taking into account that there is reducing cavitation drastically reduces never only one sound source, and that sounds. The cost impact can be moderate if multiple sources combine, interact and taken into account in when designing the evolve differently over time and space boat. depending on water characteristics such as salinity and temperature, as well as on It can also be envisaged to replace a vessel’s human activities (level of traffic). propeller by a better one. Solutions dedicated to machinery are also likely to dim underwater-radiated noise and improve comfort on board.

24 Interesting alternative techniques are those fact that they concern only marine that can reduce sound while improving mammals and not fishes or invertebrates. effectiveness or performance. For instance, certain shipping paints reduce drag by There is therefore no one-size-fits-all enhancing hydrodynamics, and thereby solution. It is necessary to develop and better fuel efficiency or have antifouling deploy innovations, and to combine them in effects; as a consequence, they may also order to reduce sound at the source or reduce ships’sound radiation. mitigate its impacts on marine fauna. The IOGP E&P Marine Sound and Life JIP Managing anthropic sound effects on report proposes diverse methods as animals potential seismic source treatment, from air So far most noise management devices have gun silencers to LACS systems (piston-type targeted marine mammals. For instance, source excited via internal combustion) Marine Mammal Observers (MMO) are one (Spence et al., 2007). Marine Vibroseis of the main managerial tools used during methods may also work as a sound- noise-producing activities, such as the reduction system. Marine Vibroseis consists construction of a platform. Protocols using in the suppression of unwanted higher- MMO are generally deemed useful only in frequency components, which is expected to specific contexts; the tool has many have less environmental impact than limitations regarding distance of visibility, surveys using airgun arrays (LGL and MAI, night-work, submersed passing animals, and 2011). However, there are no direct studies other situations and phenomena. More of the biological effects of Marine Vibroseis precise decision-making tools are therefore operations. Overall, alternative techniques required, especially to take into account in the oil and gas industry still have to be effects on a broader range of marine life commercially tested and need to move forms. beyond the “proof-of-concept” stage. Raw sound data can be used to build Passive Acoustic Monitoring Systems soundscape mapping of the marine (PAMS) seem to be attracting consensus, environment. Such maps can become a except perhaps in some areas where specific useful decision making tool in a context of species cannot be detected (a silent whale high uncertainty. However, while cannot be detected through passive visualization is helpful, it is not by itself a acoustics). PAMS refer to using basis for making decisions, and must be hydrophones, i.e. underwater microphones, combined with a quantification of noise to detect and monitor animals, usually levels and thresholds. For instance, showing vocalizing mammals. In contrast to animal the evolution of soundscapes in relation to scarer systems, sonars or pingers, such ship speed reduction in a given area would systems introduce no energy in the help find the right thresholds for environment, but they are limited by the transportation.

25 Figure 1: Constitution of soundscape maps (source: Peter Sigray, BIAS Team, "Baltic Information on the Acoustic Soundscape", Workshop 2, 02/09/16)

Thus, the BIAS project measured shipping Such tools allow managers to see the effects noise for one year in 38 locations on the of increased or lower shipping noise Baltic Sea. A large amount of data was pollution instantly. produced, allowing soundscapes to be mapped (see Figure 1). The project resulted Enhancing, developing and generalizing in the development of a GIS-based planning mapping tools to other regions and all forms tool using in-situ observations and of underwater noise pollution and species modeling, and resulting in soundscape would certainly facilitate decision-making mappings combined with maps of marine processes. This has been the goal-based life. It thus became possible to focus on approach of research consortia AQUO and zones where cod is mating and to see how SONIC, whose common guidelines are the cod area is affected by continuous zones. available online.

Figure 2: Soundscape in the Baltic Sea (source: Peter Sigray, BIAS Team, "Baltic Information on the Acoustic Soundscape", Workshop 2, 02/09/16)

26 Changing behaviors: regulation, financial building common approaches and fostering incentives and nudge cooperation at the EU and regional level. Most industries have already developed or While EU and US regulations have tackled employ technologies to reduce sound some areas of marine sound, financial emissions or mitigate their effects. Shipping incentives could prove useful with regard to appears as a very innovative sector, but commercial fleets, as it is sometimes done in measures are still limited, largely due to the car industry when bonuses are used to implementation costs; these could be encourage buying new cars. Nudge reduced if design were improved at an early strategies are also to be explored as ways to stage of ship design. In renewable marine change behaviors, for instance by energies, innovations are already being encouraging the use of antifouling paints implemented; feedback may give rise to that also reduce noise. further innovations. Regulation, especially in Germany and the Netherlands, seems to One could imagine a scenario with two have been a strong driver in this process. different kinds of zones: It appears that regulation does not follow Protected zones, such as marine protected innovation close enough, and that it areas or opportunity sites, that is to say key therefore does not encourage enough the that are still free from noise enforcement of underwater noise pollution. As research already shows, it limitations. This might be linked to a lack of would be relatively easy to keep these zones quantitative indicators and clear targets for quiet (Williams, Erbe, Ashe, & Clark, 2015). environmental impact and surveillance, and Zones with high maritime traffic and probably reflects the difficulty, mentioned industrial activities: making these noisy above, of obtaining reliable measurement. habitats quiet will be more complicated. For The European Commission and the United these zones, and for other areas where such States have already started to address the activities are carried out, problem of marine sound. In the EU, the will have to be based on population or Marine Directive provides a legal habitat. Moreover, the development of framework for protecting the seas. Its adequate mitigation or monitoring systems overarching goal is to achieve by 2020 a and instruments will require differentiating “good environmental status” for EU’s Marine among species and taking into account their . This label describes “the particular behavioral responses. environmental status of marine waters One should reach out to both regulators and where these provide ecologically diverse end-users (ship owners, oil and gas and dynamic oceans and seas which are companies) to get them to collect data and clean, healthy and productive” (Marine generalize best practices, including Strategy Framework Directive, 2008 Art. technical innovations when they are cost- 3(5)). efficient. Collaborations between industry The pursuit of such goal has four main and public research will in this regard prove implications. First, it requires protecting crucial for developing appropriate marine ecosystems, that is to say, innovations, and for creating a framework developing clean, healthy, productive seas for monitoring and enforcing, i.e. an that are fully functioning and resilient to adequate system of governance. human-induced environmental impacts. Second, it implies preventing the decline of Governance Framework biodiversity and guaranteeing that human- During the series of workshops on marine related substances and energy do not sound organized by the Observatory for pollute the oceans. Third, it necessitates Responsible Innovation, the governance ensuring sustainable uses of EU marine mechanisms that will help articulate resources and thus their continuity for regional regulations into a more global future generations. And finally, it calls for

27 framework for marine sound emerged as a as oil and gas (via the Exploration & challenge of global scope. Production Sound and Marine Life Joint Industry Programme), from research Addressing underwater noise pollution consortia (AQUO, SONIC), research centers, raises three coordination issues. First, and other relevant institutions. It could also coordinating and connecting data at the centralize new data-collection initiatives. global scale, i.e. integrating and taking The World Ocean Council seeks to launch a advantage of big data. Second, coordinating cross-industry initiative of that sort (Smart knowledge about existing solutions across Ocean/Smart Industries), and the platform sectors. And finally, coordinating dialogues proposed here could provide end-users with among regulators, economic actors and such data. experts. In this section, we propose a governance framework to help integrate The objective would be to centralize data research efforts, industrial activity, and produced by currently unrelated human decision making. activities (from earth observations to shipping) in order to address the questions Underwater Noise Data platform of cumulative effects and tipping points. We identified the need for a collective data Global governance device platform that would process and standardize sound data and provide it to We also argue that more coordination is end-users. Two paths seem viable: needed among actors. Conservation organizations and the business community creating a new data platform dedicated to should work together to design practices of sound related data drawn both from human environmental management that take both activities and from animal and environment resource limitation and economic interests observations; into account. The governance of using the existing data platform of the heterogeneous organizations, with different Copernicus Marine Environment Monitoring agendas and interests, could take the form Service (CMEMS), which is a system for of a multi-stakeholder meta-organization monitoring the Earth. CMEMS consists in a (Berkowitz, Bucheli, & Dumez, 2016). Meta- complex set of systems that collect data organizations have been shown to facilitate from multiple sources (in-situ observations, dialogue among different actors, such as satellites, earth observations, etc.) and then regulators, marine industries and research processes and standardizes it so as to labs, and to facilitate the transfer of provide it to end-users (Berkowitz & knowledge and innovation across sectors. Herlem, 2015). Due to large regional differences, managing The goal of such a platform is to provide an underwater noise challenges requires a inter-organizational space where different regional approach. For that reason we sectors and organizations (scientific or suggest the development of a global multi- economic for instance) can bring data stakeholder cross-sectoral meta- together to build a large-scale information organization, with regional branches relying system on marine sound. The platform on UNEP regional sea program. would also offer a networking space where However, if the governance device is to be research projects and grant applications efficient and attractive for every could be developed. stakeholder, it would also have to be cost- The workshops made clear that facing efficient and flexible, two characteristic underwater noise requires more features of meta-organizations. Such a interdisciplinary collaboration; the above- governance device would foster self- mentioned platform would provide regulation, enabling actors to collectively opportunities for it. In an initial stage, the elaborate the rules best suited to each platform could retrieve existing open data context, and to benefit from the strength of on underwater noise from industries such consensus-decision making processes.

28 Conclusion cumulatively significant. For all these reasons, there is a strong demand for an Even in the absence of a complete scientific international cooperation that could take picture of the range of its harmful effects, the form of a noise-dedicated multi- underwater noise pollution has emerged as stakeholder meta-organization bringing a major environmental issue. Combined together regulators, industries, experts and with other pressures, such as plastic scientists. discharge, acidification and overfishing, underwater noise pollution may contribute References to serious regime shifts and ecosystems collapses. Andersson, M. H. (2011). Offshore wind farms- ecological effects of noise and habitat What are the main challenges? Although alteration on fish (Doctoral thesis). Stockholm progress has been made, more University, Faculty of Science, Department of understanding is required in three main Zoology. Retrieved from http://www.diva- domains. First of all, we need more data on portal.org/smash/record.jsf?pid=diva2:391860 identification and characterization André, M., Solé, M., Lenoir, M., Durfort, M., Quero, (types of anthropogenic sound introduced C., Mas, A., … others. (2011). Low-frequency into the marine environment and their key sounds induce acoustic trauma in features). Second, we need more knowledge cephalopods. Frontiers in Ecology and the on the type of exposure (what are the Environment, 9(9), 489–493. patterns of habitat and sound distribution? Beltrán, P., Díaz, J. I., & Salinas, R. (2012). what are the key areas of overlap between Achievement of the new underwater- marine fauna and sound energy?). And radiated noise requirements by the Spanish finally, we need to better evaluate the shipbuilding industry. The FRV" Ramón Margalef. Proceedings of The 11th POMA-ECUA, response to sound of marine mammals and 17. Retrieved from other animals. Difficulties nonetheless arise. The development and deployment of http://www.ieo.es/documents/10640/3726 0/Margalef_ecua2012_tsi.pdf/5ffe2d54-d3ac- sensors is expensive, and their reliability 4aef-8e1a-991b18f9a9ff can be questioned. They also raise energy efficiency issues. Innovative methodologies Berkowitz, H., Bucheli, M., & Dumez, H. (2016). such as the use of passive acoustics could be Collective CSR strategy and the role of meta- organizations: a case study of the oil and gas an alternative for certain monitoring industry. Journal of Business Ethics, Online activities where sensors may replace radars. First. Combining measurement and modeling, in Berkowitz, H., & Herlem, K. (2015). Open data predictive models such as those developed governance in a big data context: Evidence in shipping is a fruitful alternative that from the case of . EGOS, 2015 should be developed and generalized across 31st conference (Athens). industries. Curé, C., Antunes, R., Samarra, F., Alves, A. C., There are also management challenges to be Visser, F., Kvadsheim, P. H., & Miller, P. J. faced, from developing and deploying (2012). Pilot whales attracted to killer whale decision-making tools to encouraging sounds: acoustically-mediated interspecific interactions in Cetaceans. PLoS One, 7(12), technical and technological innovations e52201. diffusion across industries. Current regulation requirements for sound Estes, J. A. (2016). Serendipity: An Ecologist’s Quest to Understand Nature. Oakland, producers are inconsistent, and current California: University of California Press. laws do not address specifically the noise produced by different industries such as oil Estes, J. A., Tinker, M. T., Williams, T. M., & Doak, D. F. (1998). Killer whale predation on sea & gas, commercial fisheries and aquaculture otters linking oceanic and nearshore industries. The monitoring of effects and the ecosystems. Science, 282(5388), 473–476. control over compliance with mitigation measures are inadequate or even non- Geotimes. (2003, January). Whales beach seismic research. Retrieved from existing. There is no accounting for individually insignificant effects that may be http://www.geotimes.org/jan03/NN_whales.html

29 Gill, A. B., Bartlett, M., & Thomsen, F. (2012). Nedelec, S. L., Campbell, J., Radford, A. N., Potential interactions between diadromous Simpson, S. D., & Merchant, N. D. (2016). fishes of UK conservation importance and the Particle motion: the missing link in electromagnetic fields and subsea noise from underwater acoustic ecology. Methods in marine renewable energy developments. Ecology and Evolution, 7(7), 836–842. Journal of Fish Biology, 81(2), 664–695. http://doi.org/10.1111/2041-210X.12544 Hicks, C. C., Crowder, L. B., Graham, N. A., Romano, T. A., Keogh, M. J., Kelly, C., Feng, P., Kittinger, J. N., & Cornu, E. L. (2016). Social Berk, L., Schlundt, C. E., … Finneran, J. J. drivers forewarn of marine regime shifts. (2004). Anthropogenic sound and marine Frontiers in Ecology and the Environment, mammal health: measures of the nervous and 14(5), 252–260. immune systems before and after intense LGL and MAI. (2011). Environmental assessment sound exposure. Canadian Journal of Fisheries of marine vibroseis. LGL Rep. TA4604-1; JIP and Aquatic Sciences, 61(7), 1124–1134. contract 22 07-12. Rep. from LGL Ltd., Spence, J., Fischer, R., Bahtiarian, M., Boroditsky, environ. res. assoc., King City, Ont., Canada, L., Jones, N., & Dempsey, R. (2007). Review of and Marine Acoustics Inc., Arlington, VA, existing and future potential treatments for U.S.A., for Joint Industry Programme, E&P reducing underwater sound from O&G Sound and Marine Life, Intern. Assoc. of Oil & industry activities. Joint Industry Programme Gas Producers, London, U.K. on E&P Sound and Marine Life. Marine Mammal Commission. (2007). Marine Springer, A. M., Estes, J. A., Van Vliet, G. B., Mammals and Noise: A Sound Approach to Williams, T. M., Doak, D. F., Danner, E. M., … Research And Management. A Report to Pfister, B. (2003). Sequential megafaunal Congress from the Marine Mammal collapse in the North Pacific Ocean: An Commission. ongoing legacy of industrial whaling? Marine Strategy Framework Directive. (2008). Proceedings of the National Academy of Directive 2008/56/EC of the European Sciences, 100(21), 12223–12228. Parliament and of the Council. Official Journal Wartzok, D., & Ketten, D. R. (1999). Marine of the European Union. Retrieved from mammal sensory systems. Biology of Marine http://www.fishinmed.eu/wp- Mammals, 1, 117. content/uploads/2015/07/DIRECTIVE- Williams, R., Erbe, C., Ashe, E., & Clark, C. W. 200856EC-of-17-June-2008.pdf (2015). Quiet(er) marine protected areas. Miller, P. J., Antunes, R. N., Wensveen, P. J., Marine Pollution Bulletin, 100(1), 154–161. Samarra, F. I., Alves, A. C., Tyack, P. L., … http://doi.org/10.1016/j.marpolbul.2015.09.012 others. (2014). Dose-response relationships Wyatt, R. (2008). Review of existing data on for the onset of avoidance of sonar by free- underwater sounds produced by the O&G ranging killer whales. The Journal of the industry. (No. Issue 1). Joint Industry Acoustical Society of America, 135(2), 975– Programme on E&P Sound and Marine Life. 993.

30 Scientific, technical and managerial contributions

31

CONTRASTING WHALE BEHAVIORAL RESPONSES TO ANTHROPOGENIC NOISE AND PREDATOR PRESENTATIONS TO ASSESS BIOLOGICAL SIGNIFICANCE

Charlotte Curé(1) & Patrick Miller(2) (1) Researcher at Cerema, Dter Est, Laboratory of Strasbourg, Acoustics Group, Strasbourg, France (2) Professor at University of St-Andrews, SMRU, St-Andrews, UK

Introduction given anthropogenic noise on the behavior of free-ranging animals has been based on Underwater man-made noise has been the following: first, to characterize the recognized worldwide as a form of acoustic normal behavioral pattern of animals (i.e. pollution for marine organisms, impacting before any sound exposure) called “pre- both their physiology (e.g. hearing exposure baseline behavior”; second, to impairment, stress) and behavior (e.g. expose the subject whale to a controlled reduction of foraging effort, avoidance) dose of an acoustic stimulus and assess the (Southall et al. 2007). Marine mammals are behavioral changes in response to the considered a sentinel species to study stimulus. To do so, it is needed to choose effects of anthropogenic noise because i) and measure specific behavioral metrics they rely primary upon the acoustic channel that are relevant to the studied to communicate, to search for food, to behavioral/functional context (e.g. a proxy reproduce and to get information from their for energy intake in a context of feeding). If environment, and ii) they can vocalize and comparing the behavior between baseline hear within the frequency range generated and sound exposure periods provides by anthropogenic sound sources (Nowacek insights into the behavioral changes induced et al. 2007). by the anthropogenic noise, the interpretation and biological significance of Behavioral changes can have impacts on those responses can still be difficult to fitness of individuals that might further lead explain. A third ingredient can improve the to consequences at the population level recipe: comparing behavioral responses to (New et al. 2014). For instance, a repeated the anthropogenic stimulus to a reference and/or long-term alteration of whale model indicating how animals react when foraging behavior in response to a given they face a natural biological high-level disturbance stimulus might lead the disturbance stimulus (Curé et al. 2013, unhealthy animal to be more likely to die, or 2015). Reactions to an immediate predation to not breed in a year it might otherwise risk can be such a good model (Frid & Dill have produced offspring. The development 2002). Indeed, predator presence is a of new technologies such as multi-sensor natural acute threat and is probably the tags that record different behavioral metrics highest level of disturbance animals can (e.g. depth, acoustic recordings, heading) meet in natural conditions since it can lead has provided the possibility to measure the for the animal prey to die. We expect that behavior of free-ranging individual animals animal prey have evolved adaptive anti- even the ones living under the sea surface predator response strategies that are like cetaceans (Johnson and Tyack 2003). biologically costly (altering fitness Since then, it became possible to investigate enhancing activities such as foraging), but the behavioral effects of anthropogenic that these responses had been selected noise on cetaceans by conducting controlled through evolution because leading to the sound exposures, and quantifying the corresponding benefit of increased behavioral changes of the exposed tagged probability of survival (Lima & Dill 1990). animals. Therefore, we expect anti-predator The basic recipe to experimentally behaviors to be strong, clear, with a great investigate potential disturbance effects of a potential to impact fitness of animals, and so

33 that they could be used as a ‘yardstick’ to for at least 10min by a source towed by the assess the relative level of disturbance research vessel and approaching the tagged induced by anthropogenic stimuli. animal. A no-sonar control exposure was also conducted to separate effects of sonar The aim of this review paper was to from effects of the approaching vessel and illustrate such approach by investigating consisted of a silent approach of the source potential disturbance effects of naval sonar vessel in a similar way as for the sonar (3S project, Miller et al. 2012; Sivle et al. exposure but with no sonar transmission. 2015) on the foraging behavior of two cetacean species in their feeding ground off Killer whale playbacks the North Atlantic: the sperm whale (Physeter macrocephalus) and the Natural sound playbacks were performed humpback whale (Megaptera novaeangliae). from a dedicated motor boat launched from Both species can be predated upon by the the research vessel. Sounds were played Killer whale (Orcinus orca) from which they back at roughly 800m from the tagged can eavesdrop on calls allowing them to whale using a player and amplifier detect predator presence and to adopt an connected to a Lubell speaker deployed in optimal strategy to get a chance to avoid the water. In order to induce anti-predator predation (Curé et al. 2013, 2015). responses, we aimed at simulating predator Therefore, sonar exposure and predator presence as much naturally as possible. presentation were conducted and the Since killer whales are highly vocal species, measured behavioral responses of tagged we decided to simulate their presence by whales were relatively compared to each playing natural sequences of previously other in order to index response to sonar to recorded mammal-feeding killer whale the expected high level of disturbance sounds (KW stimulus). We played also a (template) in response to the predator. broadband noise (CTRL stimulus) as a negative control to ensure animals Methods specifically respond to the killer whale sounds and not to any sound generated by General protocol the playback system. Both playback stimuli had a frequency band of 0.5–20 kHz, an Experiments were conducted at summer average rms source level of 150 dB re 1µPa time on sperm whales in 2008, 2009 and m and lasted 15 min duration. 2010 and in humpback whales in 2011 and 2012. Field work was conducted aboard a Measure of the behavioral response research vessel in the Norwegian waters. Briefly, the protocol comprised the Since both species were in a context of following phases: 1) a tagging phase where foraging, we focused on investigating a a small motor boat was launched from the potential alteration of whale feeding research vessel to attach a tag (DTAG, behavior in response to the sound Johnson and Tyack 2003) on the animal by exposures. Sperm whales perform long deep the mean of suction cups, 2) Baseline foraging dives while producing loud behavior data collection that started after at echolocation clicks to localize their prey and least 1h of recovery post-tagging period, 3) emit buzzes once the prey is about to be Sound and control exposures, 4) captured. Humpbacks’ lunge-feeding is Detachment and recovery of the DTAG characterized by a strong increase of speed (programmed release). Full protocols are before engulfing a large volume of prey- described in Miller et al. 2012, Sivle et al. laden water followed by a decrease of 2015, and in Curé et al. 2012, 2013, 2015. speed, which can be identified by a specific acoustic signature of the flow noise Sonar exposures recorded on the DTAG (Sivle et al. 2015). To contrast the changes of foraging behavior to Both species were tested with a hyperbolic naval sonar to the anti-predator template, upsweep sonar between 1 and 2 kHz we focused on the production of regular (maximum source level of 214 dB re 1µPa clicks and buzzes (foraging sounds) while m), and generated at a rate of 1s every 20 s

