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A noisy spring: The impact of globally rising underwater sound levels on fish

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Abstract

The underwater environment is filled with biotic and abiotic sounds, many of which can be important for the survival and reproduction of fish. Over the last century, human activities in and near the water have increasingly added artificial sounds to this environment. Very loud sounds of relatively short exposure, such as those produced during pile driving, can harm nearby fish. However, more moderate underwater noises of longer duration, such as those produced by vessels, could potentially impact much larger areas, and involve much larger numbers of fish. Here we call attention to the urgent need to study the role of sound in the lives of fish and to develop a better understanding of the ecological impact of anthropogenic noise.

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... The presence of noisy human activities may damage, deter, distract, interfere, or just be audible to aquatic animals (Ladich, 2008;Slabbekoorn et al., 2010;Hawkins et al., 2015;Erbe et al., 2016;Cox et al., 2018;Southall et al., 2019;Popper and Hawkins, 2019). Behavioural and physiological properties can be considered to be the most important as they potentially yield effects at population and, possibly, ecosystem level (Kunc et al., 2016;Soudijn et al., 2020). ...
... Behavioural and physiological properties can be considered to be the most important as they potentially yield effects at population and, possibly, ecosystem level (Kunc et al., 2016;Soudijn et al., 2020). They have potential impact at moderate levels but over large distances from the noisy human activities, reaching many species and individuals (Slabbekoorn et al., 2010;Popper and Hawkins, 2019). Masking occurs when, for example, sounds from human activities overlap in time, frequency, and direction with biologically relevant sounds (Brumm and Slabbekoorn, 2005;Erbe et al., 2016;Dooling and Leek, 2018). ...
... There are many studies showing the behavioural or physiological effects from sound exposure on fishes (Slabbekoorn et al., 2010;Cox et al., 2018;Popper and Hawkins, 2019), but assessing impact on free-ranging individuals from an anthropogenic source, such as a seismic survey, remains difficult and rarely performed (Pearson et al., 1992;Hassel et al., 2004;Fewtrell and McCauley, 2012;Bruce et al., 2018;Carroll et al., 2017;Morris et al., 2018;Morris et al., 2020;Slabbekoorn et al., 2019;Kok et al., 2021). The sounds from anthropogenic activities may reach fish by direct propagation through the water column or indirect propagation through the substrate (Hazelwood, 2012;Roberts and Elliot, 2017;Popper and Hawkins, 2019). ...
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The aquatic world of animals is an acoustic world as sound is the most prominent sensory capacity to extract information about the environment for many aquatic species. Fish can hear particle motion, and a swim bladder potentially adds the additional capacity to sense sound pressure. Combining these capacities allows them to sense direction, distance, spectral content, and detailed temporal patterns. Both sound pressure and particle motion were recorded in a shallow part of the North Sea before and during exposure to a full-scale airgun array from an experimental seismic survey. Distinct amplitude fluctuations and directional patterns in the ambient noise were found to be fluctuating in phase with the tidal cycles and coming from distinct directions. It was speculated that the patterns may be determined by distant sources associated with large rivers and nearby beaches. Sounds of the experimental seismic survey were above the ambient conditions for particle acceleration up to 10 km from the source, at least as detectable for the measurement device, and up to 31 km for the sound pressure. These results and discussion provide a fresh perspective on the auditory world of fishes and a shift in the understanding about potential ranges over which they may have access to biologically relevant cues and be masked by anthropogenic noise.
... Sound is a key sensory cue used by fishes to perceive their environment (Popper et al., 2014;Slabbekoorn et al., 2010). They use sound for communication, navigation, orientation, mating, foraging, and predator avoidance (Fay & Popper, 2000;Popper, 2003;Slabbekoorn et al., 2010). ...
... Sound is a key sensory cue used by fishes to perceive their environment (Popper et al., 2014;Slabbekoorn et al., 2010). They use sound for communication, navigation, orientation, mating, foraging, and predator avoidance (Fay & Popper, 2000;Popper, 2003;Slabbekoorn et al., 2010). All fish species studied to date can detect sound (Slabbekoorn et al. 2010;Popper & Fay, 2011) typically in the range of 30 to 5,000 Hz, overlapping with relevant sources of shipping noise (Figure 15). ...
... They use sound for communication, navigation, orientation, mating, foraging, and predator avoidance (Fay & Popper, 2000;Popper, 2003;Slabbekoorn et al., 2010). All fish species studied to date can detect sound (Slabbekoorn et al. 2010;Popper & Fay, 2011) typically in the range of 30 to 5,000 Hz, overlapping with relevant sources of shipping noise (Figure 15). ...
... Sound is detected as sound pressure (waves) and particle motion (Urick, 1983), both of which are important to marine species (Slabbekoorn et al., 2010;Hawkins and Popper, 2016;Popper and Hawkins, 2018). Highly varied physiology allows marine animals to produce and hear a range of sounds which are part of the natural "soundscape" in the ocean (Slabbekoorn et al., 2010;Popper and Hawkins, 2018). ...
... Sound is detected as sound pressure (waves) and particle motion (Urick, 1983), both of which are important to marine species (Slabbekoorn et al., 2010;Hawkins and Popper, 2016;Popper and Hawkins, 2018). Highly varied physiology allows marine animals to produce and hear a range of sounds which are part of the natural "soundscape" in the ocean (Slabbekoorn et al., 2010;Popper and Hawkins, 2018). Marine mammals, fish and invertebrates produce and hear a variety of sounds which may allow them to communicate (e.g., socially, in courting, during breeding, as warnings, in defense, in competition and mating rituals), find prey, avoid predators, as settlement cues and to navigate (Deecke et al., 2002;Gannon et al., 2005;Slabbekoorn et al., 2010;Curé et al., 2013;Janik and Sayigh, 2013;Matthews et al., 2017;Popper and Hawkins, 2018). ...
... Highly varied physiology allows marine animals to produce and hear a range of sounds which are part of the natural "soundscape" in the ocean (Slabbekoorn et al., 2010;Popper and Hawkins, 2018). Marine mammals, fish and invertebrates produce and hear a variety of sounds which may allow them to communicate (e.g., socially, in courting, during breeding, as warnings, in defense, in competition and mating rituals), find prey, avoid predators, as settlement cues and to navigate (Deecke et al., 2002;Gannon et al., 2005;Slabbekoorn et al., 2010;Curé et al., 2013;Janik and Sayigh, 2013;Matthews et al., 2017;Popper and Hawkins, 2018). Invertebrate hearing is less well understood and receives less attention but, species may be sensitive to particle motion and vibrational sound (Nedelec et al., 2016;Popper and Hawkins, 2018). ...
Chapter
Understanding the complexity of environmental impacts of tidal and wave energy converters (TECs, WECs) still presents a major challenge to the expansion of the marine renewable energy (MRE) industry, particularly for new developments. Using the stressor-receptor framework, we broadly introduce the main environmental effects and potential impacts that are considered for TEC and WEC developments. We first provide an overview of the legislation that governs the need to consider the environmental impacts, and the diverse approaches taken to assess them. We then outline potential effects of relevance to the abiotic and biotic environment in the vicinity of TECs and WECs. These include receptor responses to changes in hydrodynamics and sediments, habitat modification, animal collision risk with dynamic parts of devices, and energy emissions including receptor responses to noise and electromagnetic fields associated with installations. We provide an overview of how changes may directly and indirectly influence components of the ecosystem (e.g., habitats, species, processes). In doing so, we highlight the tools presently in use to monitor or research these effects, identify knowledge gaps, as well as future research needs and strategies. A better understanding of the effects of diverse installations will ultimately support the expansion of the MRE industry. Furthermore, this knowledge will facilitate assessments of cumulative effects and inform marine spatial planning, supporting the implementation and management of sustainable developments in our ocean.
... Vessel noise could pose a serious threat to both individual animals and entire populations (Weilgart, 2007b;Clark et al., 2009;Slabbekoorn et al., 2010). Predicting future trends of vessel noise pollution and identifying efficient mitigation measures could help to reduce noise pollution impacts on fish in future years. ...
... Anthropogenic threats need to be managed effectively to prevent further decline of marine species. Research on noise in the marine ecosystem has been recognised as a means of improving environmental management Popper andHastings, 2009a, 2009b;Slabbekoorn et al., 2010). However, more research is still needed to provide improved knowledge of marine noise pollution impacts, and to develop assessment metrics capable of more accurately measuring the impact of anthropogenic noise on marine life. ...
... Although vessel noise is not as intense as other anthropogenic noise sources it is constant over time, can be considered both continuous (as background noise) and intermittent (when passing in close proximity), and is widespread throughout the world's oceans (Celi et al., 2016;Radford et al., 2016b). Vessel noise could pose a serious hazard not only to individual animals, but also to entire populations (Weilgart, 2007b;Clark et al., 2009;Slabbekoorn et al., 2010). Although noise impact research and knowledge has increased greatly over recent decades, the overall picture remains incomplete, especially in relation to population level consequences of noise exposure (McGregor et al., 2013). ...
Thesis
The effects of noise on aquatic life is a topic of growing international concern. Underwater noise can impact both the physiology and behaviour of fish species on a wide-ranging scale, from minor changes and adaptations to major injury and death. Future mitigation of anthropogenic noise in the ocean is dependent on greater awareness of the effects of noise, the amount of risk, and degree of harm, likely to affect fish populations. Currently, there is a lack of incentive for mitigation measures to be put in place. Knowledge and evidence of the impacts of anthropogenic noise on fish is rapidly increasing (Figure 1.2) but with over 32,000 species of fish of differing conservation and commercial importance, it is extremely difficult to decide where to focus research for maximum benefit (Hawkins et al., 2015). Predictions and assumptions about potential impacts lack accuracy as variations in experimental equipment and techniques, lack of agreed standards, different algorithms for analysis, ambiguous and interchangeable terminology, and different quantities, units and metrics, all lead to incongruities (ISVR Consulting, 2004; Barlow et al., 2014; Rogers et al., 2016). Often it is not possible to compare studies or make generalisations (OSPAR, 2009; Wilcock et al., 2014). Here the aim is to aid the mitigation process by directing research priorities toward the most vulnerable fish species, and developing models and tools that allow for informed and cost-effective mitigation methods in a bid to reduce the effects of anthropogenic noise from marine traffic.
... The anthropogenically modified and engineered nature of most river systems in the UK and wider (Kemp and O'Hanley, 2010), (Figure 2.3) means that increasing consideration should be given to how these modifications may impact the acoustic environment of (typically shallow) freshwater habitats (Leighton et al. 2019). In addition to this, the modifications and anthropogenic structures around these environments mean that anthropogenic noise is far more likely to be generated (Slabbekoorn et al. 2010). ...