34 conducting deep foraging dives (depth >100 production of acoustic foraging cues) was m) for the sperm whale, and on the observed in response to the no-sonar occurrence of lunge events during the control and to the CTRL playback. feeding dives (depth >10 m) for the humpback whale. Foraging cues (regular Discussion clicks and buzzes for sperm whales, lunge events for humpbacks) were identified on Whales ceased feeding in response to the the spectrogram of the acoustic recording predator presentation. As expected, the made by the hydrophones of the DTAG. We responses were strong, clear and highly used the depth sensor of the tags to consistent among individuals within species investigate potential changes in max depth and could be used as a behavioral template and dive duration of the foraging dives. of high level behavioral disturbance in order to relatively compare other potential Results disturbance stimuli such as naval sonar exposure. Similar cessation of feeding was Responses to sonar also elicited in response to the 1-2 kHz naval sonar. Three out of 4 sperm whales that were exposed to the 1-2 kHz sonar signal Other behavioral metrics such as social interrupted feeding activity which was behavior and horizontal avoidance could be indicated by a decrease in the production of investigated to build a broader picture of clicking and buzzing as well as a switch to the response and to index level of shallower and shorter dives compared to disturbance for each category of behavioral baseline (Sivle et al. 2012; Isojunno et al. parameter (Curé et al. in press). Moreover, 2016). we know that animal behavioral responses in general may vary according to other In 10 out of 11 sonar trials conducted on the factors such as body condition, gender, age, six humpback whales that were feeding behavioral state (breeding/foraging/ prior to the exposure, all but one induced a migrating), group composition and cessation of feeding which was indicated by environmental factors such as availability of a significant reduction in lunge rate and a refuge, etc (Wartzok et al. 2003; Curé et al. decrease of max depth and dive duration 2015). Therefore, the anti-predator (Figure 1; Sivle et al. 2015; Sivle et al. in template and responses to anthropogenic revision). stimuli must be compared as much as Responses to killer whale playback possible within a similar context. Three out of 4 sperm whales that were The current study has shown that feeding prior to the KW playback stopped behavioral responses to playback of their foraging dive and returned predator sounds can be an effective high- prematurely to the surface. Five out of 5 level disturbance template to assess the humpbacks stopped lunging during the KW biological significance of responses to playback. This result was shown in sperm anthropogenic disturbances. Specifically, we whale by a strong reduction of production of have shown that in the sperm whale and the regular click and buzz together with humpback whale, the disturbance of significantly shorter and shallower dives foraging behavior induced by naval sonar (Curé et al. 2013), and in humpbacks by a may be as severe as the one induced by an cessation of lunging along with shorter and acute predation risk and are therefore shallower dives compared to the period expected to be costly responses. Ultimately, preceding the exposure (Figure 1; Curé et al. the degree to which such responses lead to 2015). declines in health of an individual depend crucially upon how often the animals are Responses to the controls exposed to the disturbance, and their ability to compensate for declines in health from For both species, no alteration of foraging the disturbance (i.e by feeding more). (no change in the or in the

35 Conclusion Tyack PL, Doksæter-Sivle L (2012) The severity of behavioral changes observed Facing the urgent need to quantify and during experimental exposures of killer interpret the effects of anthropogenic noise (Orcinus orca), long-finned pilot on cetaceans, this study provide an (Globicephala melas), and sperm (Physeter interesting approach for guiding predictions macrocephalus) whales to Naval Sonar. of highly sensitive species and for helping in Aquatic Mammals, 38:362-401. interpreting behavioral responses to Miller PJO, Kvadsheim PH, Lam, FPA, Tyack PL, potential disturbance stimuli in order to Curé C, DeRuiter SL, Kleivane L, Sivle further establish well balanced mitigation L, van IJsselmuide SP, Visser F, Wensveen PJ, and management decisions (Frid & Dill von Benda-Beckmann AM, Martin López L, Narazaki T, Hooker SK (2015) First 2002, Sih 2013). indications that northern bottlenose whales are sensitive to behavioural disturbance from References anthropogenic noise. R Soc Open Sci 2(140484):1-11. Curé C, Antunes R, Samarra F, Alves AC, Visser F, Kvadsheim PH, Miller PJO (2012) Pilot New LF, Clark JS, Costa DP, Fleishman E, Hindell whales attracted to killer whale sounds: MA, Klanjscek T, Lussuau D, Kraus S, acoustically-mediated interspecific McMahon CR, Robinson PW, Schick RS, interactions in cetaceans. PLoS ONE Schwarz LK, Simmons SE, Thomas L, Tyack P, 7:e52201. Harwood J (2014) Using short-term measures of behaviour to estimate long-term Curé C, Antunes R, Alves AC, Visser F, Kvadsheim fitness of southern elephant seals. Mar Ecol PH, Miller PJO (2013) Responses of male Prog Ser 496:99-108. sperm whales (Physeter macrocephalus) to killer whale sounds: implications for anti- Nowacek DP, Thorne LH, Johnston DW and PL predator strategies. Sci Rep 3(1579):1–7. Tyack (2007) Responses of cetaceans to anthropogenic noise. Mamm Rev 37:81-115. Curé C, Sivle LD, Visser F, Wensveen PJ, Isojunno S, Harris CM, Kvadsheim PH, Lam FPA, Miller Sih A (2013) Understanding variation in PJO (2015) Predator sound playbacks reveal behavioural responses to human-induced strong avoidance responses in a fight rapid environmental change: a conceptual strategist baleen whale. Mar Ecol Prog Ser overview. Anim Behav 85:1077-1088. 526:267–282. Sivle L, Kvadsheim PH, Fahlman A, Lam F-P, Curé C, Isojunno S, Visser F, Wensveen PJ, Sivle Tyack PL, Miller PJO (2012) Changes in dive LD, Kvadsheim PH, Lam FPA, Miller PJO (in behavior during naval sonar exposure in press to Sci Rep) Biological significance of killer whales, long-finned pilot whales , and sperm whale responses to sonar: comparison sperm whales. Frontiers in physiology with anti-predator responses. 3(400):1-11. Frid A, Dill LM (2002) Human-caused Sivle L, Kvadsheim PH, Curé C, Isojunno S, disturbance stimuli as a form of predation Wensveen PJ, Lam F-P, Visser F, Kleivane, L, risk. Conserv Ecol 6:11-27. Tyack PL, Miller PJO (2015) Severity of behavioural responses of humpback whale, Isojunno S, Curé C, Kvadsheim PH, Lam F-P, minke whale and bottlenose whale to naval Tyack PL, Wensveen P, Miller PJO Sperm sonar. Aquatic Mammals 41(4): 469-502. whales reduce foraging effort during exposure to 1–2 kHz sonar and killer whale Sivle L, Wensveen PJ, Kvadsheim PH, Lam F-P, sounds. Ecol Appl, 26: 77-93. Visser F, Curé C, Harris CM, L, Tyack PL, Miller PJO (in revision to Mar Ecol Prog Ser) Johnson MP, Tyack PL (2003) A digital acoustic Naval sonar disrupts foraging in humpback recording tag for measuring the response of whales. wild marine mammals to sound. IEEE J Oceanic Eng 28: 3-12. Southall BL, Bowles AE, Ellison WT, Finneran JJ, Gentry RL, Greene CR, Kastak D, Ketten DR, Lima SL, Dill LM (1990) Behavioral decisions Miller JH, Nachtigall PE, Richardson WJ, made under the risk of predation: a review Thomas JA, Tyack PL (2007) Marine mammal and prospectus. Can J Zool 68: 619-640. noise-exposure criteria: initial scientific Miller PJO, Kvadsheim PH, Lam, FPA, Wensveen recommendations. Aquatic Mammals 33(4): PJ, Antunes R, Alves AC, Visser F, Kleivane L, 411-521.

36 Wartzok D, Popper AN, Gordon J, Merrill J (2003) mammals to acoustic disturbance. Mar Factors affecting the responses of marine Technol Soc J, 37:6-15.

Figure 1: example of cessation of feeding in the tagged humpback whale mn12_171ab in response to 1-2 kHz sonar (LFAS, delimited with yellow vertical bars) and to killer whale sounds playback (KW, magenta bars). The dive profile is represented along with indication of feeding (lunge) events (red dots). t0: start of exposure

37

HIGH PERFORMANCE MODELING OF THE PROPAGATION OF BIOLOGICAL SOUNDS IN THE OCEAN: NEW NUMERICAL TOOLS IN THE STUDY OF CETACEANS

Dr Julie Patris(1,2,3), Pr Mark Asch(5), Pr Hervé Glotin(1,2,3,8), Dr Dimitri Komatitsch(1,7) Dr Elwin van’t Wout(4), Dr Susannah Buchan(6) & Dr Franck Malige(1) (1) Université d'Aix Marseille / (2) Université de Toulon / (3) LSIS, CNRS / (4) Pontifical Universidad Católica (5) Université de Picardie / (6) COPAS Sur-Austral, Universidad de Concepción / (7) LMA, CNRS, (8) Institut universitaire de France

Introduction In this study, we propose to build a tool for the localization of a sound-emitting whale The conservation of cetaceans has been a with only one hydrophone, which will be a major environmental concern for the last 50 very new and useful system for the years. Indeed, the population of most large community. Our method has been tested whales probably went down to the verge of only on artificial simulation as far, but a run extinction during the XXth century of in-situ observations in January will allow (Handbook of the mammals of the world, vol. us to test it on real data, and to have a 4), due to non-sustainable whaling. Since ground truth validation of our work. then, new dangers are arising for large and small cetaceans, such as the general level of General idea of the method man-made noise in the oceans (see Boyd et al. 2011, for an international quiet ocean A fixed hydrophone is a common tool for experiment). oceanographers and biologists studying whales: it is not expensive, and it allows One of the first and the most difficult task long term survey of acoustical signals. for cetaceans preservation is to estimate However, it has not been possible until now their actual number (see for instance Branch to recover the emitters’ position with only et al., 2004 for the difficulty of estimating one hydrophone. We propose a new idea to whales population). To be able to decide on reach this goal: to use the information we conservation measures, it is most important have concerning the bathymetry, the sound to be able to evaluate their effects, and thus velocity variation, the ground's properties, the potential recovery of the species. etc. The asumption is that the whale's signal will be modified while propagating in the Passive acoustic monitoring has been complex oceanic medium: by reflexions, increasingly used to estimate cetaceans transmissions and refractions. Thus, populations (Mc Donald and Fox, 1999). information about the whale's However, distance evaluation is necessary environnement is “hidden” in the signal that to make population estimation (see distance we receive. If we have a good knowledge of sampling methods, Marques et al. 2013). the velocity changes in the water layer and This is easily done with an array of of the ground (bathymetry, composition), hydrophones, by time delay of arrival we can use this information to locate an computation (Giraudet et al., 2008) or unseen whale. However, we need a very matched-field processing (Kuperman et al., accurate model of sound propagation to be 2004). However, installing an array of able to take advantage of this information in hydrophones means complicated field work the signal, and this is why we decided to that is not always possible. Although it is work with highly sophisticated modern rather common for measures with towed models, available for the whole community. hydrophones, for small cetaceans for instance, it remains difficult for fixed Modeling softwares instruments and large wavelenght measurements. Because the sound is the first way of communication in the ocean, the physics of

39 sound propagation have been intensively The boundary-element method is studied this last 50 years, involving large potentially faster for computing wave scale simulation with different kind of propagation, because only the interfaces methods (Jensen et al., 2011). Most of the and boundaries of homogeneous regions are efforts however have been focused on being discretized. To this end, we are modelling active acoustics, which implies investigating the use the open-source sending an artificial signal and analyse its BEM++ library (Smigaj, 2015), which propagation throught water and (or) provides frequency-domain acoustic ground (oil industry prospection, fisheries models. or military sonars). The most frequently used methods include ray propagation and First tests of the method parabolic methods (Eter, 2012). Also, most methods assume the source of the sound to Our simulation with its first results is be known and then predict the propagation presented on figure 1. We constructed an of the acoustic wave. In this case, we are artificial 2D box representing a plausible interested in finding the location of the underwater environment two kilometers source, given the geometry and the long (figure 1.a, top). recorded sound. For this to be feasible, we We simulated the propagation of a real first need to develop fast and accurate signal of a blue whale (taken from S. Buchan computational methods for wave recording in Corcovado) at low frequency propagation problems based on state-of- (around 20 Hz). This signal do not require the-art techniques such as finite elements too large a computational time. methods (FEM) and boundary elements methods (BEM). Both of this methods The signal propagation is simulated from a present a high degree of accuracy but point E (position of the supposed whale) to require large computing resources. a point R (position of the fixed hydrophone). A simulation is launched to model the The first method that we use for this study propagation of the signal from a grid of 36 is SPECFEM open-source software virtual whale positions towards the (Komatitsch, 1999). SPECFEM was first hydrophone. These positions are sampling developped for the simulation of seismic the water domain, each 200 meters in wave propagation at large scales in full horizontal plane and each 20 meters in the waveforms. The method combines finite vertical plane (assuming the whale normally element methods and spectral elements, emits sounds while it's not more than 100 using a weak formulation of the equation of meters deep, see for instance Stimpert et al. propagation, which is solved on a mesh of 2015). We then perform a correlation hexahedral elements. We are adapting this analysis to find the position witch is best very accurate method to bioacoustical correlated with the signal emitted from signals. FEM methods are rather CPU-time point A position. consuming, so we are limiting our present study to large baleen whales We obtain a robust estimation of the (balaenopteridae) such as blue whales emitter's position if the grid point is (balenopterae musculus) and fin whales sufficiently close to the emitter's position, (b.physalus) that emit low frequency moans around 50 meters or less (depending on the (around 20 Hz) very well adapted to our bathymetry). Since adding virtual grid methods. However, depending on the size of positions to the model is little time the simulation box and with the help of high consuming, we find that putting an array of performance computational resources, in 50m-spaced virtual emitters in our model (a France (Université de Toulon, TGCC France) box corresponding to the local bathymetry) and in Chile (PUC, Santiago), we hope to be should allow us to find the position of the able to extend the method to other species emitter. such as humpback whales (megalopterae However, this is a first test and it should be novaeangliae). completed by ground validation.

40 Field measures and validation passing ship's noise. In this test, we ran our simulation adding a ship passing by, at a To validate our method and extend it to distance of about 300 m of the hydrophone. acoustical surveys in pristine areas of South The noise level of the ship was taken to be America, we are constructing a net of 180 dB ref. 1 µPa, in accordance with acoustical observatories in the coastal areas Richardson et al., 1995 review book, and the of Chile (see fig. 2 and Malige et al. 2016). signal was taken from our own recording of Blue whale sounds are already being a boat and truncated to 30 Hz (numerical recorded in Corcovado gulf to evaluate blue limit of our model). A virtual whale emitting whales communication (see for instance a moan with the same order of magnitude, Buchan et al., 2015). We are using these at 20 Hz, was placed in the model box, at sounds for our first test and adjustments of 500m from the hydrophone, not in a line the method. with the boat. We found that the noise produced by the boat prevented our In addition, we are planning the installation algorithm from recovering the source's of two buoys, one in Magallanes strait in position: in figure 1.b, the correlation southern Patagonia, in collaboration with maxima no longer shows a peak at the Juan Capella and Jorge Gibbon (Universidad corresponding position. de Magallanes), and the other close to Chañaral Island, in the northern part of With low frequency sound such as blue and Chile, in collaboration with Maritza fin whale's moans, the sound in Sepulveda (Universidad de Valparaíso). We the water is about 75 meters. For these long will thus have signals from other baleen , the separation is not whales, such as fin whales (common in sufficient to help the whale in finding the Chañaral) and humpback whales (common range of the source of a sound, but in the Magallanes strait). reverberation on the ground could help it locating its mates, especially in shallow These two buoys will be equipped with a coastal waters. If this is the case, it is very Cetacean research hydrophone and a simple possible that a ship passing will cut off this recording device, designed by DYNI team in position estimation from the whale. Thus, Toulon University and CNRS (LSIS noise caused by ship, even when it's not laboratory). This low-cost recording device sufficient to mask the whole signal from a is designed to stay underwater for long co-species, will make it more difficult for the periods, while recording with programable whale to know where the other whale is, sampling frequency ranging from a few kHz even at a relatively close range (500 to very high frequencies (2MHz maximum meters). sampling frequency). Conclusion In Chañaral, a team of trained biologists from Valparaíso University will measure the We are developping a new tool in a all- whales' positions while the buoy will be inclusive way, from the mathematical recording their songs during the austral modeling to the ground data acquisition, summer. Thus, we will be able to have with the aim of providing a new tool for the ground truth for our position estimation study and preservation of aquatic mammals method, as well as an estamation of ship (see Patris, 2016 for the detailed exposition noise impacts on general acoustical of the goal of this work). The method is behaviour of the whale (study by M. quite new, but has only been tested with Sepulveda). artificial boxes so far. A ground-truth validation will be aquired during austral Ship noises summer. Ship noise interference is also being Along with the final tests of our method, our investigated thanks to our models. In figure team also work on extending the use of high 1.b, we show that source localization can be performance modelling in other contexts of dramatically affected by the presence of a cetacean conservation: we worked on

41 dolphins (inia geofrensis) in Amazonia dimensional seismic wave propagation” (Iquitos, Peru), and we are considering Geophys. J. Int. (1999) 139, 806-822 adapting our model to higher frequency but Kuperman, Bill and Lynch, James “Shallow-Water smaller volumes to study boat noise and Acoustics” October 2004 Physics Today, dolphin acoustics in . 55-61 McDonald, M. A., and Fox, C. G. “Passive acoustic References methods applied to fin whale population estimation,” J. Acoust. Soc. Am. (1999) Branch, Trevor et al. “Evidence for increases for 105, 2643–2651. antartic blue whales based on bayesian modelling” Marine Mammals Science, Malige, F. et al. (2016) “Advanced 20(4):726–754 (October 2004) interdisciplinary bioacoustical analyses for cetacean observatories in Chile and Peru” in Buchan, Susannah, et al. “Seasonal occurrence of 1st Listening for Aquatic Mammals in Latin southeast Pacific blue whale songs in America Workshop held in Natal/RN, Brazil, southern Chile and the eastern tropical from June 21 to 23, 2016. Pacific”, Marine Mammal Science, 31(2): 440-458 (April 2015) Marques, Tiago A. et al. “Estimating animal population density using passive acoustics”, Etter, Paul C. “Advanced applications for Biol. Rev. (2013), 88, pp. 287–309. underwater acoustic modeling”, Advances in Acoustics and Vibration, vol. 2012, Art. ID Patris, J. et al. "High-performance computing for 214839, 28 p. whale sound propagation in South American oceans based on accurate numerical Giraudet, Pascale and Glotin, Hervé “Real-time techniques", in 1st Listening for Aquatic 3D tracking of whales by echo-robust precise Mammals in Latin America Workshop held in TDOA estimates with a widely-spaced Natal/RN, Brazil, from June 21 to 23, 2016. hydrophone array” Applied Acoustics 67 (11), 1106-1117 (2008) Handbook of the Smigaj, W., et al. “Solving boundary integral mammals of the world, vol. 4 , Sea mammals. problems with BEM++” ACM Trans. Math. Lynx Edicions, 2014 Softw. V, N, Article A (2013), 50 p. Jensen, Finn B. et al. “Computationnal ocean Stimpert et al. “Sound production and associated acoustics”, Springer, 2011. behavior of tagged fin whales (Balaenoptera physalus) in the Southern California Bight” Komatitsch D. and Tromp J. “Introduction to the Anim Biotelemetry (2015) 3:23 spectral element method for three-

42 Fig. 1: Model. a. (top) Geometrical representation of the modeled box. R is the position of the receiver (hydrophone on a buoy) E is the position of the virtual whale, and green lines are a virtual grid of possible positions for the whale. b. (left) correlation maxima versus position index. The peak of the correlation maxima points to the position 30, which is indeed the closest point to the virtual whale. c. (right) The same plot but with a ship passing by: the correlation peak is lost in a large bulk corresponding to the noise correlation with itself. In this case, it's not possible to infer the whale's position anymore (see text).

Fig. 2 : map of the acoustic observatories.

43

SURFACE SHIP PASS-BY NOISE FOR SOUND SOURCE IDENTIFICATION

Benoit Oudompheng(1), Barbara Nicolas(2), Arthur Finez(3) & Agnès Gerphagnon(4) (1) PhD student at MicrodB (2012-2015) and Research Engineer at Thales (2015), (2) Research Engineer at GIPSA-Lab / (3) Research Engineer at MicrodB, (4) Project engineer at VIBRATEC

With the advent of environmental criteria and prove the interest of underwater pass- for sound pressure levels radiated by by noise mapping [6]. commercial ships in the coming years, the naval community needs to define standards The first interest of the project was the to measure noise radiated by such craft description of the sources composing the [1][2]. To achieve certification, passing ship acoustic signature of a surface ship. Indeed, noise mapping should be a useful tool to array dimensioning and processing is help the naval industries acoustically design influenced by the acoustic sources of their ships. Indeed, noise mapping makes it interest: frequency content, location, speed. possible to localize the different vehicle The 3 components identified in the acoustic acoustic sources and provides information signature are noises coming from the about their contributions to the global propeller, from its cavitation, and from acoustic pressure level. Compared to global internal machines. The same classification levels, the noise mapping results are of was proposed in the European AQUO interest to focus the noise reduction on the project [7]. The components have different main acoustic contributors. They also give physical origins: hydro-acoustic or vibro- input data quantifying the source power for acoustic, meaning that the surface ship simulation tools and permit the validation of emits close sources with large frequency simulations. bands and tones. Depending on the speed, each component’s contribution to global In aerial environments where standards noise varies. Pass-by analysis with acoustic have been applied for several decades, mapping for different speeds can help to vehicle pass-by noise mapping technologies determine their contribution to global noise have been developed and adapted to the and their evolution with the speed. aeronautic [3], railway [4], and automotive Following this classification, a simulation industries [5]. The publications are tool was developed to synthetize far-field numerous in the literature of these domains noise emission with a few typical surface but are almost non-existent in the ship sources [8]. The tool was used to underwater domain. Results prove the validate the array processing. interest of such procedures whereas they are of high cost. They are carried out in In aerial environments, the pass-by noise parallel to certification when the pass-by mapping task is classically addressed using cost itself is expensive. In this context, the far-field microphone array measurements feasibility of an underwater pass-by with beamforming processing. Due to procedure was interesting to investigate. vehicle movement, some adaptations are Thanks to French DGA support through a needed compared to fixed noise sources to PhD thesis and to RAPID tool, the ARMADA compensate the Doppler Effect and to focus project lead by the French company on the moving vehicle. The literature is less MicrodB (subsidiary of VibraTec), in extensive for the underwater environment partnership with the GIPSA Lab in Grenoble, than the aerial one, with only a few studies was carried out between 2012 and 2016. It conducted on towed-ship models for ended with experimental measurements denoising [9][10]. In the underwater using a scale model of a surface ship towed environment, the signal-to-noise ratio is in a mountain . Results are encouraging poor and hydrophone arrays only contain a few sensors due to their high cost and

45 difficult installation and maintenance. This Whereas beamforming has been improved explains the difficulty of underwater pass- and gives the acoustic hot spots, some of the by noise applications. Indeed, beamforming sources are not separated at low frequency array processing has a poor spatial and large frequency range, or wrong alarms resolution with small arrays and it is not and bad interpretation could be due to low possible to separate two close sources at dynamic range. These artefacts are due to low frequencies. A second issue is the the convolution of the source distribution by dynamic range, which can be only of few the array pattern and additive measurement decibels in noisy environments. This can be noise not included in the source model solved by higher microphone density but which disturbs the beamforming processing. also leads to expensive solutions It is usual to apply deconvolution methods underwater. on beamforming map to solve those issues. A spatial blind beamforming deconvolution For the purpose of surface ship noise was developed during the project using the mapping, linear antennas can give source assumption of sparse sources and the positions along the ship in one dimension. presence of Gaussian noise in the model They form larger arrays with better space [13]. It has proved its robustness against sampling than 2D antennas, but suffer from noise and does not require an accurate their relatively small size and few localization initialization. hydrophones: usual pass-by aerial arrays have over 50 microphones! The adaption of Another main issue in moving-source aerial methodologies with advanced mapping is the knowledge of the trajectory processing improves resolution and of the moving object containing the sources. dynamic range. Indeed, trajectory errors induce localization artefacts in beamforming results, which can The innovation in processing lies in the degrade performances and bias physical passive synthetic aperture array technique source interpretations. A novel method has to improve low-frequency resolution, the been proposed [14] to correct trajectory use of beamforming results to improve mismatches. This method requires first trajectory accuracy and deconvolution localization maps along the trajectory to methods in noisy environments. estimate the trajectory mismatches by Since beamforming suffers from poor spatial intercorrelations between source resolution at low frequencies, a passive localizations. A reference map is then synthetic aperture array technique was defined to estimate a corrected trajectory. proposed to improve the localization The developed methodology was initially resolution for monochromatic sources at validated from simulation and aerial low frequencies, e.g. vehicle mechanical experiments before water experiments. The noise sources [11]. Many passive synthetic good results encouraged a unique pass-by aperture array studies have been reported experiment of a 1:5 scale model of a surface over the last two decades. These studies ship in a mountain lake in order to assess have mostly considered the case of towed the efficacy of the array processing arrays [12]. In the case of pass-by noise proposed in the ARMADA project. The pass- mapping, the idea developed in the project by configuration was separated between was to replace towed arrays by vehicle artificial sources and own model ship displacement to synthetize a larger array. sources. The former proved the Another specificity of the underwater performances of the methodology and the application is the small distance between latter permitted first analysis in accordance the surface ship and the array compared to with state-of-the-art results for true the ship size, leading to beamforming level hydroacoustic sources. The application of amplification on the map border. The issue the new weighting strategy on a has been solved with specific weighting, configuration of two sources shows a which smooths the distance working from dramatic reduction in the number of non- the distance to the array center [6]. physical sources. The localization and contribution results are thus more accurate,