... The sources and characteristics of anthropogenic underwater noise pollution range from activities as diverse as pile driving during construction, which tends to produce high-intensity short-duration pulses (and may have acute consequences) to shipping, which generates moderate intensity levels over long durations and may lead to chronic effects (Slabbekoorn et al., 2010). The properties of sound propagation differ in water from those in air; in water it travels farther and faster and attenuates less. ...
... Rather than use play back of recordings of specific noise generating activities, such as shipping, which have been frequently employed to create the treatment conditions described in earlier experiments, the fish were exposed to a broadband frequency range (60 -2000 Hz). The broadband frequency used was selected to cover the hearing range expected of the European minnow based on current understanding for other similar species, for example fathead minnow (Scholik & Yan, 2001;, and to replicate anthropogenic-driven sound commonly encountered in aquatic environments (Slabbekoorn et al., 2010). Behaviours observed for the acoustic treatment were compared with those recorded prior to treatment. ...
Thesis
Anthropogenic structures in the aquatic environment can cause mortality, damage and ecological exclusion of fish. These anthropogenic threats are traditionally mitigated for by physical means of excluding, diverting and deterring fish. These methods are not entirely effective for all species and all life stages of fish. Increasingly, fisheries managers are turning to behavioural deterrents to supplement and replace these traditional technologies; however, quite often these devices are deployed with little scientific basis. Current understanding of fish behaviour in the presence of acoustic stimuli focuses on, often large-scale, experiments that aim to manipulate the placement of fish within a system. This management-led, deterrent-concentrated research misses many of the complex, and important, parts of the behaviour being displayed by these animals. The fundamental based approach of the research investigates the difference in reaction of individuals and groups of small cypriniform fish. Using finely measured acoustic treatments and high-definition video recording in an experimental flume, the European minnow (Phoxinus phoxinus) was exposed to differing acoustic treatments and the resultant footage was analysed. Results indicate that groups of fish are more uniformly impacted by sound than individuals and that they return to normal behaviour more slowly. The data also demonstrates that individuals within a group behave in a more coherent manner when initially exposed to sound. Where individuals did demonstrate changes in their behaviour, groups of fish did not demonstrate changes in the same metrics, namely swimming speed and persistence of swim paths. The research presented within this thesis has contributed to scientific understanding of how the placement of fish can be influenced by sound and also the fine scale behaviours that they present when exposed to an acoustic stimulus. Reactions of individual fish are compared with reactions of groups of fish and the significant differences between them are discussed. The information brought about by conducting this research will go towards furthering knowledge of the complex nature of animal behaviour and also the complexities of experimental acoustic work within water tanks.
... Anthropogenic noise is globally recognised as a cause for concern, and several international agreements exist with objectives to monitor and mitigate the impacts of underwater sound pollution on aquatic life (e.g. the Helsinki Commission, 1988;the OSPAR Convention, 1992;and the Marine Strategy Framework Directive, 2008). When combined with the biological relevance of sound to fish, the range of fish responses to this ubiquitous transboundary pollutant (Slabbekoorn et al., 2010) supports the use of acoustics as a viable mitigation tool in freshwater fisheries management (Popper and Carlson, 1998). ...
... Anthropogenic noise increasingly disrupts the acoustic environments in which aquatic organisms live (Slabbekoorn et al., 2010;Radford et al., 2014). Many sources of underwater noise exist including ships and recreational boats, seismic exploration, construction, naval sonar, and marine mammal deterrent devices. ...
... These impacts may differ greatly dependent on behavioural or functional processes which are specific to a certain life-stage, and critical to survival and functioning (Slabbekoorn et al., 2010). ...