46 improving the physical interpretation of the sound field radiated by vehicles during results. Moreover, an experiment with two standardized passby tests,” Journal of Sound low-frequency sinusoidal sources was and Vibration, vol. 233, no. 1, pp. 137–156, considered. The use of the synthetic 2000. aperture array method made it possible to [6] L. Lamotte, B. Nicolas, B. Oudompheng, M.Q. localize both sources with the synthetic Pham et D. Fattaccioli, « ARMADA: antenna, which is not possible with the real localization et contribution de sources au antenna. It is therefore possible to obtain bruit de passage d’un navire » CAF congress, La Mans 2016 more accurate results from blind deconvolution as the number of sources is [7] C. Audoly, C. Rousset, and T. Leissing, “Aquo small enough and they do not spread project–modelling of ships as noise source for use in an underwater noise footprint spatially. assessment tool”, in INTER-NOISE and Thanks to the ARMADA project, the NOISE24CON Congress and Conference feasibility of surface ship pass-by noise with Proceedings, volume 249, 862–871 (Institute accurate sound source identification was of Noise Control Engineering) (2014). established. The methodology works from a [8] Benoit Oudompheng, Cédric Gervaise, Lucille linear hydrophone array of a few sensors Lamotte, Wendyam Ouedraogo, Barbara deployed in the ship direction, which is a Nicolas, Jérôme I. Mars, « Modélisation temporelle des sources acoustiques d’un realistic set-up for industrial processing. bâtiment marin ou sous-marin en Advanced processing makes it possible to mouvement dans le champ lointain”, 24ème compensate the measurement difficulties Colloque sur le Traitement du Signal et des (small arrays, trajectory uncertainties, noisy Images (GRETSI 13), Brest, 2013. environment). Future perspectives will be [9] X.-p. GAO, B. Yi, and G.-p. MIAO, “Flow noise to apply the methodology to a real ship at measurement of surface ship with towed sea. The bottlenecks are now on model,” Journal of Hydrodynamics, Ser. B, experimentations rather than processing: vol. 20, no. 6, pp. 784–789, 2008. trajectory measurement, deploying an [10] C. D. Jong, J. Bosschers, and H. Hasenpflug, array, accurately positioning the array. “Model scale measurements of surface ship radiated flow noise,” in NAGDAGA, References International Conference on Acoustics, 2009. [1] ASA, “S12.64-2009 quantities and procedures [11] Benoit Oudompheng, Barbara Nicolas and for description and measurement of Lucille Lamotte, “Passive synthetic aperture underwater sound from ships - part 1: array to improve noise mapping of a moving General requirements”, (2009). ship”, IEEE/MTS Ocean, Gènes, Mai 2015. [2] ISO, “Iso/pas 17208-1:2012 - quantities and [12] S. Stergiopoulos and E. J. Sullivan, “Extended procedures for description and measurement towed array processing by an overlap of underwater sound from ships - part 1: correlator,” The Journal of the Acoustical General requirements for measurements in Society of America, vol. 86, no. 1, deep water”, (2012). pp. 158-171, 1989. [3] V. Fleury and J. Bult´e, “Extension of [13] Mai Quyen Pham, Benoit Oudompheng, deconvolution algorithms for the mapping of Barbara Nicolas, and Jérôme Mars, “SPARSE moving acoustic sources,” The Journal of the DECONVOLUTION FOR MOVING-SOURCE Acoustical Society of America, vol. 129, LOCALIZATION”, ICASSP 2016 p. 1417, 2011. [14] B. Oudompheng, B. Nicolas and L. Lamotte, [4] B. Barsikow and W. King, “On removing the “ACOUSTIC CORRECTION OF TRAJECTORY doppler frequency shift from array MISMATCHES TO IMPROVE MAPPING OF nd measurements of railway noise,” Journal of MOVING SOURCES”, Proceedings of the 23 Sound and Vibration, vol. 120, no. 1, pp. European Signal Processing Conference 190-196, 1988. (EUSIPCO), Septembre 2015 [5] H. Kook, G. Moebs, P. Davies, and J. Bolton, “An efficient procedure for visualizing the

47 Hydrophones antenna in Castillon lake Measurement and localization of ship noisy sources

48 REVIEW ON EXISTING DATA ON UNDERWATER SOUNDS PRODUCED BY THE OIL AND GAS INDUSTRY (FOR THE JOINT INDUSTRY PROGRAMME)

Nikhil Banda, Rachel Glanfield & Roy Wyatt Seiche Ltd, Bradworthy Ind Est, Devon, UK. EX22 7SX

During the exploration, development, scope of the measurements due to the vessel production and decommissioning phases of availability time, operational, recording and offshore oil and gas reserves, the industries weather constraints. Comparison between contribute to the noise levels in the oceans, measurements by different observers can be and rivers of the world. The difficult due to the vast range of ever purpose of the latest JIP review report [1] is changing conditions encountered in the to provide an updated catalogue and assess ocean and the range of metrics that can be the available data that characterise the used to describe the acoustic properties of a underwater sounds made by the oil and gas sound source. It is well known that, local industries in all phases of their activities, till conditions (geographic, geological, date. The latest JIP report builds upon the oceanographic and meteorological) all have works of a similar report [2] compiled by a very substantial impact on the way in Roy Wyatt in 2008. However; due to the which sound propagates from a source, scarcity of data in some areas - either due to through the water, and to a measurement the classified nature of the reports or receiver. As the receiver is often located at a otherwise - other noise sources such as considerable distance from the source, it is shipping, hovercraft and other production usually necessary to measure/quantify noises are also included in relevant sections many other parameters (related both to the for comparative purposes. transducers and the ocean) in order to attempt to determine the true nature of the Measurements of underwater noise source itself. generated by the Oil and Gas industry are scarce. Given the volume of traffic and The noise levels summarized in the JIP industrial activity around the shores of the ambient noise review report [1] are stated oceans, it is surprising that so little is known either as values measured by the of the likely impact the man-made noise corresponding researcher(s) or in an may have within the oceans and to the extrapolated form (to a distance of 1 m from marine life that resides within. the source) following a consistent set of Measurements of acoustic noise made over units. To do this extrapolation, a number of the last 40 years, at a site off the southern assumptions have been made, particularly Californian coast, reported a general relating to the local conditions under which increase in low frequency noise (< 150 Hz) the measurements were determined, the with time [3]. The increase in this noise nature of the source signal and propagation level has been widely attributed to increases characteristics. The readers of the report in shipping and other anthropogenic were however forewarned that the (human made) noise (often termed extrapolated values be used as guideline anthropogenic noise). In some areas, the only [1], as the variability of the noise background levels have been transmission of sound and the nature or the reportedly doubled every decade for the last sound source itself is difficult to quantify six decades, primarily due to the increased and an accurate translation between the shipping [3]. remotely measured values and the extrapolated (back projected) values is Few measurements have been made on sometimes difficult. underwater noise sources, and those that have been made are often limited in the

49 The JIP report [1] also contains a summary References anthropogenic noise values published in various research articles, commercial and [1] Banda N., Glanfield R. and Wyatt R. (2015). Joint Industry Programme Review on technical reports and other surveys for: Existing Data on Underwater Sounds seismic exploration sources; engineering Produced by the Oil and Gas Industry. Issue 2. sources such as: profilers, deterrent devices, Seiche Ltd, Braworthy. JIP. sonars, communication devices, explosives, [2] Roy, W. (2008). Joint Industry Programme on pingers/boomers; vessel noise generated Sound and Marine Life Review of Existing from various type of commercial shipping or Data on Underwater Sounds Produced by the other related sources; underwater Oil and Gas Industry, Seiche Ltd, Great construction, drilling and dredging noise; torrington. production and other related noise sources. [3] McDonald, M. A., Hilderbrand, J. A., and The data presented in the JIP report covers Wiggins, S. M. (2006). Increases in deep the literature published/reviewed till date. ocean ambient noise in the Northeast Pacific west of San Nicolas Island, California, Journal of Acoustical Society of America, 120, 8.

50 STANDARDIZATION IN UNDERWATER ACOUSTICS – NEEDS AND STATUS

Christian Audoly DCNS Research, France

Introduction internationally approved standards for underwater acoustics. A standard is a document that provides requirements, specifications, guidelines or Needs for standardization in characteristics that can be used consistently underwater acoustics to ensure that materials, products, processes and services are fit for their Electromagnetic waves propagate poorly purpose. underwater, contrarily to acoustic waves which can be observed at long distance from International Standards bring technological, the emitter, depending on source level and economic and societal benefits. They help to frequency. harmonize technical specifications of products and services making industry The development of the first sonar systems more efficient and breaking down barriers together with about one to international trade. Conformity to century ago has initiated an extensive use of International Standards helps reassure underwater sound by navies mainly in consumers that products are safe, efficient relation to underwater warfare. Underwater and good for the environment. acoustic detection and stealth, as well as mine warfare, are the main issues for Standardization should not be confused military naval applications, and for that with regulation. For example, in the domain purpose the different terms of the sonar of aerial acoustics, the requirement that equation must be determined properly. such maximum noise level or indicator is to Despite the fact that Navies use their own be fulfilled in a given environment (e.g. procedures which can vary depending on workspaces) for a given human activity is a the countries, there is an interest for a regulation, and the procedure and set-up for common terminology, and for accurate the measurement is a standard. A standard methods for the measurement of radiated may also impose a design requirement on a noise from vessels and of the acoustical product. Policy makers will use standards as characteristics of sonar systems. far as possible to enforce a regulation. There are also similar needs for civilian Contrarily to airborne acoustics where applications where underwater acoustic many documents have been made available detection has been used for a long time and for different purposes for a long time, no is still expanding. Apart from the industrial standard was available for underwater exploitation of the seas which will be acoustics until now. One of the main reasons addressed below, applications include: is that most of the topic was in relationship with military purposes, each Navy using its  Echo sounding, determination of sea floor properties, own procedures while keeping confidentiality. The increasing development  Detection of objects on the sea floor, such as wrecks or objects of historical interest, of anthropogenic activity at sea combined with the awareness of bio-acousticians  Fish detection, in order to locate and optimize caches, regarding environmental impact and  protection of marine life changes the Sea life monitoring and bioacoustics, context. There is currently a consensus  Acoustic ocean tomography and remote detection of seismic events. among stakeholders (scientists, industry, government representatives and policy Note also that since 1995 most of research makers) to have at one’s disposal some vessels are designed with a limit value of

51 underwater radiated noise, defined by an energy production, and the seas offer a ICES working group. great potential, using different types of systems: wind turbines mounted on piles More recently the increasing worldwide or on floating structures, underwater demand of energy and natural resources tidal turbines, ocean thermal converters. and the globalization of economy have led to The main matter of concern is the pile a steady increase of maritime traffic and driving operation during the installation industrial anthropogenic activity at sea. The phase of offshore wind turbines, which increasing concern of the scientific produces high intensity impulsive sound (note that at least two countries, community regarding the impact of Germany and Netherland, have already underwater sound on marine life incites enforced a regulation on that aspect with policy makers and stakeholders of the limit levels). On the other hand, the noise maritime domain to mitigate their impact emitted during the operational phases through appropriate measures. An should not be neglected, in particular important milestone was the adoption of the when several devices are installed close MSFD (Marine Strategy Framework one to the others. Directive) requiring European Member In that context the priority needs for States to monitor the environmental status standardization are the determination of of maritime areas and to take appropriate source levels emitted by ships and possibly measures to achieve a good environmental other sound sources, the sound emitted by status (MSFD, 2008). pile driving operations and the measurement of ambient noise in relation The main topics in relation with with anthropogenic activity. anthropogenic activity at sea are:  Maritime traffic: Noise and vibrations on Status of actions for standardization board ships has been a priority topic for at international level a long time at IMO (International Maritime Organization), because of crew A few years ago, a new subcommittee safety or passenger comfort issues. ISO/TC 43/SC 3 "Underwater acoustics" was Recently, the IMO issued non-mandatory created with the following scope: guidelines for the design of commercial “Standardization in the field of underwater vessels with the objective the protection acoustics (including natural, biological, and of marine life (IMO, 2014). Besides, the anthropogenic sound), including methods of European Union supported two measurement and assessment of the collaborative with the objective to generation, propagation and reception of mitigate underwater noise related to shipping in European maritime areas, underwater sound and its reflection and including also research on propeller scattering in the underwater environment cavitation noise, which is a major noise including the seabed, sea surface and source on commercial vessels. Synthesis biological organisms, and also including all documents of these projects are (AQUO & aspects of the effects of underwater sound SONIC, 2015), and (AQUO, 2015) with a on the underwater environment, summary in (Audoly, 2016) for the latter. and aquatic life”.  Oil and gas survey and exploitation: The search of offshore oil and gas fields in the Four working group are currently active: sediment layers beneath sea bottom is  Measurement of underwater sound from done through seismic surveys requiring ships: A first standard, the ISO 17208-1, the emission of low frequency high was published in the beginning of year intensity impulsive sounds produced by 2016, dealing with “Measurement of “underwater air guns”. Another aspect is underwater sound from ships — Part 1: related to the preparatory phases for Requirements for precision exploitation and the operational phases. measurements in deep water used for There, some noisy underwater activity comparison purposes. A second part of can occur (drilling, pumping, conveying this standard is under study with the fluids and/or sediments in pipes) purpose to determine the ship source  Marine renewable energy: There is level, instead of the radiated noise level currently a move to develop renewable

52 affected by the reflection of waves on the environmental impact assessment studies, sea surface, by applying a correction the standards organizations, in particular term. the ISO/TC 43/SC 3 are working actively to  Underwater Acoustics – Terminology: fill the gaps. A first standard for the the objective is here the adoption a measurement of radiated noise from ships common language, as presented in was published recently, and two others on (Ainslie, 2016). The corresponding terminology and sound arising from marine standard, the ISO 18405, is nearly completed. pile driving are expected soon. A work plan has been established for future actions.  Measurement of radiated noise from marine pile driving: The ISO 18406 is completed and could be published References shortly. Ainslie, MA et al. 2016, Standardization of  Standard-target method of calibrating Underwater Acoustical Terminology: Why active sonars: The work in progress, bother?, Proceedings of the 4th International project ISO 20073, is dealing with a Conference on The Effects of Noise on method based on the use of reference Aquatic Life, Dublin, Ireland, 10-16 June calibrated targets for calibration of active 2016. sonars for imaging and measuring scattering, which is of interest for both AQUO Project, Synthesis of recommendations, civilian and military applications. Underwater Noise Footprint of Shipping: The Practical Guide. AQUO report D5.8 (2015), Other topics considered for the future in the http://www.aquo.eu. work plan are: AQUO & SONIC Projects, Guidelines for  Underwater acoustics – Measurement of Regulation on UW noise from commercial ambient sound shipping, prepared by AQUO and SONIC  Underwater acoustics – Measurement of Projects, 30 November 2015, sound pressure http://www.dnvgl.com/sonic  Underwater acoustics – Measurement of Audoly, C, Rousset, C, Baudin, E & Folegot, T sound from offshore petroleum 2016, “AQUO project - Research on solutions operations for the mitigation of shipping noise and its  Underwater acoustics – Calibration of impact on marine fauna – Synthesis of autonomous acoustic receiver/recorder guidelines”, Proceedings of the 23rd systems International Congress on Sound and Apart from the actions at the level of the Vibration, Athens, Greece, 10-14 July 2016. ISO, the IEC is also contributing to the IMO, Guidelines for the reduction of underwater standardization issues in underwater noise from commercial shipping to address acoustics with a working group on “Acoustic adverse impacts on marine life, MEPC.1/Circ.833, International Maritime Characterization of Marine Energy Organization, 7 April 2014. Converters”, in particular tidal turbines. ISO, Underwater acoustics — Quantities and Summary and way ahead procedures for description and measurement of underwater sound from ships — Part 1: Despite the existence of specific procedures Requirements for precision measurements in within Navies and some national standards deep water used for comparison purposes, ISO 17208-1:2016, International or regulating documents, no international Standardization Organization, Geneva. standard was available until now in underwater acoustics. As it is of general MSFD, Directive 2008/56/EC establishing a interest for stakeholders and scientists to framework for community action in the field of the marine environment policy (Marine adopt common language and procedures, in Framework Strategy Directive). European particular in order to compare Commission, 17 June 2008. measurements one to the others and to be able to carry out good quality

53

HOW EFFICIENT ARE POTENTIAL REGULATIONS ON UNDERWATER NOISE? A FRAMEWORK PROPOSED BY THE AQUO PROJECT

Éric Baudin(1), Céline Rousset(2), Christian Audoly(2), Thomas Folegot(3) & Michel André(4) (1) Bureau Veritas, 67-71 Boulevard du Château, 92571 Neuilly sur Seine, France (2) DCNS Research, Technopole de la Mer, 83190 Ollioules, France (3) Quiet-Oceans, 65 place Nicolas Copernic, 29280 Plouzane, France (4) Laboratory of Applied Bioacoustics, Technical University of Catalonia, BarcelonaTech (UPC), Spain

The 7th Framework Program, within the be linked mainly with oil and gas scope of « Sustainable Surface Transport » exploration or pile driving) and low and « Oceans of Tomorrow » has funded the frequency continuous noise from shipping. three-year research project “AQUO”, The research efforts of AQUO have focused covering the impact of underwater noise on listing and assessing practical solutions radiated (URN) from shipping and its with regards to the latter. It has to be adverse impact on the fauna. mentioned here that the EU funded as well another project “SONIC” on the same topic AQUO’s goal based approach aimed at committing both consortia to deliver building a methodology and the consistent and commonly structured corresponding tools to help the policy outcomes and guidelines [6]. It has makers establishing the most appropriate highlighted meanwhile the importance of mitigation plans for the concerned waters. the topic. The main issues of the underwater noise Moreover, to emphasize the position of the topic (governance, measurements on site topic, it is of prime importance to mention and in basin, source and propagation the milestones of the IMO guidelines models, species, technical solutions and adopted 2014 [2].and the issuing of ISO mitigation scenarios) have been addressed 17208-1 in March 2016 [3]. throughout the different work packages. They constitute the skeleton of the AQUO Methodology overview final guidelines and support the overall methodology that is described in this paper. The aim of AQUO’s approach is to enable a practical assessment of the various Introduction and context solutions and mitigation measures. Let’s list down the key stones to understand how it The scientific community’s concern on the has been built. underwater noise on anthropogenic maritime activity and its adverse impact on At both ends of the noise radiated from marine life increased together with ship shipping, there are: traffic status and trends.  each ship considered as a single noise Until 2008, none of the Oceans and source, biodiversity related international  ship traffic, to be considered as an conventions and National regulations have accumulation of noise sources, explicitly addressed underwater noise  the resulting noise is thus pending to be issues. Since then, throughout the Marine managed as accurately as possible, Strategy Framework Directive (MSFD) [1],  predictive values of noise sources from the European Union clearly identified numerical (URN patterns, [11]) and underwater noise as one of the descriptor of scaled (basin mock-up) models, the Good Environmental Status of its waters.  on-site measurements, including the Two indicators have been set-up to address mandatory insight on the related the two main types of noise linked to uncertainties, anthropogenic activities: impulsive noise (to

55  ship traffic data from available Automatic  noise mitigation direct scenarios at a Identification System, ship traffic level, linking ship operation  sound propagation phenomena from strategies and underwater noise, multiple single sources to a whole basin  technical solutions and their expected scale, noise reduction at a single ship level,  appropriate and representative noise generally through improved design or indicators within time and space using alternatively by retrofit, further percentiles. extrapolated to ship traffic. Furthermore, the core of the topic is not These simulations express the benefits not only the noise level on its own but its only for noise levels at a basin scale but for a potential impact on the receivers (i.e. given species providing a given sensitivity marine fauna). It is thus necessary to criteria. identify: Figure 1 illustrates these different key  the species of interest, stones and how the AQUO methodology  their corresponding noise sensitivity leads to assess the noise footprint from criteria. shipping: Four main processing chains This embedded three-axis approach related to the selection to the relevant including single ship noise sources, ship species to be considered, the physical traffic and species provided by the LIDO characteristics and the shipping software package (listentothedeep.com)1 characteristic of the area, and the individual constitutes the skeleton of the methodology properties of the vessels converge toward and the key inputs of the corresponding the Quonops© tool which will assemble all Quonops® patented tool [12] that enables a this information to deliver the related quantitative assessment through the statistical noise maps. The application of production of noise maps. Considering real noise reduction scenario will modify the time actual data, a picture of the current statistical noise maps and allows for a situation can be obtained, but one of the quantitative assessment of the efficiency of highest added-value of the methodology is the mitigation measures envisioned. also to assess the consequences of:

Figure 1: Overall AQUO’s methodology

1 http://www.listentothedeep.com/

56

Applicability AQUO has shown that imposing a regulatory limit of to the noisiest ships seems to be the The results of this methodology depend on most effective solution, which is consistent the specificities of the area where it is with the recent Bureau Veritas (BV) URN applied, but the method itself is wide- class notation NR614 [5]. Fulfilling BV ranging and can be applied in any maritime requirement could be achieved by an area. To demonstrate this feature, the improvement in design of future vessels, method has been applied during the AQUO and for existing vessels by proper project timeline in three different locations: maintenance and by adapting operational offshore Brittany and South-East coast of settings. However, it is not realistic to France and offshore Barcelona, Spain. This impose noise limits for all vessels in all practical implementation went through all maritime areas. Therefore it is the role of the mandatory steps of baseline Member States to define the priority areas measurements and model calibration and related marine species to be protected. processes [7], [10]. The final message is not to highlight one or Figure 2 summarizes the scenarios which another solution but to make available a were developed [8], [9] and tested within solution package that should be used by the framework of AQUO. It demonstrates policy makers, protected area managers, the maturity of Quonops®, able to quantify port authorities or ship owners to decide the benefits in terms of noise and in terms through appropriate criteria, what solutions of impact on the fauna. should be preferred with regards to their benefits. It has also to be noted that the commitment of AQUO’s consortium to achieve practical The best way ahead would be to deploy the guidelines [4] has been ensured by working methodology and tools in some pilot areas also on the solutions considering: involving all the stakeholders (owners and operators, biologists, policy makers and  The influence on fuel efficiency, evaluators).  The implementation difficulties with regards to direct design, refit and maintenance costs.