Thesis
Rising levels of anthropogenic underwater sound may have negative consequences on freshwater ecosystems. Additionally, the biological relevance of sound to fish and observed responses to human-generated noise promote the use of acoustics in behavioural guidance technologies that are deployed to control the movement of fish. For instance, acoustic stimuli may be used to prevent the spread of invasive fishes or facilitate the passage of vulnerable native species at man-made obstructions. However, a strong understanding of fish response to acoustics is needed for it to be effectively deployed as a fisheries management tool, but such information is lacking. Therefore, this thesis investigated the group behavioural responses of cyprinids to acoustic stimuli. A quantitative meta-analysis and experimental studies conducted in a small-tank or large open-channel flume were used to address key knowledge gaps that are necessary to improve the sustainability of acoustic deterrent technologies, and assist in conservation efforts to reduce the negative impacts of anthropogenic noise. Current understanding on the impact of anthropogenic noise on fishes (marine, freshwater and euryhaline species) was quantified. The impact of man-made sound is greatest for fish experiencing anatomical damage, for adult and juveniles compared to earlier life-stages, and for fish occupying freshwater environments. These findings suggest a review of the current legislation covering aquatic noise mitigation which commonly focus on marine-centric strategies, thereby undervaluing the susceptibility of freshwater fish to the rising levels of anthropogenic sound. Limitations and knowledge gaps within the literature were also identified, including: 1) group behavioural responses to sound, 2) the response of fish to different fundamental acoustic properties of sound, 3) system longevity (e.g. habituation to a repeated sound exposure), and 4) site-specific constraints. Fish movement and space use were quantified using fine-scale behavioural metrics (e.g. swimming speed, shoal distribution, cohesion, orientation, rate of tolerance and signal detection theory) and their collective response to acoustics assessed using two approaches. First, a still-water small tank set-up allowed for the careful control of confounding factors while investigating cyprinid group response to fundamental acoustic properties of sound (e.g. complexity, pulse repetition rate, signal-to-noise ratio). Second, a large open-channel flume enabled the ability of a shoal to detect and respond to acoustic signals to be quantified under different water velocities. Shoals of European minnow (Phoxinus phoxinus), common carp (Cyprinus carpio) and roach (Rutilus rutilus) altered their swimming behaviour (e.g. increased group cohesion) in response to a simple low frequency tonal stimulus. The pulse repetition rate of a signal was observed to influence the long-term behavioural recovery of minnow to an acoustic stimulus. Furthermore, signal detection theory was deployed to quantify the impact of background masking noise on the group behavioural response of carp to a tonal stimulus, and investigate how higher water velocities commonly experienced by fish in the wild may influence the response of roach to an acoustic stimulus. Fine-scale behavioural responses were observed the higher the signal-to-noise ratio, and discriminability of an acoustic signal and the efficacy at which fish were deterred from an insonified channel was greatest under higher water velocities. The information presented in this thesis significantly enhances our understanding of fish group responses to man-made underwater sound, and has direct applications in freshwater conservation, fish passage and invasive species management.<br/
... contribute to a growing ambient sound level (Madsen et al., 2006;Popper and Hawkins, 2019a;Sertlek et al., 2019;Slabbekoorn et al., 2010;Tougaard et al., 2009;Tougaard et al., 2020;Wahlberg and Westerberg, 2005;Duarte et al., 2021). However, the most dramatic acoustic events are associated with the park's construction phase (Dahl et al., 2015;Lippert et al., 2018). ...
... Especially the sound event train with long periods of loud series of impulsive sounds associated with pile driving for turbine foundation placements have a high potential to negatively affect marine wildlife (Duarte et al., 2021;Popper and Hastings, 2009;Popper and Hawkins, 2019;Slabbekoorn, 2019;Slabbekoorn et al., 2010). The most common type of offshore turbine foundation is a steel monopile, that ranges in diameter from 4 to 8 m and is piled into the sediment from a rigid platform using a hydraulic hammer. ...
... Fish can be directly affected by pile driving through immediate physical and behavioural effects, or indirectly through the effect of piling on their predators (Thompson et al., 2020) and prey (Roberts et al., 2016). Exposure effects from multiple impulsive pile strikes at close range have been investigated in captivity and include damage to internal organs, including the inner ear, swim bladder, liver, kidney, and gonads (Casper et al., 2017(Casper et al., , 2013Halvorsen et al., 2012a,b), which may eventually result in fish death (Slabbekoorn et al., 2010;Popper and Hawkins, 2019). Acoustic modelling has recently demonstrated that lethal and sub-lethal injury could occur at distances as far as 1.8 and 3.1 km from the pile driving location, respectively (Ainslie et al., 2020). ...
Article
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Offshore energy acquisition through the construction of wind farms is rapidly becoming one of the major sources of green energy all over the world. The construction of offshore wind farms contributes to the ocean soundscape as steel monopile foundations are commonly hammered into the seabed to anchor wind turbines. This pile driving activity causes repeated, impulsive, low-frequency sounds, reaching far into the environment, which may have an impact on the surrounding marine life. In this study, we investigated the effect of the construction of 50 wind turbine foundations, over a time span of four months, on the presence and movement behaviour of free-swimming, individually tagged Atlantic cod. The turbine foundations were constructed at a distance ranging between 2.3-7.1 km from the cod, which resided in a nearby, existing wind farm in the southern North Sea. Our results indicated that local fish remained in the exposed area during and in-between pile-driving activities, but showed some modest changes in movement patterns. The tagged cod did not increase their net movement activity, but moved closer to the scour-bed (i.e. hard substrate), surrounding their nearest turbine, during and after each piling event. Additionally, fish moved further away from the sound source, which was mainly due to the fact that they were positioned closer to a piling event before its start. We found no effect of the time since the last piling event. Long-term changes in movement behaviour can result in energy budget changes, and thereby in individual growth and maturation, eventually determining growth rate of populations. Consequently, although behavioural changes to pile driving in the current study seem modest, we believe that the potential for cumulative effects, and species-specific variation in impact, warrant more tagging studies in the future, with an emphasis on quantification of energy budgets.
... Sound levels from a variety of anthropogenic activities may result in detrimental effects on marine organisms as humans' impact on the ocean soundscape has increased over the last century (e.g., Slabbekoorn et al., 2010;Carroll et al., 2017;Edmonds et al., 2016). Activities such as commercial shipping, pile driving, and the use of sonar and explosives can impact fitness, particularly in invertebrate and fish species that rely on sounddependent activities (e.g., Popper & Hawkins, 2019), for which there are still profound gaps in knowledge (Popper et al., 2021). ...