Figure 2: Overview of the scenario tested using AQUO’s methodology and Quonops® and corresponding results

57 Acknowledgements 6 Guidelines for Regulation on UW noise from commercial shipping, prepared by AQUO and This work was developed in the frame of the SONIC Projects, 30 November 2015 collaborative project AQUO (Achieve 7 Folegot, T., van der Schaar, M., Clorennec, D., QUieter Oceans by shipping noise footprint Brunet, P., Six, L., Chavanne, R., and André, M., reduction), funded by the European Monitoring Long Term Ocean Noise in Commission within the Call FP7 European Waters, Proceedings of the IEEE- SST.2012.1.1-1: Assessment and mitigation MTS Oceans’15 Conference, Genoa, Italy, 19-21 May, (2015). of noise impacts of the maritime transport on the marine environment, Grant 8 Colin, M., Ainslie, M., de Jong, C., Binnerts, B., agreement no 314227, coordinated topic Beeks, T., Ostberg, M., Karasalo, I., Folegot, T., Clorennec, D., Sertlek, O., Jansen, E., Definition “The Ocean of Tomorrow”. The content of and results of test cases for shipping sound this paper does not reflect the official maps. Proceedings of the IEEE-MTS opinion of the European Union. Oceans’15 Conference, Genoa, Italy, 19-21 Responsibility for the information and May, (2015). views expressed in the paper lie entirely 9 Christian Audoly, Celine Rousset, Raúl with the authors. Salinas, Enrico Rizzuto, Jan Hallander, Eric Baudin, Mitigation measures for controlling References the ship underwater radiated noise, in the scope of AQUO Project. Proceedings of the 1 European Commission, Maritime Strategy IEEE-MTS Oceans’15 Conference, Genoa, Framework Directive 2008/56/EC, Italy, 19-21 May, (2015). pp. L164/19-40, 2008. 10 Gaggero, T., Karasalo, I., Östberg, M., Folegot, 2 IMO, Guidelines for the reduction of T., Six, L., van der Schaar, M., André, M., underwater noise from commercial shipping Rizzuto, E., Validation of a simulation tool for to address adverse impacts on marine life, ship traffic noise, Proceedings of the IEEE- MEPC.1/Circ.833, 7 April 2014 MTS Oceans’15 Conference, Genoa, Italy, 3 ISO 17208-1:2016 “Underwater acoustics -- 19-21 May, (2015). Quantities and procedures for description 11 Audoly, C., Rousset, C., Leissing, T., AQUO and measurement of underwater sound from Project – Modelling of ships as noise sources ships -- Part 1: Requirements for precision for use in an underwater noise footprint measurements in deep water used for assessment tool, Proceedings of Internoise th comparison purposes”, Published on the 15 Conference, Melbourne, Australia, 16-19 of March 2016. November, (2014). 4 Synthesis of recommendations. “Underwater 12 Folegot, T., Method for monitoring, predicting Noise Footprint of Shipping: The Practical and reducing the level of acoustic energy of a Guide”. AQUO Project, report D5.8 (2015). plurality of sources in an aquatic 5 “Underwater Radiated Noise (URN), Rule environment and method for monitoring, Note NR 614 DT R00 E”, Bureau Veritas, predicting, and reducing the risk of noise 2014. annoyance for marine species. European Union Patent EP2488839. 10 October 2009.

58 HOW DOES THE MARINE STRATEGY FRAMEWORK DIRECTIVE PROTECT EUROPEAN SEAS & OCEANS FROM THE IMPACTS OF UNDERWATER NOISE?

Lydia Martin-Roumégas Second National Expert, Policy Officer at the Directorate-General of Environment of the European Commission

This presentation informs the assembly of Environmental impact assessments the international conference on underwater & Strategic Environmental Assessments noise: Racket in the oceans on the frame of the Marine Strategy Framework Directive In direct relation to all permitting activities (MSFD) and underwater noise issues and to such as seismic survey from oil and gas develop further advices on the exploration, dredging activities, the package implementation of the second cycle of the of environmental impact assessment from Marine Strategy Framework Directive. strategies to the projects will apply. It includes: Firstly, the main Union environmental  the strategic environmental assessment, regulation linked to underwater noise falling under the scope of Directive issues, including the Environmental impacts 2001/42/EC1 on the assessment of the assessment Directive, the Strategic effects of certain plans and programmes environmental assessment Directives and on the environment and on public finally the Marine strategy framework consultation in early decision-making directive, associated to its good process; environmental status commission decision  the environmental impact assessment of will be described. projects falling under the scope of Directive 2011/92/EU2 (codified) on the Secondly, the decision on the good assessment of the effects of certain environmental status of Union marine public and private projects on the waters will be presented, including environment. information on its ongoing revision process. Principles laid down in the strategic Thirdly, an overview of the progress and the environmental assessments are: existing references developed under MSFD, in particular through the technical group on  to provide for a high level of protection underwater noises (TG noise) will be given. of the environment;  to contribute to the integration of Fourthly, the presentation will highlight the environmental considerations into the future actions of the draft work programme preparation of plans and programmes for 2016-2019 on the common with a view to promoting sustainable implementation strategy of MSFD. development. For the environmental impact assessment EU laws protecting the marine principles are: environment from adverse underwater noise effect 1 Directive 2011/92/EU of the European Parliament This part of the presentation provides an and of the Council of 13.12.2011 on the assessment overview of the EU legislation contributing of the effects of certain public and private projects to the prevention of anthropogenic noise in on the environment Text with EEA relevance OJ L 26, European Union seas. 28.1.2012, p. 1‐21. 2 Directive 2008/56/EC of the European Parliament and of the Council of 17.6.2008 establishing a framework for community action in the field of marine environmental policy (Marine Strategy Framework Directive) (Text with EEA relevance) OJ L 164, 25.6.2008, p. 19‐40.

59  to protect the environment and quality of to zero for man-made synthetic life; substances.  to ensure approximation of national laws Also, depending on the nature of the with regard to the assessment of the projects, their emissions and products, environmental effects of public and other directives may apply such as the private projects. landfill directive3 and the industrial Certain public plans and programmes that emission directive4. are likely to have significant effects on the environment should be subject to a strategic The Marine Strategy Framework Directive environmental assessment, as required The Marine Directive, establishing a under the Directive bearing the same name. framework for community action in the field Public and private projects that are likely to of marine environmental policy (MSFD, have significant effects on the environment Directive 2008/56/EC), aims to achieve the are subject to an environmental impact “good environmental status” of the EU’s assessment, as required by the marine waters by 2020. Seas in good Environmental impact assessment directive. environmental status are clean, healthy and Other directives may apply, given that they productive and are characterised by 11 have an indirect link with permitting and topics called descriptors. The directive also recreational human activities. Together, all emphasises the need to maintain a these laws contribute to the overall goal of sustainable use of marine resources and it preserving our common and shared implies managing the pressure exercised by environment on ecosystem entities. These human activities on the marine include the Water Framework Directive, environment, including -based Habitats Directive, Birds Directive, Marine activities. The ecosystem-based approach is Strategy Framework Directive, Invasive an underlying principle of the directive. alien species Directive, Air quality Directive Each Member State is required to develop and others. and implement a marine strategy in its marine waters, in cooperation with other The Water Framework Directive (WFD): Member States sharing the same marine This Directive, establishing a Union in the region. This strategy is reviewed every 6 field of water policy applies to each river years. basin district lying within the territory of Those strategies include 5 steps: the Member States. The amended directive 2000/60/EC of the European Parliament 1. an initial assessment of reported in 2012 & and of the Council establishing a framework their marine waters, to be revised in 2018 2. the determination of the reported in 2012 & for the Community action in the field of good environmental status to be revised in 2018 water policy Its purpose, as stated in article of their marine waters, 1, is to establish a framework for the 3. the setting of reported in 2012 & protection of inland surface waters, environmental targets to be revised in 2018 transitional waters, coastal waters and 4. the establishment and reported in 2014 & groundwater… and thereby contributes to : implementation of to be revised in 2020 coordinated monitoring  the protection of territorial and parts of programmes, and marine waters; and 5. the identification of reported in 2015 & measures or actions that to be revised in 2021  achieving the objectives of relevant need to be taken in order international agreements, including to achieve or maintain those which aim to prevent and eliminate good environmental status pollution of the marine environment, by Union action under its Article 16(3) to cease or phase out discharges, emissions and losses of priority hazardous substances, with the ultimate aim of 3 Council Directive 99/31/EC of 26 April 1999 on the achieving in the marine landfill of waste. environment near background values for 4 Directive 2010/75/EU of the European Parliament naturally occurring substances and close and the Council on industrial emissions.

60 upon which GES should be based. As such, GES is achieved when,  Descriptor 1. Biodiversity is maintained  Descriptor 2. Non-indigenous species do not adversely alter the ecosystem  Descriptor 3. The population of commercial fish species is healthy  Descriptor 4. Elements of food webs ensure long-term abundance and reproduction  Descriptor 5. Eutrophication is reduced  Descriptor 6. The sea floor integrity ensures functioning of the ecosystem  Descriptor 7. Permanent alteration of In 2012, for the first time Member States hydrographical conditions does not reported on the state of their marine waters, adversely affect the ecosystem on what they consider as being their “good  Descriptor 8. Concentrations of environmental status” to reach in 2020 and contaminants give no effects on their objectives and targets. The  Descriptor 9. Contaminants in seafood European Commission assessed these first are below safe levels elements of the strategy against the  Descriptor 10. Marine litter does not Directive’s requirements in 2014 and cause harm highlighted that Member States had to put  Descriptor 11. Introduction of energy more effort to be able to reach the 2020 (including underwater noise) does not adversely affect the ecosystem. goal. For example there was need to focus 6 more on joint action and planning and more A 2010 Commission legislation further ambitious regional cooperation so as to detailed a set of parameters to help Member improve coherence in the implementation of States in characterising and defining “good eth Directive across the EU’s waters. environmental status” of their marine waters. For underwater noise, it looks at A second Commission report5 assessing anthropogenic sounds that may be of short Member States’ monitoring programmes, duration (e.g. impulsive such as from adopted in January 2017 highlights that seismic surveys and piling for wind farms monitoring programmes are either and platforms, as well as explosions or long incomplete, or will be put in place too late. lasting (e.g. continuous such as dredging, shipping and energy installations). Member The ‘Good environmental status’ States would have to measure the Decision: more focus on state & Distribution in time and place of loud, low pressure notions and mid frequency impulsive sounds as well as look at trends in emissions of continuous The MSFD defines “good environmental low frequency sound. status” as “the environmental status of marine waters where these provide This piece of legislation is currently under ecologically diverse and dynamic oceans review since 2014, and a revised proposal and seas which are clean, healthy and was voted favourably by the MSFD productive”. GES implies that marine regulatory committee last November. The resources are used sustainably, ensuring revised version develops the notions of their continuity for future generations. The state, pressure and impact on marine MSFD sets out eleven qualitative descriptors waters, while elaborating on the criteria and

5 Report from the Commission to the European 6 Commission Decision of 1 September 2010 on Parliament and the Council assessing Member criteria and methodological standards on good States' monitoring programmes under the Marine environmental status of marine waters, Strategy Framework Directive, COM/2017/03 final 2010/477/EU.

61 methodological standards to be applied by promote joint monitoring programmes for Member States in their determination of ambient noise in Europe. TG noise advice good environmental status, and the could thereby enable Member States to assessments and monitoring of their seas. make a proper assessment of their progress towards achieving good environmental Achievements of the MSFD technical status for this particular descriptor. group on underwater noise A list of reference documents on The MSFD’s “Common implementation underwater noise and MSFD at European Strategy”, which brings EU Member States’ level are suggested at the end of the article. experts and stakeholders together to discuss MSFD issues, has a technical group Future objectives, tasks for the MSFD on underwater noise referred to as TG technical group on underwater noise Noise. It is tasked to share experiences and develop guidelines for assessment and During 2016-2019, TG Noise will pursue a monitoring. In 2012 it drafted a report number of tasks. It will continue to assist clarifying7 the purpose, use and limitation of Member States and Regional Sea the indicators and described methodology Conventions on the implementation of that would be “unambiguous, effective and operational monitoring on a number of practicable”. issues, notably:  Establishing the monitoring of ambient The TG Noise had subsequently identified noise in a (sub)region; potential priority work items for support to  Establishing and interpreting of the noise the operational implementation of registers; Descriptor 11. In 2013, the main focus of TG  Applying agreed criteria to provide Noise was on developing operational advice on additional indicators for noise guidance for monitoring and noise and other forms of energy; registration for member states. This  Provide input to and follow-up on the document provided EU Member States with review of the GES decision with regard to the information needed to set up monitoring descriptor 11; in their marine waters, as required by the  Assessment of good environmental MSFD. In 2014, TG Noise provided further status ; advice on the actual progress of monitoring  Review outcomes of relevant projects. and including advises for the review of the Other tasks include providing advice on Commission Decision. Since 2015 TG Noise future assessments; developing work on has been working on the upcoming updates impacts of noise and noise pressure of the Art.8 MSFD assessment, while still indicators; and ensuring regional coherence watching progress on monitoring, in notably in developing coordinated particular for the Mediterranean and Black monitoring and Regional Action Plans. The Sea regions. TG noise has also followed and work in the TG Noise is related to activities discussed the development of a register for undertaken in Regional Seas Conventions impulsive noise, supported by the Regional with regard to setting up a register of loud sea conventions in the Baltic and North impulsive noise and the development of a Atlantic regions, OSPAR and HELCOM. This joint monitoring programme for ambient register is now available and collected by noise, though not exclusively. TG Noise International Council for the Exploration of provides the link between existing regional the Seas (ICES). TG Noise also serves as a initiatives (OSPAR ICG Noise), BIAS platform for discussions to initiate and (HELCOM) and other Member States in regions where initiative are now under 7 Van der Graaf AJ, Ainslie MA, André M, Brensing K, development, e.g. ACCOBAMS (Barcelona Dalen J, Dekeling RPA, Robinson S, Tasker ML, Convention). Thomsen F, Werner S (2012). European Marine Strategy Framework Directive - Good Environmental Status (MSFD GES): Report of the Technical Subgroup on Underwater noise and other forms of energy.

62 Mains issues and conclusions Main reference documents on underwater noise and MSFD at Member States have to implement their European level monitoring programme on underwater noise issues, as well as their programme of  2012, Van des Graaf AJ and al., European measures. They should get prepared for the Marine Strategy Framework Directive - updates of the assessment and target setting Good environmental status (MSFD GES): set for 2018. So it remains essential to Report of the technical subgroup on gather and analyse monitoring data sets. In underwater noise and other forms of addition, for impulsive noise, Member States energy, http://ec.europa.eu/environment- could use the ICES impulsive noise source /marine/pdf/MSFD_reportTSG_Noise.pdf register, developed under OSPAR and  2014, JRC Scientific and policy reports, Technical guidance on monitoring for HELCOM conventions. Other Regional Sea Marine Strategy Workshop elements, Conventions could also consider this http://publications.jrc.ec.europa.eu/repo impulsive noise register as a good example sitory/bitstream/JRC88073/lb-na- to develop. Also, for ambient noise, Member 26499-en-n.pdf.pdf States are encouraged to set up  2014, JRC Scientific and policy reports, joined/coordinated monitoring Monitoring guidance for underwater programmes developed at a regional levels, noise in European Seas. Part I Part II, as is for example the case for the one https://ec.europa.eu/jrc/en/publication/eur-sc developed by HELCOM. ientific-and- technical-research-reports/monitoring-guidanc Furthermore the use of biodiversity e-underwater-noise-european-seas- part-ii-monitoring-guidance descriptors to strengthen the analysis on the impacts of underwater noise remains  2015 CEFAS, Impacts of noise & use of propagation models to predict the crucial. Data, knowledge such as abundance, recipient side of noise. reproduction and behaviour of relevant key  Outcomes of MSFD TG noise 2016 species (e.g. marine mammals and fish) Workshop on impacts (still to be would be necessary to progress towards the published) analysis of underwater noise impacts on this  IMO MEPC.1/Circ.833: Guidelines for the relevant key-species. Reduction of Underwater Noise from Commercial Shipping to Address Adverse In conclusion, Member States should Impacts on Marine Life prepare the second cycle of MSFD, in  Accobams, 2013, methodological guide: revising by 2018 their targets, assessment “Guidance on underwater noise and GES of their marine waters, in regard to mitigation measures”. MSFD and to the future revised good  Member States guidance documents, environmental status decision. They should such as UK guide - 2014 -Good Practice move towards the development of good Guide No.133 Underwater noise environmental status by determining measurement, pressure thresholds. Through the https://www.gov.uk/government/news abovementioned MSFD Common /cefas-leads-development-of- Implementation Strategy and through underwater-noise-monitoring-network. funding opportunities such as LIFE+, EU funded projects related to underwater European Maritime and Fisheries Funds, noise issues such as AQUO SONIC, BIAS, Horizon 2020 and European Regional MARVEN and others are also representing Development Fund, the European good progress in the field. Commission is providing support to this effect, whereby. Underwater noise issues Relevant MSFD documents may also be and impacts are being considered. The found on CIRCABC (Environment/marine MSFD ensures that the EU's seas are used strategy), https://circabc.europa.eu/faces/jsp- sustainably. In this sense further progress /extension/wai/navigation/container.jsp and on underwater noise will provide more the MSFD Competence Centre clarity to how economic activity can develop http://mcc.jrc.ec.europa.eu. while respecting the marine environment.

63

FROM PAPER TO PRACTICE: APPROPRIATELY ASSESSING ANTHROPOGENIC NOISE IN OUR OCEANS

Nicolas Entrup(1), Geoff Prideaux(2) & Margi Prideaux(3) (1) Consultant to OceanCare/NRDC / (2) Wild Migration (3) Indo-Pacific Governance Research Centre

The ocean environment is filled with natural assessments should be mandatory for noise- sound from animals and physical processes. generating activities known to be in habitats Species living in this environment are for threatened species or in regions that adapted to these sounds. Over the past provide key ecosystem services and century anthropogenic marine activities stipulates important principles about have increased levels of noise, and in turn consummation and transparency.(CBD are causing physical, physiological and 2006) CBD Decision XII/23 also encourages behavioural impacts on marine fauna, governments to take appropriate measures, including cetaceans, pinnipeds, polar bears, including acoustic mapping with habitat sirenians, marine and sea otters, marine mapping of sound-sensitive species, turtles, fin-fish, elasmobranchs and marine mitigating and managing anthropogenic invertebrates including both molluscs and noise through the use of spatio-temporal crustaceans. (Southall et al 2007, management of activities and conducting Hildebrand 2009, André et al 2010, impact assessments for activities that may Prideaux et al, in press). have significant impacts (CBD 2014). Levels of threat are now well defined. The Convention on Migratory Species (CMS) Mitigation and monitoring guidelines exist Resolutions 9.19 and 10.24 each propose in many parts of the world. (Weir and the control of anthropogenic marine noise Dolman 2007) In many jurisdictions these in habitats of vulnerable species, and in guidelines rely on Environmental Impact areas where marine mammals or other Assessment (EIA) consideration by endangered species may be concentrated. decisions makers, yet few jurisdictions EIAs are encouraged prior to approving stipulate what such assessments should noise-generating activities (CMS 2008; contain. 2011). We articulate the existing commitments for The Agreement on the Conservation of European States, both EU and Non-EU Cetaceans in the Black Sea Mediterranean Member States, to conduct EIAs in the Sea and Contiguous Atlantic Area Mediterranean region; outline why clear (ACCOBAMS) Resolutions 4.17 urges guidelines about the content of EIAs are governments to ‘[r]ecogniz[e] that needed; and propose general principles that anthropogenic ocean noise is a form of should be included in these guidelines. pollution’ and conduct ‘thorough environmental impact assessments being EIAs for Marine Noise in Europe undertaken before granting approval to proposed noise-producing activities’. The A series of important intergovernmental ACCOBAMS Noise Guidelines provide decisions have already determined the further comprehensive detail-specific direction for regulating anthropogenic considerations relating to military sonar, marine noise through EIAs in Europe and seismic surveys and offshore drilling, the Mediterranean Sea. shipping and offshore renewable energy The Convention on Biological Diversity developments. ACCOBAMS Resolutions 5.13 (CBD) ‘CBD Voluntary Guidelines on and 5.15 reinforce these commitments Biodiversity-inclusive Impact Assessment’ (ACCOBAMS 2010; 2013; 2013b). urges that environmental impact

65 A number of pieces of European Union conducted or are completed in a cursory legislation on EIAs and nature protection manner. They often include misleading or are of direct relevance. Directive erroneous information, use distance as a 2014/52/EU of the European Parliament simplistic proxy for impact and generalize and the Council, specifically signals that about noise transmission without fully EIAs should be conducted for specific noise- investigating propagation (Wright et al generating activities and that ‘[e]xperts 2013; Prideaux and Prideaux 2015). involved in the preparation of environmental impact assessment reports The propagation of sound in water is should be qualified and competent. complex and requires many variables to be Sufficient expertise, in the relevant field of carefully considered before the impact of a the project concerned, is required for the noise-generating activity can be known. purpose of its examination by the Sound is a physical wave, and has effects on competent authorities in order to ensure organisms beyond hearing. Sound waves that the information provided by the move through a medium by transferring developer is complete and of a high level of kinetic energy from one to the quality.’ The Bern Convention, the EU next. Animals that are exposed to elevated Habitats Directive and EU Birds Directive anthropogenic noise will experience passive also articulate that significant disturbance resonance (particle motion) that may result should assessed and avoided in Natura 2000 in direct injuries () that can sites designated for the protection of range from bruising through to death. This features such as marine animal species damage can also include permanent or listed in Annex II of the Habitats directive. temporary auditory threshold shifts, This Habitats Directive also includes the compromising the animal’s communication obligation to assess the cumulative impacts and ability to detect threats. Finally, noise of different activities on the conservation can mask important natural sounds, such as objectives of the site and prohibits the call of a mate, the sound made by prey deliberate disturbance of strictly protected or a predator (Urick 1983; Lurton 2010; species that include all species of cetaceans Prideaux and Prideaux 2015, Aguilar de and a number of marine vertebrates and Soto and Kight 2016). invertebrates listed in Annex IV(a) (EU To present a defensible EIA for any noise- 1992; 2010; EC 2007; Bern Convention generating activity proposal, proponents 1979). should be required to expertly model the The United Nations Convention on the Law noise propagation of their proposed activity. of the Sea (UNCLOS) Article 206 contains The extent and way that sound propagates provision to assess and communicate the is affected by many factors, including the assessment of impacts on the marine frequency of the sound, water depth and environment, including forms of marine density differences within the water column pollution. (UNCLOS 1982) The International that vary with temperature, salinity and Maritime Organization (IMO) is developing pressure. Consequently, a sound arriving at guidance for the reduction of noise from an animal is subject to propagation commercial shipping and its adverse conditions that are complex. (Calambokidis impacts on marine life. (IMO 2013) And, the et al 2002; Hildebrand 2009; Lurton 2010; Espoo (EIA) Convention articulates the McCauley et al 2000) Modelling should be principles of public comment and specific to the region and under the transparency around such assessments conditions they plan to operate (Clay and (Espoo 2014). Medwin 1997; Etter 2013; Lurton 2010; Wagstaff 1981). Guidelines for Marine Noise Marine Noise EIA Content There are few regions of the world that have so comprehensive articulated the need for The basic intent of an EIA is to anticipate the EIAs relating to marine noise. Despite this, significant environmental impacts of a more often than not, EIAs are either not development proposal before any

66 commitment to a particular course of action the activity. Other parameters that should has been made. Therefore the detail be considered are water depth, seabed required within EIAs should be clearly topography, temperature and salinity, and defined. (Cashmore et al 2004; Devlin and whether spatial variation in the Yap 2008; Jay et al 2007). At a minimum, environment is significant (Urick 1983; EIAs for marine noise-generating activities Etter 2012; Farcas et al 2016). should: Particle motion is commonly not considered  provide adequate baseline biological and in EIA modelling. This is an important area environmental information to address, as fish and invertebrates detect  characterise operations and their sound through particle motion to identify acoustic components predator and prey, rather than through a  assess the impact on species and tympanic mechanism as with marine consider cumulative effect from mammals. Intense and/or prolonged anthropogenic activities exposure, particularly to low frequencies,  describe how impacts are to be mitigated can cause barotrauma in these animal and effectiveness monitored groups (Hawkins 1986; Popper and Fay  objectively compare the posed risk 2011; Morley et al 2014; Farcas et al 2016). against alternatives that may cause less impact Sound exposure level cumulative To provide this crucial information, expert (SELcum) noise modelling incorporating the The next important parameter that must be cumulative impact of sound exposure over a considered is the cumulative impact of period of time, should be required. sound exposure over a period of time. This Proponent-funded, independent, peer- is usually 24 hours, unless specified. EIAs review of EIA proposals, before submission should transparently report the predicted to regulators, is also important. Finally, sound exposure level cumulative (SELcum) transparency is necessary for well-informed for all marine species in the area. To consultation and natural justice. illustrate this importance, it is useful to Expert noise modelling consider the significant susceptibility difference of species to single or short The objective of noise modelling for EIAs is duration noise (represented as dB peak) to predict how much noise a particular and SELcum over a period of time. The activity will generate and how it will following table, drawn from the latest NOAA disperse. EIAs should present expert ‘Technical Guidance for Assessing the modelling of the full frequency bandwidth of Effects of Anthropogenic Sound on Marine a proposed anthropogenic noise source, the Mammal Hearing’ (NOAA 2016) intensity/pressure/energy output within demonstrates this difference and the the full frequency range of the source(s), not significantly lower threshold for impact of only the main output that is of interest to prolonged exposure.

Temporary threshold shift Permanent threshold shift Impulsive Non-impulsive Impulsive Non-impulsive SELcum 24h 140 dB 153 dB 155 dB 173 dB Bottlenose dolphin dB peak 196 dB n/a 202 dB 202 dB SELcum 24h 170 dB 178 dB 185 dB 198 dB Sperm whale dB peak 224 dB n/a 230 dB 230 dB Mediterranean SELcum 24h 170 dB 181 dB 185 dB 201 dB monk seal dB peak 212 dB n/a 218 dB 218 dB Adapted from NOAA 2016

67 Independent peer-review transparency and even evade environmental regulations. Proponent-funded independent peer-review of EIA proposals, before submission to In many countries it is common political regulators for assessment, is crucial tool and practise to allow industry proponents to a logical requirement for alignment of EIAs hide behind a veil of commercial sensitivity. with scientific understanding and standards, While not exposing information that is and ensuring that scientific understanding genuinely commercially or personally takes precedence over short-term benefits sensitive, the extent of transparency should and political considerations. (Morrison- always complement the goals of natural Saunders and Bailey 2003, DiMento and justice and consultation. The technical Ingram 2005, Sheaves et al 2015) details of any proposal for activities that generate noise should be fully and In the case of marine noise-generating transparently available for comment before activities, independent peer-reviewers plans are submitted for approval to should include species experts, regulators (DiMento and Ingram 2005; accousticians and expert sound modellers Costanza et al 2006; Sheaves et al 2015). who are able to declare full and verifiable independence from the proposal. Their The Utility of EIAs peer-review reports should be fully transparent and submitted to regulators, Decision makers or regulators are better without influence from proponents. equipped to determine if a proposed activity will impact species of concern in a given Transparency region if thoroughly developed and Finally, transparency is crucial for well- transparent EIAs are presented. They can informed consultation and natural justice. request additional information, make their Noise-generating activities may have wide- own assessment about the cumulative ranging impacts on the environment, impact of the proposed activity with other affecting many different groups in society. pre-existing activities in the region; Genuine consultation has two key consider the timing and the equipment components: participation in the outcome of used. Their decisions can be informed and a decision and that the burden of proof rests based on solid information. with the proponent. To satisfy the burden of For instance, if a noise-generating activity proof, the proponent must provide sufficient was proposed for the Hellenic Trench, and evidence to demonstrate that there is the expert modelling indicated the noise limited danger of damaging the marine propagation would extend into critical environment or any species that have been habitat for Mediterranean monk seals and highlighted as having importance. The Cuvier’s beaked whales (see illustration 1), principle of natural justice, in turn, there would be justification for restricting enshrines a right to a fair hearing so that and/or rejecting that proposal. individuals are not unfairly impacted (penalized) by decisions that affect their Alternatively, if a noise-generating activity rights or legitimate expectations (DiMento was proposed for the Strait of Sicily, and the and Ingram 2005; O'Faircheallaigh 2010; expert modelling within the EIA indicated Glasson et al 2013). the noise propagation would extend into a noise-cetacean interaction hotspot in the This principle is already in use in the United ACCOBAMS area (see illustration 2), there States (US), where applications for marine would be justification for restricting and/or noise-generating activities that might harm rejecting that proposal. species protected under US law, including naval activities, require a transparent public There is solid international agreement that consultation process. Elsewhere in the EIAs should be conducted. The detail of world, including European States, naval what should be requisite is known and activities frequently evade such available. What is needed is a change of practice: by regulators to insist thorough

68 EIAs are presented, and by proponents to advancement of environmental impact accept the same. Only then will there be assessment theory. Impact Assessment and appropriate assessment of anthropogenic Project Appraisal. 22, 4: 295-310. noise in our oceans. Only then will we move CBD. 2006. Decision VIII/28: Impact assessment: from paper to practice. Voluntary guidelines on biodiversity- inclusive impact assessment. Curitiba, Brazil, References 8th Conference of the Parties to the Convention on Biological Diversity. ACCOBAMS. 2010. Resolution 4.17: Guidelines to CBD. 2014. Decision XII/23: Marine and coastal address the impact of anthropogenic noise on biodiversity: Impacts on marine and coastal cetaceans in the ACCOBAMS area. Monaco, 4th biodiversity of anthropogenic underwater Meeting of the Parties to the Agreement on noise and ocean acidification, priority actions the Conservation of Cetaceans in the Black to achieve Aichi Biodiversity Target 10 for Sea Mediterranean Sea and Contiguous coral reefs and closely associated ecosystems, Atlantic Area. and marine spatial planning and training ACCOBAMS. 2013. Resolution 5.13: Conservation initiatives. Pyeongchang, Republic of Korea, of Cuvier's beaked whales in the 12th Conference of the Parties to the Mediterranean Tangier, Morocco, 5th Meeting Convention on Biological Diversity. of the Parties to the Agreement on the Clay, CS. and Medwin, H. 1997. Acoustical Conservation of Cetaceans in the Black Sea Oceanography. New York, Wiley Interscience Mediterranean Sea and Contiguous Atlantic Area CMS. 2008. Resolution 9.19 – Adverse Anthropogenic Marine/Ocean Noise Impacts ACCOBAMS. 2013b. Resolution 5.15: Addressing on Cetaceans and Other Biota. Rome, Itlay, 9th the impact of anthropogenic noise Tangier, Conference of the Parties to the Convention Morocco, 5th Meeting of the Parties to the on Migratory Species of Wild Animals. Agreement on the Conservation of Cetaceans in the Black Sea Mediterranean Sea and CMS. 2011. Resolution 10.24: Further Steps to Contiguous Atlantic Area Abate Underwater Noise Pollution for the Protection of Cetaceans and Other Biota Aguilar de Soto, N. and Kight, C. 2016. Bergen, Norway, 10th Conference of the Physiological effects of noise. Ch. 8 in Solan, Parties to the Convention on Migratory M. and Whiteley, N. (Eds) Stressors in the Species of Wild Animals. Marine Environment. Physiological and Ecological Responses and Societ al Costanza, R., Wilson, MA., Troy, A., et al. 2006. Implications. Oxford University Press. 350 pp The value of New Jersey's ecosystem services and natural capital. Portland, Institute for André, M., Morell, M., Alex, M., et al. 2010. Best Sustainable Solutions, Portland State practices in management, assessment and University control of underwater noise pollution. Barcelona, Laboratory of Applied Devlin, JF. and Yap, NT. 2008. Contentious Bioacoustics (LAB), Technical University of politics in environmental assessment: Catalonia (UPC) blocked projects and winning coalitions. Impact Assessment and Project Appraisal. 26, Bern Convention. 1979. Berne Convention on the 1: 17-27. Conservation of European Wildlife and Natural Habitats, Bern. DiMento, JFC. and Ingram, H. 2005. Science and environmental decision making: the potential Calambokidis, J., Chandler, T. and Douglas, A. role of environmental impact assessment in 2002. Marine mammal observations and the pursuit of appropriate information. Nat. mitigation associated with USGS seismic- Resources J. 45: 283-309 reflection surveys in the Santa Barbara Channel 2002. Final report prepared for US Espoo (EIA) Convention. 2014. Geological Survey, Menlo Park, CA & National ECE/MP.EIA/SEA/2014/2: Good practice Marine Fisheries Service. In Office of recommendations on public participation in Protected Resources. Silver MD, strategic environmental assessment. Geneva, th Prepared by Cascadia Research, Olympia, WA Economic and Social Council/6 Meeting of the Parties to the Espoo (EIA) Convention. Cashmore, M., Gwilliam, R., Morgan, R., et al. 2004. The interminable issue of Etter, PC. 2012. Advanced applications for effectiveness: substantive purposes, underwater acoustic modelling. Advances in outcomes and research challenges in the Acoustics and Vibration, Article ID 214839, 28 p.

69 Etter, PC. 2013. Underwater acoustic modeling Morrison-Saunders, A. and Retief, F. 2012. and simulation. Boca Raton: CRC Press, Walking the sustainability assessment talk— Taylor & Francis Group Progressing the practice of environmental EU. 1992. Council Directive 92/43/EEC on the impact assessment (EIA). Environmental conservation of natural habitats and of wild Impact Assessment Review. 36: 34-41. fauna and flora; NOAA. 2016. Technical Guidance for Assessing EU. 2010. Council and European Parliament the Effects of Anthropogenic Sound on Directive 2009/147/EC on the conservation Marine Mammal Hearing: Underwater of wild birds Acoustic Thresholds for Onset of Permanent and Temporary Threshold Shifts. U.S. Dept. of European Commission. 2007. Guidelines for the Commerce, NOAA. NOAA Technical establishment of the Natura 2000 network in Memorandum NMFS-OPR-55, 178 p. the marine environment: Application of the Habitats and Birds Directives O'Faircheallaigh, C. 2010. Public participation and environmental impact assessment: Farcas, A., Thompson, PM. and Merchant, ND. Purposes, implications, and lessons for public 2016. Underwater noise modelling for policy making. Environmental Impact environmental impact assessment. Assessment Review. 30, 1: 19-27. Environmental Impact Assessment Review. 57: 114-22. Popper, AN. and Fay, RR. 2011. Rethinking sound detection by fishes. Hearing research, 273(1), Glasson, J., Therivel, R. and Chadwick, A. 2013. pp.25-36. Introduction to environmental impact assessment. London: Routledge. Prideaux, G. and Prideaux, M. 2015. Environmental impact assessment guidelines Hawkins, AD. 1986. Underwater sound and fish for offshore petroleum exploration seismic behaviour. The Behaviour of Teleost Fishes surveys. Impact Assessment and Project Springer, pp. 114-151 Appraisal. published online December 2015. Hildebrand, JA. 2009. Anthropogenic and natural Sheaves, M., Coles, R., Dale, P., et al. 2015. sources of ambient noise in the ocean. Marine Enhancing the Value and Validity of EIA: Ecology Progress Series. 395, 5: 5–20. Serious Science to Protect Australia's Great IMO. 2013. Resolution A.1061(28):High-level Barrier . Conservation Letters: n/a-n/a. Action Plan of the Organization and Priorities Southall, BL., Bowles, AE., Ellison, WT., et al. th for the 2014-2015 Biennium. London, 28 2007. Marine mammal noise-exposure Assembly of the International Maritime criteria: initial scientific recommendations. Organsiation. Bioacoustics. 17, 1-3: 273-75. Jay, S., Jones, C., Slinn, P. and Wood, C. 2007. UNCLOS. 1982. United Nations Convention on Environmental impact assessment: the Law of the SeaMontego Bay. Article 206 Retrospect and prospect. Environmental Impact Assessment Review. 27, 4: 287-300. Urick, RJ. 1983. Principles of Underwater Sound. New York: McGraw-Hill Co. Lurton, X. 2010. An Introduction to Underwater Acoustics: Principles and Applications. Wagstaff, RA. 1981. Low‐frequency ambient Westport: Springer. noise in the deep sound channel—The missing component. The Journal of the McCauley, RD., Fewtrell, J., Duncan, AJ., et al. Acoustical Society of America. 69, 4: 1009-14. 2000. Marine seismic surveys–a study of environmental implications. APEA Journal: Weir, CR. and Dolman, SJ. 2007. Comparative 692-708. Review of the Regional Marine Mammal Mitigation Guidelines Implemented During Morley, EL., Jones, G. and Radford, AN. 2014. The Industrial Seismic Surveys, and Guidance importance of invertebrates when Towards a Worldwide Standard. Journal of considering the impacts of anthropogenic International Wildlife Law & Policy. 10, 1: noise. Proceedings of the Royal Society of 1-27. London B: Biological Sciences. 281, 1776: 20132683.

70 Figure 1: Mediterranean monk seal and Cuvier’s beaked whale critical habitats, OceanCare, 2015

Figure 2: Noise-cetacean interactions hotspots, ACCOBAMS Secretariat, 2016

71

CONTROLLING UNDERWATER NOISE FROM SHIPS

Jesse H. Spence & Raymond W. Fischer Noise Control Engineering, LLC 799 Middlesex Tpke., Billerica, MA 01821 [email protected] +1 (978) 670-5339

Abstract (bubble curtains). In the many years since initial attempts were made to reduce noise Underwater noise from vessels is largely from pile driving, advances have been made unregulated, possibly due to a lack of in noise control technology and techniques consensus about the impacts of vessels on ranging from dewatered cofferdam-barriers marine life. However, the technology to press-in piles [2]. required to reduce underwater noise is available today, and can be implemented to There are very few restrictions currently reduce noise by 3-5+ dB at a cost that is placed on underwater noise from vessel approximately 1% of the total cost of the operations, at least with relation to vessel. concerns of impacts to marine life. This may due in part to a lack of consensus about the Introduction impacts of vessel noise on marine life, though it is known that vessels are a major Concerns about the levels of anthropogenic contributor to the rise in low frequency noise in the world’s oceans have risen over noise throughout the world’s oceans as well the past decade. These concerns have been as local impacts in ports, shipping channels, met with efforts to quantify and and other areas where vessel density is characterize sounds produced by vessels, elevated [3]. On the other hand, the control offshore platforms, exploration activities, of underwater noise from ships is an area construction, and the other myriad of that has been studied and implemented for activities that humans perform at sea. many decades. This is primarily a result of Various governmental regulatory bodies are direct military need for quiet vessels. More also working to perform their own long- recently, there has been a drive to design term measurements of underwater noise, and construct quiet research vessels that possibly as a precursor to future regulation. provide scientists with a ‘stealthy’ platform These efforts are important, and provide that minimally affects the behavior of the insights into real-world levels of noise near animals being studied. and far from marine activities. They can also Reducing vessel noise requires a detailed be used for assessments of animal locations, populations, and impacts to marine life as a evaluation of the vessel’s design. Even vessels of a certain type (i.e. tankers, whole. container ships, etc.) contain their own Currently, there is limited regulation of nuances, and while there may be underwater noise. Pile driving is the commonalities in the major noise sources, primary exception; multiple European methods of controlling noise must be countries apply limits to underwater sound implemented by considering those nuances. generation from pile driving, and within the For this reason, there is no one-size-fits-all USA limits are applied for some projects. solution to underwater noise. Rather, each Regulation of pile driving noise was likely vessel design must be acoustically spurred by a combination of immediate evaluated, and then the appropriate noise visual feedback of the acoustic impacts (fish control approaches can be implemented. have been reported to die nearly instantaneously once pile driving starts in Underwater noise generation mechanisms some locations [1]) and the availability of a from vessels are well understood, and noise seemingly effective mitigation method reductions could be implemented today. New vessel constructions would benefit the

73 most, as designing vessels to be quiet is (suction) profile that is specific to the blade generally more effective than retrofitting and the ship. treatments.  Design Costs for such efforts must be considered if The level of noise produced by cavitation is vessel noise is to be made inherently quieter proportional to the amount of cavitation worldwide. It is estimated that for most bubbles that are collapsing during a given commercial vessels, cost increases of time period. Therefore, reducing the amount approximately 1% of the current cost of the of cavitation that occurs will reduce the vessel can be expected for reductions in noise in the water. This can be accomplished noise of approximately 3-5 dB. This includes through modifications to blade geometry, all engineering, manufacturing, material rotation speed, and flow into and out of the procurement, installation, and validation propeller. testing that would be required. Blade geometry has a direct impact on the This paper presents an overview of the pressure distribution over the blade, which major sources of underwater noise from in-turn dictates the degree of cavitation. vessels, and the means of controlling that Many factors can be changed and optimized, noise. Details of cost estimates are also including diameter, number of blades, provided. thickness profiles, camber, pitch, skew, rake, and others. Vessel noise sources and solutions It is the job of the designer to optimize the Propeller Noise blade geometry to create sufficient thrust  Cavitation and Propeller Design Basics while minimizing cavitation. Ideally, the pressure over a large portion of the suction Propellers create cavitation when operating side of the blade would approach the vapor under moderate to heavy loads. Cavitation is pressure threshold, while never crossing it. the generation of vapor bubbles (‘cavities’) This is difficult to do for practical within the water when the pressure is applications, though using this concept reduced below the vapor pressure limit. cavitation can be minimized. (Such a design These bubbles are often visible, especially would never occur if noise impacts were not when cavitation is ‘fully developed’ (i.e. considered.) when there is a lot of it), but can also be present without significant visual cues. The pressure distribution also changes Noise is generated when cavitation bubbles depending on the speed of the water collapse; this is a violent, though small scale relative to the blades, and therefore rotation event that creates noise as well as rate is an important parameter in propeller tremendous heat and even light. design. In general, large, slow-turning propellers will have less cavitation than Understanding how cavitation forms smaller, higher speed propellers. requires a basic understanding of how a propeller generates pressures. When a The flow distribution into the propeller is propeller blade rotates through the water, another major factor in determining the one side creates a suction while the other velocity over the blade, and ultimately in side creates a positive pressure. This results determining the optimal shape for a in a net pressure differential across the propeller blade. In open water, the flow into blade, creating the thrust that propels the the area occupied by the propeller would be ship. A diagram illustrating this principle for uniform. The real operating environment for a 2-dimensional blade cross-section is a propeller is complex, because the flow into presented in Fig. 1. In this figure, the (and out of) the propeller is affected by the cavitation occurs in a specific area on the presence of the vessel and other blade face, though the extent and location of appendages. Specifically, the hull displaces cavitation will depend on the pressure the water in front of the propeller, changing

74 the velocity of water across the propeller The tools for assessing and reducing area in a non-uniform way. machinery noise exist today. Some of these tools have been implemented for decades, An example ‘wake distribution’ is shown in and prediction technology improvements Fig. 2. In this image, the flow is symmetrical are ongoing. Approaches to prediction and about the centerline (left side of the image) treatment optimization include a range of and the semi-circle denotes the area analytically and empirically based occupied by the propeller. The contour lines numerical modelling options. Some of these are boundaries of equal velocity, and the approaches combine fundamental physical values assigned to each contour are ‘wake principles with practical marine noise fractions’ which are analogous to an inverse control experience and are widely used [5]. of flow velocity. This contour is an example Computer programs with 3-D modeling of how flow velocity presented to a environments have also been developed for propeller can vary widely with position. The improved modeling efficiency and accuracy non-uniformity of the wake results in a [6]. position-dependent water velocity relative to the blade. This complicates the process of Costs selecting propeller geometries; a particular geometry will generally be optimized for a The cost of implementing noise reduction particular flow, but if that flow is changing into vessel designs is dependent on the as a function of blade position then there is amount of reduction that is required, among no ‘optimal’ design other than one that many other factors. While this paper does includes many compromises. not attempt to assess what noise reduction is needed, it is believed that a 3-5 dB For these reasons, reducing noise for any reduction is achievable for many vessel requires an understanding of the commercial vessels. wake produced by the vessel, combined with an appropriate analysis of effective When propeller modifications are needed, a blade designs. If performed early in the reduction in thrust may occur for some design, it is possible to combine hull and designs. This should be expected, propeller optimizations using appropriate particularly for large vessels where the numerical and physical modeling tools. propeller has generally been optimized for These tools are currently available and are thrust. However, these reductions would be used in standard practice. minor, estimated to be around 1-2%, and practically speaking would have a small Noise from Machinery impact on vessel operations especially when The magnitude of underwater radiated compared to imposing speed restrictions to noise caused by machinery will vary reduce noise. Machinery treatments depending on the type of machinery, it’s generally increase , though again for location in the vessel, and other factors a 3-5 dB reduction this increase would be relating to vessel design. Vessels with small and should not affect vessel heavily cavitating propellers will often mask operational efficiency. machinery induced noise, with the possible The monetary costs for noise control of this exception of low frequency tones from magnitude are estimated to be between propulsion and power generation $100-500k USD. This would include all equipment. Conversely, machinery noise increases to cost for design, manufacturing, will be the dominant noise source when installation, and verification testing. This propeller cavitation noise is low. would be an increase in cost of around 1% All machinery items produce local vibration for many commercial vessels. Costs will be and airborne noise, which can be lower in cases where noise goals are added transmitted to the hull and radiated into the to propeller design efforts that already water. These paths can be complex, and include detailed analyses to optimize thrust. again require detailed analysis to determine Costs will certainly be on the higher end for the dominant path for any particular design. existing vessels and when implemented as

75 an ‘add-on’; noise control should be built-in References to the design of new vessels at an early stage. [1] M. Hastings, A Popper, “Effects of Sound on Fish,” Prepared for Jones & Stokes and the Conclusions California Department of Transportation, Sacramento, CA, 2005. The vast majority of commercial vessels [2] J. Spence, R. Fischer, M. Bahtiarian, L. have been designed without consideration Boroditsky, N. Jones, R. Dempsey, “Review of for underwater noise, though the Existing and Future Potential Treatments for technology required to reduce noise from Reducing Underwater Sound from Oil and vessels is available today. Noise control Gas Industry Activities,” Noise Control solutions must be designed and Engineering Report 07-001, Prepared for the implemented on a case-by-case basis. The Joint Industry Programme on E&P Sound and development of real solutions can only be Marine Life, December 31, 2007. rd accomplished with an intimate knowledge [3] R. Urick, Principles of Underwater Sound, 3 of pertinent aspects of each vessel. This is Edition, Peninsula Publishing, Los Altos Hills, most cost effective when performed during California, 1983. the vessel’s design stage. Retro-fitting [4] E. V. Lewis, Principles of Naval Architecture, treatments is possible, but results in Volume II, Resistance, Propulsion, and additional costs and design limitations. Vibration, Society of Naval Architects and Marine Engineers, Jersey City, NJ, 1988. Vessels can be designed to be quiet, but to [5] R. W. Fischer, C. B. Burroughs, D. L. Nelson, make a significant impact in local and global “Design Guide for Shipboard Airborne Noise underwater noise there would need to be Control,” Technical and Research Bulletin No definitive noise goals for each vessel. The 3-37, Published by The Society of Naval increase in cost for many commercial Architects and Marine Engineers, New York, vessels would be around 1% of the total cost NY, 1983. of the vessel for a 3-5+ dB reduction relative [6] J. Spence, L. Boroditsky, R. Fischer, T. McNatt, to existing noise levels. G. Hazen, “Advanced Shipboard Noise Engineering System,” Internoise 2004, The rd 33 International Congress and Exposition on Noise Control Engineering, Prague, Czech Republic, August, 2004.