... In terms of chronic effects, crabs exposed to repeated boat noise over time (though of an uncharacterized sound field, so perhaps not representative) experienced an increase in stress measures like metabolic rate (Wale, Simpson & Radford, 2013a), and fishes exposed to long-term sound exposure show detriments in normal behaviors, desensitization to important environmental sounds, increases in physiological indicators like cortisol, and increased infection and parasitism (e.g., Anderson et al., 2011;Carroll et al., 2017;. These chronic effects are linked to decreased fitness , even though there is some evidence that stress indicators and responses to biologically important signals can lessen over time as animals become acclimated to chronic noise (Slabbekoorn et al., 2010;Armstrong-Smith, 2016;Pine et al., 2016). Of particular concern for chronic exposure to anthropogenic noise is the knowledge gap in vertebrate and invertebrate responses to that noise outlined recently regarding offshore wind development in New York State, USA (Popper et al., 2021). ...
Article
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Human usage of coastal water bodies continues to increase and many invertebrates face a broad suite of anthropogenic stressors ( e.g ., warming, pollution, acidification, fishing pressure). Underwater sound is a stressor that continues to increase in coastal areas, but the potential impact on invertebrates is not well understood. In addition to masking natural sound cues which may be important for behavioral interactions, there is a small but increasing body of scientific literature indicating sublethal physiological stress may occur in invertebrates exposed to high levels of underwater sound, particularly low frequency sounds such as vessel traffic, construction noise, and some types of sonar. Juvenile and sub-adult blue crabs ( Callinectes sapidus ) and American lobsters ( Homarus americanus ) were exposed to simulated low-frequency vessel noise (a signal was low-pass filtered below 1 kHz to ensure low-frequency content only) and mid-frequency sonar (a 1-s 1.67 kHz continuous wave pulse followed by a 2.5 to 4.0 kHz 1-s linear frequency modulated chirp) and behavioral response (the animal’s activity level) was quantified during and after exposure using EthoVision XT™ from overhead video recordings. Source noise was quantified by particle acceleration and pressure. Physiological response to the insults (stress and recovery) were also quantified by measuring changes in hemolymph heat shock protein (HSP27) and glucose over 7 days post-exposure. In general, physiological indicators returned to baseline levels within approximately 48 h, and no observable difference in mortality between treatment and control animals was detected. However, there was a consistent amplified hemolymph glucose signal present 7 days after exposure for those animals exposed to mid-frequency sound and there were changes to C. sapidus competitive behavior within 24 h of exposure to sound. These results stress the importance of considering the impacts of underwater sound among the suite of stressors facing marine and estuarine invertebrates, and in the discussion of management actions such as protected areas, impact assessments, and marine spatial planning efforts.
... Human activities are driving a precipitous increase in ocean noise levels (Frisk, 2012), which is recognized as a global threat to marine life (Duarte et al., 2021;Shannon et al., 2016). Numerous marine animals rely primarily on acoustic over visual signals and information because light penetration attenuates rapidly with depth, whereas sound transmission is enhanced underwater compared to in air (Popper & Hawkins, 2018;Slabbekoorn et al., 2010). Noise pollution can therefore disrupt critical behaviours of marine animals by shrinking communication and listening spaces, damaging sensory organs and inducing physiological stress (Andr e et al., 2011;Carter et al., 2020;Pine et al., 2020;Stanley et al., 2017;Wale et al., 2013). ...
... Recent research has highlighted that noise pollution is an important threat facing fish populations (Cox et al., 2018;Slabbekoorn et al., 2010). Noise affects fish throughout their life span and can impede critical functions such as shoaling, cooperation, parental care and learning (Ferrari et al., 2018;Herbert-Read et al., 2017;Nedelec, Mills, et al., 2017;. ...
Article
Anthropogenic noise pollution is an emerging global threat to fish populations. Among a suite of dele-terious effects, noise can potentially impede reproductive success in some fishes by masking their mate advertisement vocalizations. Using the plainfin midshipman fish, Porichthys notatus, a marine toadfish that produces a distinctive 'hum' during courtship, we investigated how noise affects male vocalizations and spawning success in the wild. We recorded nesting males for 3 days and measured the frequency (i.e. pitch), amplitude and duration of their vocalizations before, during and after exposure to artificial noise (~118 Hz tone). We also counted eggs in nests exposed to 10 days of artificial noise versus control nests that were not exposed to artificial noise. Males exposed to noise produced fewer vocalizations, reduced the frequency of vocalizations and increased the amplitude of their mating hum (Lombard effect). However, chronic artificial noise exposure did not significantly affect spawning success, suggesting that the Lombard effect allowed males to sustain clear advertisement signals when competing with a relatively weak artificial noise source. Future studies are needed to determine whether such vocal adjustments incur costs for males, and how common anthropogenic noises, such as boat engines, affect spawning and reproductive success.
... www.nature.com/scientificreports/ Anthropogenic underwater noise is increasing globally 16 and the primary source is vessel noise 17,18 . Baleen whales have been considered to be mostly affected by the lower frequencies of vessel noise [19][20][21] . ...
... Study area and species. Fieldwork was conducted in 2020 and 2021 off the western side of Tenerife, Canary Islands (Spain; Fig. 1), within the special conservation area Franja Teno-Rasca (European Union Natura 2000 Network ES7020017; 28.193200° N, 16.891800° W). ...