76 Fig. 1: Example pressure distribution over propeller blade, with cavitation area noted [4]

Fig. 2: Example wake distribution showing flow velocity into the propeller [4]. Contour lines correspond to locations of equal ‘wake fraction’ which is analogous to the inverse of flow velocity. Note the wide range of flow velocities.

77

WHAT MEANS TO PROTECT SENSITIVE MARINE MAMMALS FROM PILING NOISE OF OFFSHORE WINDFARMS FOUNDATIONS INSTALLATION?

Rémi Casteras, Rassim Hariz & Yohan Weiller Environment managers at wpd Offshore France

Offshore windfarms (OWFs) have been developed a large variety of methodologies developing for more than twenty years in and devices so that effects of pilling noise is Europe at a still increasing pace. A lot of limited. We propose to discuss here the European countries decided to use it to different means at the disposal of an improve the renewable share of their offshore wind farm developer and energy mix: wind is more consistent understand in which cases they might be offshore and space is less limited than preferably used. onshore, making offshore windfarms an interesting solution for renewable energy 1. An approach dedicated at respecting a specific noise level: noise mitigation development. systems to reduce pilling noise As of June 2016, 3 344 offshore wind 2. Deterrence means focused on taking turbines with a combined capacity of 11 sensitive species away from impacted 538MW are producing electricity in Europe zones (https://windeurope.org/wp-content/uploads/f iles/about-wind/statistics/WindEurope-mid-ye Noise mitigation systems (NMS) ar-offshore-statistics-2016.pdf). More than Several noise mitigation systems have been 80% of these wind turbines are installed on developed to lower pilling noise (figure 2). monopiles driven in the ground by pilling. This installation process is the most The most commonly used are Big Bubble commonly used and can produce high level Curtains (BBC). It consists of rings of of noise depending on monopile perforated pipes positioned on the sea floor dimensions, water depth, soil conditions on around the foundation to be piled out. The site and installation technics (Figure 1 air passes into the water column by LEFT). This part of OWF construction is regularly arranged holes. They can be used recognized as the noisiest one of all with a single pipe or with two to three construction activities (even if driving a layers of pipe, increasing the sound monopile into the ground can last only a few insulation. Depending on site characteristics hours in some cases) and a legal issue in (current, water depth, soil conditions etc.) many European countries. For impulsive and on project parameters (type and sounds biological impact measurement the diameter of foundation, hammer and indicator Sound Exposure Level (SEL) is in installation boats) bubble curtains can use. It is a level of acoustic exposure achieve a noise reduction from 10 to 18 dB perceived by an animal, a representation of SEL broadband (Bellmann 2014). It usually noise accumulation received by a receptor permits a little decrease in Sound Peak over a period. Noise spectrum of pile driving Levels (SPL) noise. is usually between 50 Hz to 16 kHz (Figure 1 RIGHT). This underwater noise Another noise mitigation system is the can impact marine life and more specifically Hydro Sound Damper (HSD). It consists of a marine mammals either as injury or as fisher net where foam plastic or gas-filled disturbance as they are high sensitive balloon of different sizes are included. This species, usually having a large frequencies fisher net is ballasted by a weighted ring hearing range. allowing its good deployment around the foundation. The radiated noise from the pile To prevent and minimize impacts on marine will be reduced by the absorption-reflection mammals, offshore wind industry has of HSD elements. HSD system can reach a

79 noise reduction of 8-13 dB SEL broadband important as bubbles are driven away and (Bellmann 2014) depending on the number pipes have difficulties to be stabilized on the and type of HSD elements in the fisher net. ground. IHC has developed a specific NMS, the so Unfortunately as each project has its own called IHC tube consisting of a double-wall characteristics (depth, current, soil steel screen (tube) where monopile is conditions, pile diameter, etc…), each inserted inside the system. Space between combination of NMS was not established a the two screens is filled with air and air priori but after a certain time of testing and bubbles can be feed-in between pile and adjustment at the beginning of each project NMS system. The radiated sound crosses the installation. Therefore it is difficult to internal bubble curtain as well as the air- establish a standard NMS working for every filled double-wall steel screen and will be project: it needs time to find the right and reduced due to reflection (impedance gap). adapted combination. Another important In situ measurements showed this tool may aspect is that NMS are still under lead up to 43dB reduction in certain development and their reliability is still frequencies (IHC presentation at 3rd increasing: some progress is still awaited for workshop of “Racket in the Oceans” on the future projects. These solutions can 17th of May 2016 in Paris). An alternative represent 10% of the installation costs for quite similar to IHC’s NMS is the cofferdam: foundations, and have to be diminished it consists of a single wall tube put around since the industry is fighting to have a the foundation and full of air. The pile is competitive LCOE. then installed “in air” and the sound of pilling is first transmitted to the air before Deterrence means take marine getting transmitted into the water after mammals away from impacted zones transiting through the steel screen. Impendence differences between the two In some countries (Denmark, United will make the sound reflect and decrease it. Kingdom, France) there is no legal limit to In order to make Cofferdams work properly, noise levels. The law anyway requires to a good gasket needs to be put so that the take into consideration the sensitivity of space between pile and steel tube can be each species of marine mammals located in filled with air. This operation can be quite the construction area during the initial state complicated and difficult to set in offshore of the environmental impact assessment. conditions. If it is done properly, a decrease This “species driven” approach uses of up to 20dof SEL broadband can be deterrence means to be sure that marine achieved (Bellmann 2014). mammals will not be present in sectors where physical damages of hearing may All these noise mitigation systems have occur. Mammals usually flee from noisy been developed to comply mainly with sectors far before the noise reaches the level German regulations fixing certain limit to of temporary injury (TTS for Temporary sound emission levels. For example noise Threshold Shift) or permanent injury (PTS should be limited at 160dB SEL or 190 dB for Permanent Threshold Shift). For SPL at 750m from piling location in instance, harbour porpoises detections Germany, 185 dB SPL in Belgium, 160-170 clicks were observed to decline significantly dB in the Netherlands with periodical before any pilling or use of deterrence restrictions. Those noise limits may not be measure to distances of up to 10 km, perfectly adapted to all marine mammal probably due to an increase in shipping species and were mainly directed at seals activity related to preparation works and harbour porpoises. NMS can be (Miriam J. Brandt et. al., 2016). combined and in many recent OWFs of German EEZ, they were combined in order Several tools have been developed to chase to comply with the 160 dB limit (Figure 1 away sensitive marine mammals and to RIGHT). Each of these NMS have also their avoid any physical damage. own limits and constraints. For example BBC are poorly working when current is too

80 Soft starts improve the efficiency of these deterrence system (Nehls et al, 2015). A first way of mitigating the effects of the noise generated, is to begin the piling Conclusion sequence with a gradually increasing energy level, this procedure being termed a "soft We presented in this article different start". The mammals have time to flee away solutions that help minimize pile driving from the PTS and TTS sectors. Robinson et noise and prevent biological impacts related al. (2007) for example described precisely to OWF construction. Some key questions the piling sequence (from 80 kJ to 800 kJ) regarding these solutions employment are: and measured the consequent increase of the noise level (+12 dB peak to peak).  Is the solution adapted to the site conditions (depth, current, soil, but also Seal-scarers or pingers hearing sensitivity of species present on site)? It was first a need for offshore aquaculture  What costs each solution would to chase away seals from production represent and what implementations facilities and decrease their predation on constraints would it add (ie extra boat, farmed fish. This was allowed by the use of additional standby due to meteo-oceanic seal-scarers or pingers . These devices are conditions, boat mobilization time acoustic repellent. However, seals were increase, etc.) shown to habituate quickly to these  What regulatory constraints do I have to deterrence devices and could even lead to a comply with? “dinner bell” effect (Brandt et al. 2013).  Is the solution I am going to use reliable With regards to OWFs, seal-scarers have (as a lot of research and development are still ongoing and some solutions have proven their efficiency also for harbour been used only in experimental porpoises, scaring them away at up to 7.5km conditions)? from deterrent device (Brandt et al. 2013). There is no “turnkey” solution neither Even though scientific evidences are lacking perfect “state-of-the-art” solution. Each for the efficiency of these deterrence project needs a specific evaluation, based on systems, many different studies (Dähne et an initial state to determine which species al. 2013) showed that mammals are usually are present in the area, and on economic scared away from windfarms during and technical assessment of mitigations that construction. Presence of mammals may be can be put in place. modified until 22 km from piling workshop (Degraer et al., 2013). This distance is References significantly higher than the distance where BELLMANN Michael A (2014) Overview of injuries (PTS - TTS) can occur, for example existing Noise Mitigation Systems for 2.3 km in Southall and al. 2007. Marine reducing Pile-Driving Noise - Inter-noise mammals observers (MMO) have been 2014 classically used in United Kingdom to https://www.acoustics.asn.au/conference_pro monitor if a mammal is too close to noisy ceedings/INTERNOISE2014/papers/p358.pdf workshop as for example seismic surveys BRANDT Miriam J., HÖSCHLE C., DIEDERICHS A., (JNCC, 2010). But detection range of the BETKE K., MATUSCHEK R., WITTE S. and MMO for small mammals may be below the NEHLS G. (2013). Far-reaching effects of a impact range. For instance, maximum seal scarer on harbour porpoises, Phocoena detection range estimated by Leaper and al. phocoena. Aquatic Conserv: Mar. Freshw. (2015) for Harbour (Phocoena Ecosyst. 23: 222–232 phocoena) is 358 meters in the North Sea DÄHNE, M., GILLES, A., LUCKE, K., PESCHKLO, V., conditions. Real time monitoring of the ADLER, S., KRÜGEL, K., ... & SIEBERT, U. presence of the mammals through (2013). Effects of pile-driving on harbour hydrophones and adapting piling strategy to porpoises (Phocoena phocoena) at the first the monitoring (i.e. interrupt piling if an offshore wind farm in Germany. Environmental Research Letters, 8(2), animal is detected in the impacted area) can 025002.

81 DEGRAER, S., BRABANT, R., & RUMES, B. (2011). Reduce the Risk of Injury from Loud Sound Offshore wind farms in the Belgian part of the Sources. Aquatic Mammals 2015, 41(4), North Sea. Royal Belgian Institute of Natural 375-387 Sciences Management. Unit of the North Sea NEHLS G., HÖSCHLE C., KOSAREV V., BRANDT Mathematical Models, Miriam J., DIEDERICHS A. (2015). Real-time Management Section. monitoring of harbour porpoise activity Miriam J. Brandt et.al., 2016. Effects of offshore around construction sites using the wireless pile-driving on harbour porpoises abundance detection system (WDS) – RAVE Conference in the German Bight (2009-2013). 2015 https://www.researchgate.net/publication/3 ROBINSON, S. P., LEPPER, P., & ABLITT, J. (2007). 04624972_Effects_of_offshore_pile_driving_o The measurement of the underwater n_harbour_porpoise_abundance_in_the_Germ radiated noise from marine piling including an_Bight_2009_-2013 characterisation of a" soft start" period. In JNCC (2010). JNCC guidelines for minimizing the Oceans 2007-Europe (pp. 1-6). IEEE. risk of injury and disturbance to marine SOUTHALL, B. L., BOWLES, A. E., ELLISON, W. T., mammals from seismic surveys FINNERAN, J. J., GENTRY, R. L., GREENE Jr, C. http://jncc.defra.gov.uk/pdf/JNCC_Guideline R., ... and TYACK, P. L. (2007). Marine s_Seismic%20Guidelines_Aug%202010.pdf mammal noise-exposure criteria: initial LEAPER R., CALDERAN S., and COOKE J. (2015) A scientific recommendations. Bioacoustics, Simulation Framework to Evaluate the 17(1-3), 273-275. Efficiency of Using Visual Observers to

82 Figure 1: LEFT – Measured Peak Level (Lpeak) and broadband sound exposure levels (SEL50) during pile driving work at diverse OWFs as a function of pile diameter measured by ITAP. (Michael A. Bellmann 2014). RIGHT – spectra of noise mitigation at OWF Sandbank with different NMS

Figure 2: Types of Noise mitigation systems (after Dr. Eva Philipp)

83

ADDRESSING UNDERWATER NOISE IN MARITIME PROJECTS: IMPORTANCE, CONTROL AND MITIGATION AND FUTURE PERSPECTIVES

Aleyda Ortega & Henk van Vessem Research Engineer & Technical Accountmanager, Royal IHC

Importance of the issue for the In Europe countries such as Germany, maritime industry Belgium and the Netherlands have established regulations with limit values for The increase of anthropogenic activity at the pile driving induced underwater noise. seas and oceans intensifies the pressure on marine ecosystems. Worldwide there is a The need for maritime operating growing need for protection and companies to address underwater conservation of the marine life. Maritime noise activities such as marine traffic; surveying and exploitation of mineral and For operators, it is important to understand hydrocarbon resources; marine and manage the footprint from their construction and the installation of offshore projects. For technology providers it is renewable energy projects generate marine important to recognize the source of the pressures and can particularly increase noise and to understand its characteristics. underwater noise. Not only the noise This constitutes the basis for the design of generated by specific anthropogenic control measures or avoidance from the activities has been recently studied, there is source. In maritime projects, a noise source also increased knowledge on the marine could be a specific system or a specific sounds emitted by different species and the component of a vessel or the operation of ways marine fauna use sound for auxiliary equipment according to the type of communication and survival. project. The source levels are also depending on the environment where a On regulations and standards, the European project takes place. The impact on specific Marine Strategic Framework Directive fauna depends on those factors as well as on (MSFD), adopted in 2008, requires member the resilience and adaptation of specific states to monitor the environment and to marine fauna. Understanding these implement measures to achieve good variables allows for better planning of environmental status by 2020. Qualitative projects, execution, adaptive planning and it descriptors for good environmental status provides the basis for the design of control include underwater noise. The MSFD states and mitigation measures at the noise source. ‘introduction of underwater noise does not adversely affect the ecosystem’ (European Pile driving for renewable energy projects Commission, 2016). International standards generates high energy sound pressure are currently in development for pulses that could potentially exceed safe underwater acoustics and for marine sound levels for specific marine species. In technology. ISO, for example, has two response to this, Germany, Belgium and The committees on these issues (Audoly et al., Netherlands, for example, have opted to 2016). establish stringent limit values for Sound Pressure Levels (SPL) as well as for Sound The rapid development of offshore wind Exposure Levels (SEL) generated by pile farms at sea requires pile driving for the driving. Compliance with European foundations of the wind turbines in thresholds have been a main driver for the relatively shallow waters. Some development of noise mitigation methods. classification societies have published rule notes with their recommended measurement procedures and limit values.

85 Noise Mitigation System for pile outer screen is a compartment which can be driving: technology and development filled with air. To prevent transfer of trajectory vibrations, rubber cushioning blocks and a seal are installed between the inner and The offshore wind farm construction outer screens. This gap is filled with projects have different type of installations minimum airflow. Inside the NMS a multi- according to the project circumstances and level and multi-size bubble injector system needs. Those can be: mono piles; tripods; is used to optimize the bubble mixture and tension legs; spar and spread moored; etc. therefore, the mitigation system according The installation of mono piles requires pile to local circumstances and water depth. driving. Worldwide, mono-pile installation Several places on the inner and the outer projects currently occur at water depths of screen are prepared for placement of up to 45 m with pile diameters from 1.5 m sensors e.g. for measuring of pressure and up to 7.60 m. acceleration. Germany established strict legislation on The design and optimization of the system underwater noise for the protection of the requires handling of offshore condition marine environment, particularly focused challenges such as weather windows, sea on the protection of the ‘harbour porpoise’. state including waves and currents and Harbour porpoises as well as seals are handling of equipment on board. A ‘Guiding endangered species in German sea waters. Tool’ was designed for the installation of the For this, the limits stablished are maximum NMS. This tool is used to launch the NMS 160 dB SEL05 and 190 dB SPL(peak) and to correct the inclination of the mono measured at 750 m from the pile pile during its installation. To be successful, installation. Belgium has stablished a the NMS must effectively reduce maximum SPL noise level of 185 dB. The underwater noise and its installation and Netherlands has established specific retrieval must be both efficient in time and installation windows (three periods of time cost savings. Cost savings have been during the year) and has defined specific achieved by for example, speeding up the SEL levels that vary according to the installation sequence by using inclination number of turbines to be installed. devices and GPS. The tested inclination devices are widely known and accepted, IHC has developed the ‘Noise Mitigation eliminating the costs from warranty System (NMS) in a research and surveyors during installation. Another way development (R&D) trajectory that has of cost savings is by accurate positioning started in 2007 with the initial planning and and inclination which reduces the collaboration with research institutes and penetration depth and therefore the pilling the Delft University of Technology. Design, time. Also, limited human interference construction and dedicated monitoring of during installation reduces pilling time, and the performance of the NMS during the therefore improving cost savings. installation of several offshore wind projects have generated specific knowledge The NMS has been used in projects in for the development of the mitigation Germany such as Riffgat, Riffgrund, system and its optimisation. Although the Butendiek OWF, Amrumbank, Gode Wind development of a noise mitigation system and Nordsee One. Results achieved during was a sustainability objective within the full scale offshore tests have confirmed R&D trajectory, the compliance with the compliance of pile driving with the NMS European legislation thresholds has with legislation in Germany, Belgium and provided insight on the specific SEL and SPL The Netherlands. A reduction of up to 45 dB levels to be achieved. is achieved in the frequency band from 10 Hz to 20 kHz (approximate hearing range of The Noise Mitigation System consists of a harbour porpoises and seals). Results show double wall steel casing, with stiffeners to that when reaching the 160 dB SEL05 level, reduce water pressure, currents and wave a parallel maximum SPL level reaches 180 impact. The gap between the inner and dB.

86 The design of the NMS depends on the the limit. For this project an additional variations in water depth, location, seafloor bubble screen around the NMS was conditions, weather conditions, diameter of installed. mono piles, hammer size/, whether the pile is a running or a fixed pile, water Current developments and future temperature, sea level and waves, among perspectives others. Other conditions include the background underwater noise. In the North The first versions of the Noise Mitigation Sea, the background underwater noise is System are the NMS-6900, -6000, -6500 and approximately 100-110 dB depending on -8000, these vary on diameter and size sea traffic conditions. It has been measured according to pile hammer specifications as that rain can increase the background noise well as environmental conditions such as level up to 15 dB. The total background water depth. The experience and knowledge noise before pile driving and including the gained during the development and testing installation vessel in stand-by can be of the system have been used for the design approximately 130-140 dB. of the next generation NMS versions and have provided future market directions. Use of additional methods: e.g. Results from monitoring demonstrate that deterring systems and bubble screens 95-100% of the water-borne noise from pile driving can be mitigated by the NMS. In some projects, the standard mono pile However, full scale tests have shown that installation procedure starts with the over when using the NMS the ground-borne boarding of the mono pile and with the noise, transferred from the pile into the positioning on the seabed and activation of seabed and from the seabed into the water the deterring system for marine fauna (e.g. column, is still an important noise source. seal scare and ping devices). Deterring This is currently the main challenge for systems are usually activated for 30 minutes further research and design of control prior to the start of piling. Piling starts with measures. Specialized modelling (Novicos) a soft blow, the soft blow is repeated each has been done to further understand this 30 seconds with limited energy during 30 process (Kringelum et al., 2015). Modelling minutes. Once the starting operation is results also showed the effectiveness of the completed, the energy can be gradually installation of a bubble curtain around the increased up to effective pile driving NMS in reducing the ground-borne noise (standard pile driving frequency is in the and its propagation into the water. order of 40 blows per minute). Sea deterring systems are then turned off. These insights have been key for the Measurements on site have shown that the development of a complementary mitigation use of deterring systems might not be measure to the NMS, the ‘Royal Umbrella required as similar frequencies are reached Noise Mitigation System’ RUNS. The system at the start of pile driving. See Figure 1. is situated on hinges at the lower part of the NMS structure. The bubble curtain consists Figure 2 shows the SEL and SPL levels of two hoses which create a total bubble achieved by the NMS (without additional curtain around the NMS at a radius of bubble screen) at the Riffgrund project for a approximately 30 m. This integrated system specific pile installation. For the complete eliminates the use of an additional ‘external’ installation project, less than 1% of the bubble curtain, which requires a dedicated blows exceeded the 160 dB (SEL05) vessel for installation, large crane capacity threshold. Additional bubble screens and dedicated personnel for launching, surrounding the pile driving and the NMS operation, and recovery. The integration of may be used as a complementary mitigation a bubble system within the NMS measure. The project Butendiek OWF, was significantly reduces operational costs and situated in the German nature reserve area project risks while a reduction of the carbon ‘Natura 2000’ and required an additional footprint for the project is also achieved. measure to maintain the noise levels under

87 Current developments aim to optimise the References RUNS and the NMS. Software and design adaptations are required for the Audoly, C., & Robinson, S. (2016). International optimisation through real-time monitoring. standards for underwater acoustics. This provides the possibility for immediate European Commission. (2016, June). Environment. intervention if noise levels are exceeded. Retrieved from Marine and Coast: The main objectives are to reduce the pile http://ec.europa.eu/environment/marine/g ood-environmental-status/ installation time; reduce impact energy and noise levels. An installation method called ISO. (2016). Standards. Retrieved from ISO/DIS HiLo consisting of high frequency (increased 18406: http://www.iso.org/iso/catalogue_detail.htm blow rate) and low energy (use of minimum ?csnumber=62407 energy required to break the soil resistance) has demonstrated important reduction in Kringelum, J. V., Lippert, S., Heitmann, K., Smidt noise generation. Real-time monitoring Lüen, R., & Skjellerup, P. (2015). The use of numerical modelling to assist and improve provides large amounts of data that are industrial understanding of underwater used for planning and adaptations in future noise and relevant mitigation measures. operations and for product development. Euronoise 2015. Maastricht: European Acoustics Association. Underwater noise in oceans and seas is currently an important issue. Scientific Norro A.M., Rumes B., Degraer S.J. (2013). research has provided more insight on the Differentiating between Noise of Monopile and Jacket adverse effects that underwater noise can Foundations for Offshore Windmills: A Case have on marine ecosystems. Also, European Study from the Belgian Part of the North Sea. regulations and standards have been an The Scientific World Journal, pp. 1-2, 4,-6. important driver for the development of Saleem Z., (2011). “Alternatives and modifications technology that minimises underwater of Monopile foundation or its installation noise during pile driving of offshore wind technique for noise mitigation”. TU Delft farms. Other drivers are cost savings and Report, TU Delft University, pp. 12-15. the reduction of the environmental footprint Van der Graaf A.J., Ainslie M.A., André M., during installation of the mono piles. Pile Brensing K., Dalen J., Dekeling RPA., Robinson driving methods and noise mitigation S., Tasker M.L., Thomsen F., Werner S. (2012). measures are primarily dependent on the "European Marine Strategy Framework design and specifications of the wind Directive - Good Environmental Status (MSFD turbines to be installed. Today larger wind GES): Report of the Technical Subgroup on turbines are being developed to serve the Underwater noise and other forms of deeper sea areas and therefore demanding energy", pp. 3, 11-13, 14, 17-19, 20. adapted piling methods and systems.