Article
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Vessel noise is a primary driver of behavioural disturbance in cetaceans, which are targeted during whale-watch activities. Despite the growing, global effort for implementing best-practice principles, to date, there are no regulations on whale-watch vessel noise levels. Here, we test the hypothesis that a whale-watch vessel with a low noise emission will not elicit short-term behavioural responses in toothed whales compared to a vessel with a louder engine. We measured behavioural responses (n = 36) of short-finned pilot whales ( Globicephala macrorhynchus ) to whale-watch vessel approaches (range 60 m, speed 1.5 kn). Treatment approaches with a quieter electric engine (136–140 dB) compared to the same vessel with a louder petrol engine (151–139 dB) (low-frequency–mid-frequency weighted source levels, re 1 µPa RMS @ 1 m) were examined. Focal whales were resting mother and calves in small group sizes. During petrol engine treatments, the mother’s mean resting time decreased by 29% compared to the control (GLM, p = 0.009). The mean proportion of time nursing for the calf was significantly influenced by petrol engine vessel passes, with a 81% decrease compared to the control (GLM, p = 0.01). There were no significant effects on behaviour from the quieter electric engine. Thus, to minimise disturbance on the activity budget of pilot whales, whale-watch vessels would ideally have source levels as low as possible, below 150 dB re 1 µPa RMS @ 1 m and perceived above ambient noise.
... These sounds are important to many marine animals, which may rely on auditory cues for communication, orientation, feeding, or detection of predators. Recently, human activities have become another prominent source of underwater noise, altering the soundscape and increasing the background noise level in many local environments (Andrew et al., 2002;Duarte et al., 2021;Hildebrand, 2009;McDonald et al., 2006;Slabbekoorn et al., 2010). ...
... It is estimated that the noise from shipping increased at a rate of 3 dB per decade from 1950 to 2000, which means that the intensity of ambient noise underwater doubled every 10-year (Jones, 2019). These increasing underwater noise levels are thought to have physiological influences on animals and broadly affect the ocean ecosystem (reviewed in Slabbekoorn et al., 2010). In the 13th meeting of the Conference of the Parties to the Convention on Biological Diversity (CBD-COP13; Cancun, Mexico, 4-17 December 2016), anthropogenic underwater noise was highlighted as a critical and urgent issue for the next one hundred years. ...
Article
Anthropogenic underwater noises that change aquatic soundscapes represent an important issue in marine conservation. While it is evident that strong underwater acoustic pollutants may cause significant damage to fish at short ranges, the physiological effects of long-term exposure to relatively quiet but continuous noise are less well understood. Here, we present a summary of the known impacts of long-term underwater noise on hypothalamic-pituitary-interrenal (HPI) axis-mediated physiological responses, oxidant/antioxidant balance, and neurotransmitter regulation in fish. Cortisol is known to play a central role in physiological stress response, most often as a mediator of acute response. However, recent research indicates that noise exposure may also induce chronic corticosteroid responses, which involve increased rates of cortisol turnover. Moreover, continuous noise affects oxidative stress and antioxidant systems in vertebrates and fish, suggesting that oxidative species may mediate some noise-induced physiological responses and make these systems valuable noise stress markers. Lastly, noise stress is also known to affect neurotransmitters in the brain that may cause neurophysiological and behavioral changes. The neurochemical mechanisms underlying observed behavioral disorders in fish after exposure to changing acoustic environments are a topic of active research. Overall, a growing body of evidence suggests that chronic noise pollution could be a threat to fish populations. In future work, systematic and comparative investigations into long-term and transgenerational adaptive neuronal and metabolic responses to noise will be important to understand the physiological patterns and dynamics of noise response relevant to fish conservation.
... While PAM does require a species make species-specific sounds while spawning, a large number of fish species have been shown to incorporate sounds in their spawning behaviour (Kasumyan, 2009;Ladich, 2004) making this a promising monitoring tool. The use of PAM can also be worthwhile for examining effects of anthropogenic disturbances on natural spawning activity; a growing problem of global concern (Nolet, 2017;Slabbekoorn et al., 2010). While PAM has been extensively used in marine habitats, it is less prevalent for freshwater monitoring; however, this use has been increasing in recent years (e.g. ...
... Sturgeon hearing is most sensitive below 300 Hz and they may be essentially deaf to any frequencies above 500 Hz (Lovell et al., 2005) which may make them especially vulnerable/sensitive to noise of the commercial freighters passing overhead and unable to hear the higher frequency recreational boats. There is increasing F I G U R E 8 The relationship between the presence of high frequency boat sounds and the (a) overall and (b) maximum calling rate of Lake Sturgeon as well as the relationship between the presence of low frequency boat sounds and the (c) overall and (d) maximum calling rate of Lake Sturgeon interest in possible effects of shipping activity on fish behaviour and survival (e.g., Haren, 2007;Neenan et al., 2016;Slabbekoorn et al., 2010) and while our data are not conclusive they do suggest more studies should be conducted to quantify possible effects of shipping during spawning of this threatened family of fish. ...
Article
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Lake sturgeon (Acipenser fulvescens) are endangered in the Laurentian Great Lakes with increasing binational efforts to establish spawning grounds to aid restoration. While SCUBA surveys can document spawning activity, these are labour‐intensive and may disrupt spawning. We used passive acoustic monitoring to quantify spawning sounds of lake sturgeon as a first step to developing remote sensing of sturgeon spawning grounds. Acipenser sp. are known to make a variety of sounds including, “thunders” (aka drums), which have been documented in A. fulvescens during spawning. We quantified drums from a known spawning bed. We recorded 5 different potential sturgeon sounds but only quantified drums as a marker for spawning activity. Drums were low frequency with average frequency peaks at 40 and 92 Hz and a rapid drop‐off thereafter. There was no relationship between calling activity and water temperature but calling activity increased as the summer progressed. Call production was most active from 0600 to 1500 h with little calling activity during nighttime recordings. The presence of low frequency boat sounds did correlate with a reduction in maximum calling rate so it is possible that commercial shipping may disrupt sturgeon communication, but more research is necessary to separate correlational from causative effects. These recordings represent a promising approach to map sturgeon spawning activity and show the potential effect of human activity on communication in this threatened species.
... Human activities, such as commercial shipping, military activities, or scientific exploration of the seabed inevitably introduce a certain amount of noise energy into marine ecosystems. Its impact can harm marine mammals (MMC 2007), sea birds (Crowell 2016), and fish (Slabbekoorn et al. 2010). ...
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One of the United Nations Sustainable Development Goals regarding "conservation and sustainable use of the oceans, seas, and marine resources" emphasizes the urgency of eliminating harmful effects on the sea and its biota, where the role of anthropogenic activities is crucial. The global trend of merchant shipping is increasing, thus enlarging underwater noise levels. As a result, greater noise can harm aquatic animals in their habitats. In the Baltic Sea, the underwater sound pressure levels are now being evaluated utilizing noise measurement, modelling, and mapping. In areas such as narrow ship passages, namely lagoons, channels, or straits, the ambient underwater noise modelling becomes very complex, even though these EU inland waters are regarded by legislation as part of the marine basin. For instance, the Klaipėda Channel (Klaipėda Strait), connecting the Baltic Sea and the Curonian Lagoon, is regarded by the national Lithuanian legislation as part of marine waters, where the environmental status should be evaluated according to the EU Maritime Strategy Framework Directive. In this narrow channel, an alternative to the modelling of ambient sound pressure levels can be applied to understand the long-term trends of vessel-sourced noise emissions. In this paper, an example of application of ship noise emission modelling for a narrow Klaipėda Harbour area is presented, along with the results obtained throughout 2015-2017. The modelled noise levels in the harbour area reached the median levels of 112.5 dB in 2015 and 102.6 dB re 1 µPa 2 in 2017. The maximum emitted instantaneous sound pressure levels by ships reached 173.7 dB in 2015 and 179.4 dB re 1 µPa 2 in 2017 in the area of interest.
... Concerns surrounding the influx of anthropogenic noise, particularly behavioural and physiological impacts on a wide variety of marine taxa, have increased considerably in recent decades (Cox et al., 2018;Duarte et al., 2021;Simpson et al., 2016;Slabbekoorn et al., 2010). Broadly speaking, fish are underrepresented in studies on the ecological effects of anthropogenic noise (Williams et al., 2015a), even though fish are ecologically, culturally, and economically important. ...
Article
There is growing concern about impacts of ship and small boat noise on marine wildlife. Few studies have quantified impacts of anthropogenic noise on ecologically, economically, and culturally important fish. We conducted open net pen experiments to measure Pacific herring (Clupea pallasii) and juvenile salmon (pink, Oncorhynchus gorbuscha, and chum, Oncorhynchus keta) behavioural response to noise generated by three boats travelling at different speeds. Dose-response curves for herring and salmon estimated 50% probability of eliciting a response at broadband received levels of 123 and 140 dB (re 1 μPa), respectively. Composite responses (yes/no behaviour change) were evaluated. Both genera spent more time exhibiting behaviours consistent with anti-predator response during boat passings. Repeated elicitation of vigilance or anti-predatory responses could result in increased energy expenditure or decreased foraging. These experiments form an important step toward assessing population-level consequences of noise, and its ecological costs and benefits to predators and prey.
... Anthropogenic sound is almost omnipresent in the marine environment and has the potential to affect marine animals across taxa Slabbekoorn et al., 2010). Animals use and produce sound for orientation and communication and these functions can be undermined by masking or disturbing noise (Gordon et al., 2019;Wilson et al., 2014). ...
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Anthropogenic sound has been shown to affect marine animals across taxa. However, bivalves and other invertebrates have received limited attention, and most studies across taxa have focussed on immediate, rather than long-term, effects of sound. Most bivalves adopt a sessile or sedentary lifestyle and are therefore likely to be subject to frequent exposure to the same anthropogenic sounds. For this reason, bivalves are an especially relevant taxonomic group to study with regards to potential long-term effects of sound. In the current study, we examined whether blue mussels (Mytilus edulis) habituate to repeated sound exposures and whether they recover quicker from a single pulse exposure than from a pulse train. We equipped individual mussels with sensors to monitor their valve gape and exposed them to repeated sound playback. We found that mussels responded to sound by partially closing their valves. This response was consistent and repeatable, and decayed over sequential exposures to the same sound stimulus. A stimulus specificity test, meant to determine whether the decayed response could be attributed to habituation or more general sensory adaptation, yielded interesting but ambiguous results. Additionally, we found no differences in the initial response and recovery (time to return to baseline levels) between mussels that were exposed to single pulses and pulse trains. Our results therefore show that mussels reduce responsiveness over sequential exposures and that mussels mostly respond to the onset of a pulse train. Future research is needed to determine whether mussels habituate in situ to actual anthropogenic sound and whether a lack of a behavioural response to repeated sound also implies a lack of other negative effects, such as physiological changes and mortality.