88 Figure 1: Measured noise levels in Riffgrund project. Backgound noise (purple); Piling noise level with and without NMS (light green and orange, respectively); hearing range for harbour porpoise (blue) and seal scarer device (red). Source Royal IHC

Figure 2: NMS-6000 Riffgrund project. Noise results for Pile 15. Pile driving at reduced energy conditions. Max. 59 blows/min. Measurements using only the NMS-6000 without an additional bubble curtain. Source: Royal IHC

89

THE ENHANCING CETACEAN AND HABITAT (ECHO) PROGRAM: A PORT AUTHORITY- LED COLLABORATIVE INITIATIVE WORKING TO REDUCE CUMULATIVE NOISE IMPACTS OF COMMERCIAL VESSEL ACTIVITY ON AN ENDANGERED KILLER WHALE POPULATION

Orla Robinson ECHO Program Manager, Vancouver Fraser Port Authority, Vancouver, British Columbia, Canada

Background Context ECHO program description and goals The west coast of British Columbia, Canada The ECHO program is a Vancouver Fraser is a dynamic and growing international Port Authority-led collaborative initiative trade gateway. It is also a productive coastal aimed at better understanding and ecosystem that sustains populations of managing the impact of cumulative shipping whales, porpoises and dolphins (cetaceans). activities on at-risk whales throughout the Fisheries and Oceans Canada (DFO) has southern coast of British Columbia. A suite published Species at Risk Act recovery of individual short-term projects, scientific strategies and action plans for a number of studies and educational initiatives are being at-risk whale species in the region. Some of advanced by the ECHO program. Between the key identified threats to whales in this now and 2018 it is intended that these region include: acoustic disturbance, projects will fill knowledge gaps around physical disturbance), environmental vessel-related cumulative regional threats contaminants, and the availability of prey. and will inform the development of mitigation solutions, threat reduction Much of the commercial vessel activity in targets and management options. The long- the southwest coast of Canada transits DFO- term goal of the program is to quantifiably designated critical habitat for endangered reduce threats from commercial vessel- southern resident killer whales, as well as related activities to at-risk whales. areas known to be of importance to other at-risk whales. Currently, the population of A collaborative approach southern resident killer whales is just 84 individual whales. These iconic whales have Launched in November 2014, the ECHO cultural significance for First Nations and all program aims to engage and involve key Canadians. The human population of the regional interests to maximize program Metro Vancouver area, currently 2.3 million success and help ensure that mitigation and people, is predicted to grow by one million management measures developed through people by 2040, and with increased trade the program are informed by social, cultural, demands and a number of potential marine economic and environmental interests. projects coming on line in Canadian and Stakeholders include scientists, maritime American waters, commercial vessel traffic industries, conservation groups, First through southern resident killer whale Nations individuals and government designated critical habitat is predicted to agencies - who collectively set goals and increase over the same time. objectives and help focus program efforts. Along with a core Advisory Working Group, Vancouver Fraser Port Authority is an Acoustical Technical Committee was committed to ensuring port activities are established to provide technical and undertaken in a responsible and sustainable scientific advice in the development and manner that safeguards and promotes execution of ECHO research, mitigation and continual protection of the environment. management projects and is composed of For these reasons, the Enhancing Cetacean marine mammal biologists, acousticians, Habitat and Observation (ECHO) program naval architects and others with specific was developed. technical knowledge around the sources and

91 impacts of underwater noise. The ECHO Canada to install an underwater listening program is also an end-user to a number of station in the Strait of Georgia on the national and international underwater noise approach to the Port of Vancouver. The research projects, including the AQUO listening station is comprised of JASCO Project. Autonomous Multi-channel Acoustic Recorders (AMAR) 4 element hydrophone Projects and studies to inform arrays and is located at 173m, beneath the mitigation and regional inbound shipping lane. The system is management – Acoustic disturbance connected to ONC’s cabled Venus Observatory and is designed to approximate Through consultation with the Advisory as closely as possible to ANSI/ASA S12.64- Working Group and Acoustic Technical 2009/Part 1 standard for measuement of Committee, an acoustic work plan was vessel underwater radiated noise. developed and a number of research projects have been initiated which aim to fill Working with local vessel pilots, the ECHO specific data gaps and enhance program is encouraging as many understanding of regional cumulative vessel vessels as possible to accurately transit the noise impacts. These projects include the underwater listening station. For each following, some of which are highlighted in vessel that correctly transits the more detail below: measurement zone an automated vessel source level report will be generated which  Strait of Georgia underwater listening includes monopole and radiated noise station levels; frequency M-weighted (low, mid and  Regional acoustic model and high frequency cetaceans) vessel noise identification of vessel noise contributors emission levels and an “in class” vessel to noise budget performance ranking. The PortListen  Regional ambient noise monitoring software (See Figure 1) developed by JASCO network allows ECHO program staff to review which  Development of a port incentive program vessels have accurately transited the for quieter vessels listening station, view and listen to the  Comparison of behavioural response of vessel sound signature, and generate a killer whales to shipping vs. whale watch vessel noise report which can be provided to the vessel owner.  Investigation of the effects of ship noise on vocal behaviour of humpback whales As the listening station is continually  Development of an infographic on recording underwater noise, the sound underwater noise and delivery of measurements obtained are also being used educational seminars to vessel to generate an ambient noise report for each owners/operators lunar month, as well as a monthly marine The ECHO Program is using the outputs of mammal occurrence report. these acoustic science research projects to help stakeholders better understand and The outputs of the underwater listening take action on the issue of acoustic station will be further used to: disturbance, to inform science based  Help vessel owners/operators decision making and to inform the understand vessel noise levels and development of vessel noise reduction performance in class and identify solutions. potential mechanical problems  Inform the development of potential Regional Management Applications. incentive or recognition programs for Project highlight – Strait of Georgia quieter vessels Underwater listening station  Test potential vessel noise reduction options e.g. hull cleaning, speed The ECHO program has partnered with variations Ocean Networks Canada (ONC), JASCO  Build comprehensive vessel source level Applied Sciences Ltd (JASCO) and Transport database

92  Refine vessel source level measurements how underwater noise may differ if vessels for future noise modelling were to be re-routed, slowed down, if traffic were to increase due to a specific project, or Regional Management Applications. if the mix of vessel sizes and categories Project highlight – Regional acoustic transiting the region were to change in the modelling and noise budget future.

An acoustic model has been developed by Global Applications JASCO which captures the region where vessel transit routes overlap with southern The Vancouver Fraser Port Authority is resident killer whale critical habitat (see taking a proactive approach to maintain a Figure 2). The region is represented on a healthy ecosystem within a busy and computational grid, with shipping density prosperous marine gateway. specified at each grid point through the use of AIS tracks. According to the vessel The ECHO program aims to enhance category and speed, a vessel noise source understanding of the cumulative impacts of level is applied to each vessel at each grid shipping on whales in this region and to point, and noise transmission to develop voluntary mitigation measures and surrounding grid locations is calculated incentives for vessels owners and operators using a sound propagation model. The to reduce those impacts. As the issues propagation model takes into account the around underwater noise gain momentum water depth, the sea bottom type and the within the global shipping industry, the water sound speed profile. science and solutions being developed by the program may see global application. Using this acoustic model, the ECHO program commissioned a regional noise Many of the projects being undertaken budget analysis for the months of January through the ECHO program, including the and July 2015 to model average, monthly, underwater listening station and the vessel-generated noise levels for different regional noise model, are developing new sub-regions and different vessel categories. and innovative approaches to Vessel traffic was broken down into general understanding vessel underwater noise. categories including: container ships, oil These technologies and tools could tankers, other merchant vessels, ferries, potentially be applied at other ports tugs, government/research vessels, fishing worldwide. vessels, passenger/cruise ships, recreational The ECHO program serves as an example of boats, whale watching boats and how industry, science, environmental other/unidentified vessels. The output of groups and local community interests can this analysis provides an understanding of work together towards a common goal of how and where each of these categories of reducing the impact of shipping. Through vessels contributes to the underwater early stakeholder engagement, positive soundscape of the region. With this collaboration and informed, science-based information, the ECHO program can identify decision making, the ECHO program could which vessel sectors should be engaged in provide a model for other ports to consider noise reduction efforts and in which when contemplating how to address similar geographical areas, as a means to reduce issues. noise impacts on at-risk whales. More information on the ECHO program can Additionally, the model serves as a powerful be found at: tool to simulate different vessel traffic http://www.portvancouver.com/echo scenarios and evaluate the efficacy of potential mitigation measures. Parameters can be varied within the model to predict

93 Figure 1: The PortListen software provides data on the vessel track, acoustic spectrograph, and calculated broadband source levels, and allows the ECHO program to generate a source level report for provision to the vessel owner. Source: JASCO Applied Sciences PortListen software.

Figure 2: Monthly average sound pressure level (Leq) for January (left) and July (right) 2015 as calculated by the cumulative shipping noise model (BC Albers projection). Source: JASCO Applied Sciences

94 REGIONAL MANAGEMENT OF UNDERWATER NOISE MADE POSSIBLE: AN ACHIEVEMENT OF THE BIAS PROJECT

Thomas Folegot(1), Dominique Clorennec(1), Anna Nikolopoulos(2), Frida Fyhr(2), Mathias Andersson(3) & Peter Sigray(3) (1) Quiet-Oceans, 65 place Nicolas Copernic, 29280 Plouzane, France (2) Aquabiota Water Research, Löjtnantsgatan 25, 115 50 Stockholm, Sweden (3) FOI, Gullfossgatan 6, SE-164 90, Kista, Swedenand the BIAS team

Introduction were used to establish modelled noise maps for the project area, providing the first The EU LIFE+ project Baltic Sea Information results of the Baltic Sea soundscape on a on the Acoustic Soundscape (BIAS) started monthly basis. It deserves to underline that in September 2012 with the aim to support a large number of maps were produced a regional management of underwater noise constituting the base for future in the Baltic Sea, in line with the EU management of noise. To facilitate an roadmap for the Marine Strategy efficient handling of these, and future, Framework Directive (MSFD) and the results GIS-based online tool was created general recognition that a regional handling for visualizing the measured data and the of ambient noise (Descriptor 11) is modelled maps in terms of values and advantageous or even necessary for regions quantities recommended for the such as the Baltic Sea region. implementation of the MSFD descriptor within the context of Good Environmental BIAS dealt exclusively with the MSFD Status (GES). Descriptor Criteria 11.2 Continuous low frequency sound (D11.2) with the aim to Mapping the Baltic Sea implement this indicator, by establishing regionally coherent standards, The production of a noise map relies on a methodologies, and tools that allows for number of activities, ranging from field cross-border handling of acoustic data and surveys, data processing and data analysis, the associated results. The objectives for physical modelling of noise propagation, BIAS were formulated to form a framework inversion or calibration algorithms, etc. The for an efficient joint management of BIAS project has gone through all these underwater sound in the Baltic Sea by stages, including highly demanding data elucidating, and solving, the major control and quality procedures as well as challenges related to the implementation of standardization of the data sets and tools. D11.2, specifically in the Baltic Sea region. Nevertheless, the results are often relevant The BIAS field survey involved all partner also for other marine regions. nations of the project, and a total of 38 acoustic sensors deployed at fixed position As the first implementation of a joint throughout one calendar year as illustrated soundscape monitoring programme across in Figure 1. The field survey resulted in 38 national borders BIAS performed one year series of noise level data, each of them of measurements in 2014 with help of 38 describing the cumulative noise at the acoustic sensors deployed across the Baltic respective measurement position. These Sea by six nations. The measurements, as data were brought into the modelling tool well as the post-processing of the acoustic Quonops© [3] to ground truth the noise data, were subject to standard field maps according to a patented protocol [4] procedures, quality control and signal making use of oceanographic and geological processing routines, all established within parameters which influence the propagation the project [1][2]. The measured acoustic of the underwater sounds[5][6][7][8], as data on continuous low frequency sound well as spatio-temporal data of the maritime

95 activities provided by the Automated Utilizing the noise maps within Identification System (AIS) and the Vessel regional management Movement System (VMS) [9]. The calibration technique used thereafter was Noise maps were produced at a monthly based on the statistical content of the time scale throughout 2014 for the 63 Hz, measured data and the three-dimensional 125 Hz and 2 kHz third octave bands, for a modelled data, similarly to techniques used series of percentile levels (or exceedance in weather now-casting systems. The levels), and for three depth ranges; the full acoustic measurements also served to feed a water-column, depths ranging from the regional model estimating the natural noise surface to 15 m to assess the noise in the caused by wind-generated surface waves surface layer (roughly the euphotic zone in forced by the wind, which were the Baltic Sea), and depths ranging from 30 incorporated into the final noise maps. m to the bottom to assess the deeper layer. An example of the resulting calibrated maps There was a need to establish how to use is shown in Figure 2. The modelling this very large quantity of maps for the approach produced statistical maps purpose of regional noise management, way expressed in terms of percentile levels (Ln), beyond a tool just visualizing the noise defined as the sound pressure level maps and measured data. A dedicated tool exceeded n percent of the time interval was developed to aggregate the information considered. Hence, the series of maps from the maps into different perspectives describe not only the noise levels but also relevant for management. The objectives of the proportion of time subjected to the the tool were to: mapped noise levels. Since there is now a  Simplify the management of continuous large consensus that not only levels are underwater sound in the Baltic Sea important but also the duration of noise, Region, this is a key aspect when it comes to  Serve as a tool for planning, testing and interpreting and using the mapped data for evaluation - a tool for making decisions, the regional management of underwater  Collect and present information from noise. The advantage of percentiles are sound monitoring efforts (BIAS and illustrated in Figure 2 for the month of future ones), including both measured February 2014 with the 75th percentile and modelled data, soundscape (L75) occurring 75% of the  Extract relevant data in user-defined time (or, in total 21 days), the median (L50) areas of specific interest, occurring 50% of the time (or, in total 14  Filter between a large number of days), and the 10th percentile (L10) soundscape maps by selecting particular occurring 10% of the time (or, in total 3 time periods, frequencies, depths, days) of this particular month. It can be percentile levels, etc. of interest, noticed that almost all the time, the major  Produce graphs, maps and plots based on routes across the entire Baltic Sea dominate applied filters. the natural noise. This can be explained by In practice, the tool is able to deliver ad-hoc the permanent high density of the traffic. plots accustomed by the end-user for their Shipping routes in the Bothnian Sea own particular needs, in the range from (northern basin of the monitored area simple to complex questions, e.g “what are between Sweden and Finland) emerge from the sound levels at a certain measurement the natural noise less than half of the time. position?”, “what is the distribution of the This can likely be explained by the most frequent noise in this particular combination of higher ambient noise levels Natura2000 area in June when the harbour in winter times and relatively limited porpoises return?”, or “what proportion of amount of vessels cruising in the area in the essential spawning area for cod is winter times. subject to noise levels comparable at cod communication levels?” The possibilities offered by the tool are here described using a practical case for the

96 Atlantic cod (Gadus morhua), an important  During the two-month period essential species in the Baltic Sea ecosystem. The for cod spawning, 10 to 15% of the area above question may then be rephrased as of this critical habitat has noise levels “what is the spatial coverage (in percent of sufficiently low to ensure that the the area) for where masking of their spawning process is done in good conditions during 15 days per month; acoustic communication may occur for cod 50th percentile (L50)– orange curve. during their spawning period?”. The series of actions for extracting the relevant Conclusion information in the tool would be to: first, select the relevant geographical polygon The BIAS project was directed exclusively delimiting the cod spawning grounds, then towards Continuous low frequency sound chose the 63 Hz third octave band which with the aim to establish a regional reflects cod communication and, finally, implementation plan for this particular select the bottom depth interval which is the MSFD Descriptor Criteria (indicator 11.2). most relevant for cod. Further, an estimate This implied developing regional standards, (a noise threshold level) is needed for the methodologies, and tools enabling cross- reasonable ambient noise level ensuring border handling of acoustic data and the that an individual cod can perceive associated results. But the BIAS project did spawning signals emitted by other fish. This not only result in a plan, it also (and more threshold level was estimated based on the importantly so) resulted in the first practical hearing threshold for the cod, source level implementation of the full chain required to of the cod call and a distance between the monitor and manage this underwater noise fish communicating [10]. In addition, it indicator. turns out that cod spawning is mostly occurring between July and August in the An extensive field survey of ambient noise chosen area. was undertaken covering the full year 2014 by collecting noise measurements at 38 The tool will provide a composite graph as fixed positions. The measurements were illustrated in Figure 3. The graph shows the extrapolated to Baltic Sea full-scale noise proportion of the Bornholm area (more than maps using underwater noise modelling, 8 300 km² total surface) for a series of resulting in a large quantity of soundscape percentile levels, that is, a series of sound information. A regional management tool pressure levels exceeded for a particular was developed, which demonstrated how percentage of time (5, 25, 50, 75, and 95% the information can be aggregated into a of time) from March to September 2014. management friendly concept, sufficiently From this plot we would be able to deduct flexible to provide the end-user with the following: relevant information in their decision- making. A number of regional scenarios  In the sensitive area of Bornholm for cod have been successfully tested and concrete spawning, there are seasonal fluctuations in the noise levels; all curves, decisions managing the effect of noise on the marine fauna can be made using this  The months of June, July and September are the quietest of this period (all innovative and pragmatic approach, curves), although at rare occasions, the bringing the Baltic Sea region one step threshold level seems to be surpassed in closer to true management of Good the entire area independent of the Environmental Status. month; 5th percentile (L05) – blue curve.  During the two-month period essential Acknowledgements for cod spawning (July-August), 50% of the area of this critical habitat has noise This work was supported by the European levels sufficiently low to ensure that the Union LIFE program, The Swedish Agency spawning process is carried out in good for Marine and Water Management, Ministry conditions during a cumulative time of of the Environment of Finland, Estonian seven to eight days per month; 25th Ministry of Defence, Environmental percentile (L25) – red curve, Investment Centre (Estonia), Narodowy Fundusz Ochrony Srodowiska I Gospodarki

97 Wodnej (Poland), and Naturstyrelsen and the SWAN forecast wave model, provided (Denmark) by the Swedish Meteorological and Hydrological Institute. http://www.smhi.se References [6] SMHI, 2014: Open-access data from MESAN weather analysis model, provided by the [1] Betke K., Folegot T., Matuschek R., Pajala J., Swedish Meteorological and Hydrological Persson L., Tegowski J., Tougaard, J., Institute. http://www.smhi.se Wahlberg M. (2015). BIAS Standards for Signal Processing. Aims, Processes and [7] EMODnet, 2012: Seabed substrate data Recommendations. Amended version. 2015. (version 28.6.2012) made available by the EMODnet (European Marine Observation and Editors: Verfus U.K., Sigray P. Data Network) Geology project, funded by [2] Verfuß, U.K., Andersson, M., Folegot, T., the European Commission Directorate Laanearu, J., Matuschek, R., Pajala, J., Sigray, General for Maritime Affairs and Fisheries. P., Tegowski, J., Tougaard, J. BIAS Standards http://www.emodnet-geology.eu for noise measurements. Background [8] BSHC, 2013: Baltic Sea Bathymetry Database information, Guidelines and Quality version 0.9.3. Downloaded from the Baltic Assurance. Amended version. 2015. Sea Hydrographic Commission [3] Folegot, Thomas, Ship traffic noise http://data.bshc.pro/ in January 2016. distribution in the : an [9] HELCOM, 2014: Automatic Identification exemplary case for monitoring global ocean noise, Conference on the effect of noise on System (AIS) shipping traffic data from the HELCOM database hosted by the Danish aquatic life. Cork, Ireland: Springer, 2010. Maritime Authority (DMA) and administered [4] Folegot, T.. Method for monitoring, predicting by the HELCOM AIS Expert Working Group. and reducing the level of acoustic energy of a http://www.helcom.fi plurality of sources in an aquatic environment and method for monitoring, [10] Andersson, M.H., Persson, L.K.G., Lucke, K., predicting, and reducing the risk of noise Folegot, T., Baudin, E., André, M. (2015). Criteria for bioacoustic sensitivity in annoyance for marine species. European maritime areas. Scientific report D.4.5, Union Patent EP2488839. 10 October 2009. AQUO- FP7 - Collaborative Project n°314227, [5] SMHI, 2014: Open-access data from the 25 pp. HIROMB BS01 oceanographic forecast model

Figure 1: Noise monitoring strategy applied during the BIAS project in 2014. Dots represent the sensor positions overlaying the major shipping routes in the Baltic Sea.

98 Figure 2: Three statistical maps of noise in the 125Hz third octave for February 2014. L75 is the 75th percentile – or 75% of the time in February, L50 is the median – or 50% of the time in February, and L10 is the 10th percentile – or 10% of the time in February

Figure 3: Temporal variations of spatial coverage of the noise levels above a user- defined threshold level. The graph is extracted from the series of noise maps as one of three possible graphical options in the BIAS soundscape planning tool.

99

EMBEDDED PROCESSING TECHNOLOGIES FOR UNDERWATER NOISE MONITORING: EXPERIENCE FROM THE GERMAN OFFSHORE WINDFARMS

Luc Simon(1), Caroline Magnier(1) & Federica Pace(2) (1) RTsys SAS, France / (2) Baker Consultants, UK

Internationally, underwater noise impacts operators a tool with key information on marine life related to offshore wind feedback and intuitive display so that they farms has been a growing issue. Of which, in will be able to master themselves general European shallow waters, the main understanding in underwater noise consideration states around installation of monitoring. monopiles generating very high-level of impulse noises. After detailing te challenges, we will be present successful experiences and In Europe, the Technical Subgroup on feedbacks from German Wind Farms where Underwater Noise (TSG noise) provided a unique innovative solution for real-time guidance for member states on meeting the pile driving noise monitoring has been requirements of the Marine Strategy implemented and show how such tool can Framework Directive (MSFD) with regards not only meet the regulations expectations to underwater noise, of which measurement but finally also be used as a decisional time- of sounds such as pile-driving, and its saving tool for operators. potential impact on marine life. Underwater noise embedded As an example in Europe, leading the way in processing challenge the area of noise regulations, Germany, via its Federal Maritime and Hydrographic Gathering exploitable calibrated noise Agency, BSH, defined a threshold limitation data of Sound Exposure Level (SEL) at 750 meters from the monopiles for offshore With regulations where we can encounter wind farms constructions. threshold limitations or a +/-1dB difference in measurement and calculation of the Other regulations are intending to propose a underwater noise level can modify a cetacean protected zone (NOAA) where the regulation decision and paralyze expectations of the passive acoustic devices construction operation. It is then crucial for are to detect, classify, identify and ideally measurement device to be able to provide track the presence of a mammal in a qualitative and adapted raw data that will variable surface area. be used for interpretation. Therefore, industrials helped by passive Acquisition of high quality data offers a acoustic surveyors are requested to provide number of major challenges commonly seen. in a short response time a detailed and These include operation across wide accurate reporting following standards and dynamic ranges and wide bandwidths (a guidelines, this is where it is required to few Hz – many hundreds of kHz) with low provide a real-time solution to answer self-noise and great dynamic range. regulations. Nevertheless, gathering high quality of data, The first challenge relies in gathering autonomous sound recording can represent qualitative underwater noise data and a considerable amount of data (.wav) in a provide embedded processing capable of few day time, representing Tera-Bytes of high performance while achieving low data per device. power consumption. The second challenge is to rely both on regulation and standardization expectations and to provide

101 Real time challenge increasing power consumption nor requiring external computing unit; which is In real time, different limitations appear; specifically well suited for remote such as power consumption – especially if applications in harsh marine environments an external PC unit is required, or at the where reasonable sized and robust contrary self-limitation of embedded equipment are required. The embedding processors or DSP such as the memory and processing methodology used on the RB- computing time integration. SDA14 buoy developed to calculate noise Moreover, the more information we need to levels (SEL, Sound Exposure Levels, SPL, extract from processing, the more filtering is instantaneous pressure levels of average required; in that case, filtering data is a levels calculated for each strokes) is time-consuming action: the computing time designed to be fully approved by authorities highly increases as the length of data and therefore based on international increases which present the risk of losing standards on noise level measurement and real-time capabilities. calculation. Morevoer work has been achieved in order to offer solutions allowing Real-time noise monitoring regular on-the-field calibration procedures. Real-time (or online) noise monitoring has Real-time noise monitoring benefits: many advantages in helping offshore wind examples farm developers to meet both EU- and country-level underwater noise requirements, The integration of autonomous recorders including increasingly shorter deadlines for with a live monitoring buoy that permits reporting schedules. processing of the required information and transmission of the data to vessels nearby The main advantage of using real-time has many benefits. monitoring is that the received feedback can be used as a mitigation tool, giving the One of the key benefits of real-time noise operator the opportunity to adjust the piling monitoring is the ability to effectively use strategy as necessary, and can aid the quick the received feedback as a mitigation tool. identification of equipment faults, both of This means that the operator on board a which can achieve significant cost savings. piling vessel can view the noise levels that Real-time monitoring buoys can also are being recorded a certain distance away monitor the surrounding area for the in real-time and adjust the piling strategy as presence or absence of target species, such necessary. as harbour porpoises, which some countries For instance, the operator can decrease the require. piling energy to remain below certain noise Real-time monitoring involves deploying a levels, or increase the energy to minimise small- to medium-sized buoy connected to a the time needed to drive the pile into the hydrophone (an underwater sensor that substrate if current noise levels are low. detects changes in pressure and translates Optimising the piling strategy with live them into an electrical signal). The buoy feedback from the noise measurements in both records and stores all the acquired this way can achieve significant cost- data as well as processing the incoming data savings. and transmitting the required noise Finally, real-time noise monitoring buoys levels to a receiver unit. This unit can be can be used to monitor the surrounding installed on the piling vessel or any other area for the presence or absence of target service vessel. The processed data that is species, such as harbour porpoises, which transmitted can be customised to suit are a protected species throughout the EU. specific project needs. This is beneficial because, whilst some EU Embedded processing provide significant governments have imposed strict advantages as it gathers key information thresholds on noise emissions, others together with raw data storage without instead require monitoring to be conducted

102 to determine whether marine mammals are References present within a certain area during operations. If they are, then mitigation Technical Memorandum: Technical Guidance for measures must be used to minimise Assessing the Effects of Anthropogenic Sound disturbance of marine mammals. on Marine Mammal Hearing - NOAA European Marine Strategy Framework Directive Good Environmental Status (MSFD-GES) Report of the Technical Subgroup on Underwater Noise and other forms of energy - EU Offshore wind farms Measuring instruction for underwater sound monitoring – BSH, Germany Standard for measurement and monitoring of underwater noise Part I – TNO, Netherlands

Screenshot of real-time pile-driving noise monitoring interface – Rtsys France

Real-time underwater noise monitoring buoy to be deployed in German Offshore WindFarm – picture credits Baker Consultants

103

PROGRESS IN ADDRESSING MAN-MADE NOISE IN THE MEDITERRANEAN SEA: ASSESSMENT AND REGULATION AT A BASIN-WIDE SCALE

Alessio Maglio(1), Gianni Pavan(2), Manuel Castellote(3), Silvia Frey(4) & Maylis Salivas(5) (1) SINAY, 117 Cours Caffarelli, 14000 Caen, France (2) CIBRA, D.S.T.A., Università di Pavia, Via Taramelli 24 – 27100 Pavia, Italy (3) National Marine Mammal Laboratory, Alaska Fisheries Science Center/NOAA, 7600 Point Way N.E. F/AKC3, Seattle, WA 98115-6349 (4) OceanCare, Gerbestrasse 6, P.O. Box 372, CH- 8820 Wädenswil, Switzerland (5) ACCOBAMS Permanent Secretariat, Jardin de l’UNESCO, Terrasses de Fontvieille, 98000 Monaco

Introduction underwater noise inputs into the Agreement area. Such efforts were undertaken with the The Mediterranean region presents a lack of aim to achieve the global objectives of knowledge, monitoring tools and regulation ACCOBAMS as well as to support the work for assessing the use of noise sources and of the Convention for the Protection of the their impact on the marine environment. Marine Environment and the Coastal Region Within the area, several studies already of the Mediterranean (Barcelona showed evidence of the impact entailed by Convention). The two bodies share indeed anthropogenic underwater noise to common areas (the Mediterranean Sea) and sensitive species like cetaceans [1]–[4], goals such as implementing measures while some risk studies were carried out to against pollution and ensuring the identify habitats where the use of noise conservation of endangered species. sources could cause harm to cetaceans, especially to beaked whales [5], [6]. On the The ACCOBAMS Agreement has addressed other hand, little efforts were made to the impact of underwater noise on assess levels and effects of maritime human cetaceans since 2004 primarily through activities. Recent projects providing first Resolutions 2.16, 3.10, 4.17, 5.13 [9]–[12], data and results at a regional scale are the and by providing expertise to the Barcelona MEDTRENDS and MEDGIS-MAR project [7], Convention concerning the implementation [8]. However, these initiatives do not of an ecosystem based regulation in the specifically address the underwater noise basin. issue. In this paper we present the progress in In terms of regulation, the role of Regional addressing man-made noise achieved thus Seas Conventions existing in the far in the framework of two initiatives: the Mediterranean is of primary importance to development of a monitoring strategy for promote and spread the adoption of rules underwater noise in the Mediterranean Sea; concerning the emissions of underwater and the assessment of the spatial and noise, as they include Contracting Parties temporal distribution of noise-producing which are not Member States of the human activities. European Union (EU) and thus are not bound to European directives or regulations Initiatives for regulating and (such as the Marine Strategy Framework assessing underwater noise Directive, MSFD). emissions In this context, recent efforts have been Ecosystem Approach – Ecological undertaken within the Agreement on the Objective 11 Conservation of Cetaceans in the Black Sea, In 2014 and 2015, ACCOBAMS and the the Mediterranean Sea and the contiguous Barcelona Convention cooperated in order Atlantic Area (ACCOBAMS) aiming at to develop a preliminary strategy applying understanding, assessing and regulating to the whole Mediterranean Sea for

105 assessing and monitoring underwater noise. marine animals”. In the above definition, This strategy was developed in the proportion of days is to be interpreted as framework of the Ecosystem Approach the number of days over a calendar year; (EcAp) project. EcAp is an initiative of the geographical distribution is defined as the Barcelona Convention started in 2008 and number of grid cells over a 20x20 km grid having the same overall objectives of the covering the whole Mediterranean basin; MSFD, including the achievement and/or impulsive sounds are to be interpreted as maintenance of the Good Environmental source levels of anthropogenic noise Status (GES) of the marine environment sources; impact is defined as severe and/or [13]. EcAp and the MSFD share also a sustained and/or long-term avoidance of an similar structure, whereby 11 Ecological area, and/or disruption of acoustic Objectives (EOs) of EcAp correspond to 11 behaviour, i.e. stop calling and/or stop Descriptors of the MSFD, the eleventh being clicking. Finally, the EO11 Guidance defines in both cases “Energy including underwater what impulsive noise sources are to be noise”. For these reasons and given that taken into account for monitoring and some countries are at the same time assessment: it is recommended to consider Member States of the EU and Contracting all human activities using low frequency Parties to ACCOBAMS and the Barcelona noise sources, regardless of their source Convention, the ACCOBAMS strategy was level, thus accounting for fin whale developed as to be consistent with the sensitivity over very long ranges. guidance from the Task Group on Noise of Furthermore, the EO11 Guidance the European Commission [14]–[16]. It was recommends addressing also human approved by different technical meetings of activities using mid frequency noise the Barcelona Convention in 2015, and provided their source levels exceeds a fixed finally adopted through Decision IG.22/7 at threshold. Thresholds for mid frequency 19th Ordinary Meeting of the Contracting noise sources were set in order to account Parties in 2016 [17] for Cuvier’s beaked whale sensitivity to mid frequency sounds. So, in order to define GES In practice, the strategy is a technical related to indicator 26, it is recommended guidance (EO11 Guidance), outlining the to establish a spatial threshold (i.e. a indicators related to EO11, and providing number of cells over a grid) and a time information for stakeholders to implement threshold (i.e. a number of days over a the recommended monitoring and calendar year). Exceeding either of such assessment programmes. Two separate thresholds in a given year means that GES is indicators are proposed: Common Indicator not attained for that year. 26 addresses space-time distribution of impulsive noise sources, while Common Common Indicator 27 is defined as “Levels Indicator 27 addresses levels of continuous of continuous low frequency sound with the noise through the use of measurements and use of models as appropriate”. The EO11 models as appropriate. The methodology Guidance proposes to focus on specific outlined in the strategy proposes some frequency bands, i.e. the third-octave bands adaptations for the Mediterranean case centred at 20, 63, 125, 250, 500 and 2000 compared to Descriptor 11 of the MSFD Hz. Frequency bands were selected where (D11). Particularly, both indicators are more shipping noise is likely to be dominant closely related to the acoustic biology of key compared to other sources according to marine mammal species of the Mediterranean data (63, 125, 250 and 500 Mediterranean which are known to be Hz), but also where noise potentially masks sensitive to noise, i.e. the fin whale, the fin whale calls and sperm whale clicks (20 sperm whale and the Cuvier’s beaked whale. Hz and 2000 Hz, respectively). Two metrics are recommended for monitoring: the Common Indicator 26 is defined as annual arithmetic mean Sound Pressure “Proportion of days and geographical Level (SPL), expressed in dB re 1µPa (rms); distribution where loud, low and mid- and the annual 33.3% Exceedance Level (or frequency impulsive sounds exceed levels L33.3), meaning the noise level exceeded that are likely to entail significant impact on

106 33.3% of a calendar year. L33.3 is aimed at this is limited to the year. Available data for accounting for possible increase in ambient seismic exploration allowed for calculating noise levels due to recreational craft in the surface annually bestowed to this summer. In fact, it is assumed that activity in the 2005-2015 period. The recreational craft can cause significant highest value was attained in 2013 with increase in ambient noise levels during the seismic survey areas covering around summer period, i.e. June to September, 675 000 km², representing 27% of the which represents a third (= 33.3%) of a surface of the Mediterranean (2.5 M km²). year. So, in order to define GES related to On the opposite, 2005 yielded the lowest indicator 27, it is recommended to establish value with around 67 000 km² used (3.8% a conservative noise threshold. If the annual of the Mediterranean surface). An increasing arithmetic mean SPL is above the noise trend over the study period is highlighted. threshold, GES is not met that year for that Furthermore, the position of each category region while if the mean is below, the L33.3 is of noise-producing human activities was inspected to figure out if during summer the mapped. Subsequently, summary GIS maps threshold was exceeded. If so, GES is not were created using a grid resolution of met again. 40x40 km in order to investigate the accumulation of noise-producing human Identifying hotspots of noise-producing activities across the study area and to point human activities out overlaps with important cetacean A first basin-wide assessment of the spatial habitats. Areas exposed to multiple noise- and temporal distribution of noise- producing human activities (noise hotspots) producing human activities in the were located in the Italian part of the Mediterranean Sea was carried out in 2015 Adriatic Sea, the Strait of Sicily, the French [18]. The overall objective of this work was Eastern coastal waters, the North-eastern to gather an overview of the occurrence of part of Corsica, the higher Ionian Sea, and the activities identified as being of highest the coast of Campania. These areas risk for marine wildlife and particularly for accumulated all categories of noise- cetaceans. It is worth noting that this work producing activities considered in this meant providing data and information of study: harbour activities, commercial and interest also for the EO11 and D11 in the scientific seismic surveys, oil and gas Mediterranean area, although the technical drilling activities, wind farms projects, guidance related thereto was not followed military exercises. Finally, when strictly as the necessary data are currently overlapping cetacean habitats with not available in the Mediterranean region. identified noise hotspots, potential conflict Main tasks planned for this study included: areas were shown for the Ligurian Sea, the (i) inventorying noise-producing human Strait of Sicily and the Northern part of the activities and (ii) mapping areas where such Hellenic Trench. activities were carried out. Although not exhaustive, this study put together a large Discussion and Conclusion amount of data, particularly on activities Initiatives described in this paper outline using impulsive noise sources, for the the work supported by ACCOBAMS in period 2005 to 2015 and for the next future, cooperation with the Barcelona Convention i.e. activities scheduled until 2020. in order to develop a regulation framework Main results deal with human activities for underwater noise at the Mediterranean during which impulsive noise sources are scale and to assess the current status of the usually employed. Data were recorded on spatial and temporal distribution of noise- the position of 1446 harbours, 228 drilling producing human activities in this area. platforms for hydrocarbon exploitation, 52 Both initiatives are linked to each other as wind farm projects, 830 seismic exploration well as to other important processes like the areas, and a number of military areas; MSFD, and they appear of particular whenever possible, the period of occurrence importance as they apply beyond the of activities was recorded, but most times boundaries of the EU. The overview on the

107 noise hotspots represents a first discussion [6] A. Cañadas, A. B-Nagy, G. Bearzi, C. Cotté, C. ground concerning the need for Fortuna, A. Gannier, S. Laran, G. Lauriano et conservation measures and al., “Accobams Collaborative Effort To Map th monitoring/assessment programmes, and High-Use Areas By Beaked,” in 8 Meeting of can feed the discussions concerning GES the ACCOBAMS Scientifc Committee, 2012, p. 23. definition relative to underwater noise, which is relevant for both the EcAp [7] C. Piante and D. Ody, “Blue Growth in the initiative and the MSFD process. Mediterranean Sea: the Challenge of Good Environmental Status,” p. 192, 2015. Difficulties identified during the [8] REMPEC, “MEDGIS-MAR.” [Online]. Available: implementation of such initiatives are the http://medgismar.rempec.org/ different capacity in implementing noise [9] ACCOBAMS, “Resolution 2.16 Assessment regulation across Mediterranean countries and impact assessment of man-made noise.” and the poor quality of many of the available [10] ACCOBAMS, “Resolution 3.10 Guidelines to data on the spatial and temporal address the impact of anthropogenic noise.” distribution of noise-producing human 2007. activities, particularly for Southern and [11] ACCOBAMS, “Resolution 4.17 Guidelines to Eastern Mediterranean countries. Next steps address the impact of anthropogenic noise on will need to cope with these difficulties to cetaceans in the ACCOBAMS area,” 2010. ensure an acceptable balance between [12] ACCOBAMS, “Resolution 5.15 addressing marine conservation and human the impact of anthopogenic noise.” 2013. development at sea. [13] UNEP/MAP, “Report of the 15th Ordinary Meeting of the contracting Parties to the References Convention for the Protection of the Marine [1] J. F. Borsani, C. W. Clark, B. Nani, and M. Environment and the coastal region of the Scarpiniti, “FIN WHALES AVOID LOUD mediterranean and its Protocols,” Almeria, RHYTHMIC LOW- FREQUENCY SOUNDS IN 2008. THE LIGURIAN SEA,” Bioacoustics - Int. J. [14] R. Dekeling, M. Tasker, A. Van der Graaf, M. Anim. Sound its Rec., vol. 17, pp. 151–193, Ainslie, M. Andersson, M. Andre, J. Borsani et 2008. al., “Monitoring Guidance for Underwater [2] N. Aguilar de Soto, M. Johnson, P. T. Madsen, Noise in European Seas, Part II: Montitoring P. L. Tyack, A. Bocconcelli, and F. J. Borsani, Guidance Specifications,” 2014. “Does Intense Ship Noise Disrupt Foraging in [15] R. Dekeling, M. Tasker, A. Van der Graaf, M. Deep-Diving Cuvier’S Beaked Whales Ainslie, M. Andersson, M. Andre, J. Borsani, et (Ziphius Cavirostris)?,” Mar. Mammal Sci., al., “Monitoring guidance for underwater vol. 22, no. 3, pp. 690–699, Jul. 2006. noise in European Seas, part III: Background [3] M. Castellote, C. W. Clark, and M. O. Lammers, information and annexes,” 2014. “Acoustic and behavioural changes by fin [16] R. Dekeling, M. Tasker, A. Van der Graaf, M. whales (Balaenoptera physalus) in response Ainslie, M. Andersson, M. Andre, J. Borsani et to shipping and airgun noise,” Biol. Conserv., al., “Monitoring Guidance for Underwater vol. 147, no. 1, pp. 115–122, Mar. 2012. Noise in European Seas. Part I: Executive [4] A. Frantzis, “Does acoustic testing strand Summary. JRC Scientific and Policy Report whales?,” Nature, vol. 392, no. 6671, p. 29, EUR 26557 EN” 2014. Mar. 1998. [17] UNEP/MAP, “Integrated Monitoring and th [5] A. Azzellino, C. Lanfredi, A. D’Amico, G. Pavan, Assessment Guidance,” in 19 Ordinary M. Podestà, and J. Haun, “Risk mapping for Meeting of the Contracting Parties to the sensitive species to underwater Convention for the Protection of the Marine anthropogenic sound emissions: model Environment and the Coastal Region of the development and validation in two Mediterranean and its Protocols, 2016, no. 9– Mediterranean areas.,” Mar. Pollut. Bull., vol. 12 February, p. 282. 63, no. 1–4, pp. 56–70, Jan. 2011. [18] A. Maglio, G. Pavan, M. Castellote, and S. Frey, “Overview of the Noise Hotspots in the ACCOBAMS Area, Part I - Mediterranean Sea,” 2016.

108 Indicator Operational Parameter Description State/Pressure GES assessment Guidelines N° objective description Proportion of days and GES is not geographical Number of days achieved or distribution where loud, over a year and maintained if Common low and mid-frequency number of cells either the Indicator impulsive sounds over a grid in temporal or 26 exceed levels that are which activities spatial likely to entail using loud source Energy inputs thresholds are Adapted from significant impact on levels occur into the marine exceeded the Monitoring marine animals environment, Guidance for Arithmetic mean especially noise Pressure Underwater SPL over a year from human Noise in (dB re 1µPa rms) GES is not activities, is European Seas and achieved or Levels of continuous low minimized [14]–[16] Common L , i.e. 33% maintained if the frequency sound with 33.3 Indicator exceedance level L index, the use of models as 33.3 27 (dB re 1µPa rms) calculated over a appropriate in the 1/3 octave year, is above bands centred at: the threshold 20, 63, 125, 250, 500 and 2000 Hz

Table 1: Synthesis of the technical guidance for the Ecological Objective 11 of the EcAp initiative

Figure 1: Noise-cetacean interaction hotspots: Accumulation of noise-producing human activities (4 categories considered: harbour activities; offshore works including Oil & Gas drilling sites and windfarm projects; seismic surveys, military exercises) and overlaps with important cetacean habitats

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Appendix

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PRESENTATION OF THE PROJECT

This position paper results from a project the diffusion of communication carried out at the Observatory for technologies, health, innovation, energy and Responsible Innovation. The Observatory sustainable development. These activities for Responsible Innovation is an are organized around four main topics: independent international think tank  Transformations of innovating firms created to reflect on and discuss new concepts, measures and methods for  Theories and models of design encouraging responsible innovation. The  Regulations of innovation Observatory is based in Mines ParisTech  Uses, participation and democratization and is part of i3, the Interdisciplinary of innovation Institute of Innovation (CNRS UMR 9217). For more information: This Institute was founded by the CNRS, in  http://www.i-3.fr/ collaboration with Mines ParisTech, Ecole  http://www.debatinginnovation.org Polytechnique and Telecom Paris. Organization of the project The Observatory for Responsible Innovation and i3 The project started at a time when it was possible to take advantage of the work of This think tank views innovation as a two European projects focusing on shipping process that is both full of promises and noise (SONIC, AQUO) and of the oil & gas fraught with dangers, with negative industry initiative on sound measure, but externalities. Its philosophy is rooted in the also at a point when it had become crucial to question of technical democracy as think about implementing innovative understood by Michel Callon. Its main goal solutions. is to organize debate around innovation, to animate a political discussion, and attract A working group was organized and media attention to it. To do so, the coordinated by Héloïse Berkowitz and Observatory mostly provides human Hervé Dumez, and involved: Eric Baudin resources. from BureauVeritas, Christian Audoly and Céline Rousset from DCNS; Aldo Napoli, The Interdisciplinary Institute of Innovation researcher in risk modeling at Mines (i3, CNRS UMR 9217), founded in 2015, ParisTech, and Fabian Muniesa, chairman of brings together: the Observatory for Responsible Innovation.  the Mines ParisTech economics, The objective of the project was to explore management and sociology research with scientists, industry representatives, teams (CERNA, CGS and CSI), and national and European public officers  those of the Department of Economics the best way to develop solutions. The and Social Science (DSES) at Télécom ParisTech, position paper you are reading was  and the Management Research Center prepared thanks to three one-day (CRG) at Ecole Polytechnique, workshops on the following topics: and thus comprises more than 200 people,  Noise measurement: two ISO groups including 60 permanent academic worked on this topic. The workshop researchers. highlighted the problems and stakes linked to the definition of an efficient It pursues high-level research, combining standardized measurement instrument; academic excellence and relevance for the  Noise impact on marine life: This end users. Through its teaching and workshop tried to delineate the state-of- research activities, i3 takes an active part in the-art about the impacts of underwater addressing main contemporary challenges:

113 noise on marine (mammals, fish, underwater noise footprint of ships. This invertebrates, etc.); workshop sought to summarize and  Innovative solutions and management present the most innovative solutions devices: industrial actors are developing being implemented in different sectors. many innovations to reduce the

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122 LEXICON/GLOSSARY

Anthropophony: chorus of sounds Sound pressure: local variation in pressure produced by humans, whether coherent caused by a sound wave. such as music or dialogue, or incoherent such as those generated by Sound pressure level (SPL): acoustic electromechanics. pressure level is a logarithmic measure of the effective pressure of a sound relative to Biophony: chorus of sound from living a reference value. organisms. Soundscape: set of elements in the acoustic Geophony: chorus of natural sounds such environment that life beings can perceive. as noise from the rain, waves, seisms, or Human soundscape vary from fish even storms for instance. soundscape. Soundscape is distinct from acoustic environment that covers the whole Good environmental status: range of sound sources, from natural Masking: noise pollution interferes with an biophony to geophony and anthropophony. animal’s use of sounds to detect other Underwater acoustic pollution: anthropic animals, to interpret, to hunt etc. introduction of energy in the form of Particle Motion: sound is actually vibratory acoustic emission that negatively affects energy that propagates through oscillating marine fauna’s behaviors, physiologies or particles that then move close particles population. which in turn move particles next to them. Particles in a medium such as water do not actually travel; they only transmit oscillation, which is called particle motion.

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