... Noise pollution is a ubiquitous form of marine pollution and it is particularly acute on busy maritime routes. Long-term exposure to intensive sound results in the modification of behaviour and habitat use by some fish and mammal species (Bass and McKibben, 2003;Nimak et al., 2007;Rako et al., 2013;Slabbekoorn et al., 2010;Wysocki et al., 2009). A review encompassing various human-produced underwater noise sources found noise impacts on the development of fish and invertebrates including anatomical and physiological effects affecting the population biology and ecology of the concerned species and a decrease of the ecological services performed by these animals and a loss of fishing opportunities (Weilgart, 2018). ...
Article
The intensive growth of cruise tourism worldwide during recent decades is leading to growing concerns over the sector's global environmental and health impacts. This review combines for the first time various sources of information to estimate the magnitude of the cruise industry's environmental and public health footprints. This research shows that cruising, despite technical advances and some surveillance programmes, remains a major source of air, water (fresh and marine) and land pollution affecting fragile habitats, areas and species, and a potential source of physical and mental human health risks. Health risks impact both the people on board (crew and passengers) and on land (workers of shipyards where cruise ships are dismantled and citizens inhabiting cities with cruise ports and shipyards). In this context, we argue that the cruise industry should be held accountable with more monitoring and regulation to prevent or minimize the growing negative environmental and human health impacts.
... Nowacek et al. 2007;Weilgart 2007), with some research on teleost fishes (e.g. Slabbekoorn et al. 2010;Mickle and Higgs 2018) but little effort has been devoted to the role of acoustics in elasmobranchs (Chapuis et al. 2019). Overfishing of elasmobranch populations exceeds the implementation of fisheries management and trade guidelines (Pacoureau et al. 2021), so efforts to reduce bycatch are increasingly seen as important. ...
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Elasmobranchs are of important global conservation concern, however their hearing abilities, use of sound, and responses to anthropogenic noise pollution are all vastly understudied, despite noise pollution being an ever-increasing concern to global fish populations. This review focuses on the hearing ability of elasmobranchs and their attraction and avoidance response to sound. The benefits and drawbacks of field vs laboratory studies are discussed in this review, along with an estimate of the minimum sound detection distance of elasmobranchs (using lemon sharks as a model). Some important practical applications of sound on elasmobranch conservation efforts are outlined (potential deterrence for bycatch and the rare occurrence of shark attacks) and future research suggestions are provided.
... Semi-aquatic environments differ from terrestrial environments in terms of temperature, pressure, and density, all of which will affect how signals travel. Water density causes the sound to travel faster, but in a lower and narrower band peak frequency, dampening especially loud sounds, as found to occur in signals produced by the water boatmen species Corixa dentipes and C. punctata (Family Corixidae [53,55,87,88]). These pulses are emitted at a relatively narrow band peak frequency of 1.5-2.8 ...
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Sexual selection is a major evolutionary process, shaping organisms in terms of success in competition for access to mates and their gametes. The study of sexual selection has provided rich empirical and theoretical literature addressing the ecological and evolutionary causes and consequences of competition for gametes. However, there remains a bias towards individual, species-specific studies, whilst broader, cross-species comparisons looking for wider-ranging patterns in sexual selection remain uncommon. For instance, we are still some ways from understanding why particular kinds of traits tend to evolve under sexual selection, and under what circumstances. Here we consider sexual selection in the Heteroptera, a sub-order of the Hemiptera, or true bugs. The latter is the largest of the hemimetabolous insect orders, whilst the Heteroptera itself comprises some 40,000-plus described species. We focus on four key sexual signaling modes found in the Heteroptera: chemical signals, acoustic signaling via stridulation, vibrational (substrate) signaling, and finally tactile signaling (antennation). We compare how these modes vary across broad habitat types and provide a review of each type of signal. We ask how we might move towards a more predictive theory of sexual selection, that links mechanisms and targets of sexual selection to various ecologies.
... Consequently, the impact of machine-generated sounds on the environment has become an increasingly popular subject of investigation (Jerem and Mathews, 2021) with considerable evidence of its negative influence on animal behavior (Brumm and Slabbekoorn, 2005;Habib et al., 2007), community ecology (Francis et al., 2009), and species habitats (Nowacek et al., 2007;Barber et al., 2010;Chan et al., 2010;Slabbekoorn et al., 2010;Mullet et al., 2017a). Because of their human origin, machine-generated sounds fit within the ecoacoustics category of anthropophony, but more exclusively under the subcategory of technophony (Mullet et al., 2016). ...
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Humans categorize unwanted sounds in the environment as noise. Consequently, noise is associated with negative human and ecological values, especially when it is derived from an anthropogenic source. Although evidence confirms that many machine-generated anthropogenic sounds have negative impacts on animal behavior and communication, natural sources of non-biological sound, such as wind, rain, running water, and sea waves (geophonies) have also been categorized as noise and are frequently dismissed or mischaracterized in acoustic studies as an outside factor of acoustic habitats rather than an integrated sonic component of ecological processes and species adaptations. While the proliferation of machine-generated sound in the Biosphere has become an intrusive phenomenon in recent history, geophony has shaped the Earth’s sonic landscapes for billions of years. Therefore, geophonies have very important sonic implications to the evolution and adaptation of soniferous species, forming essential ecological and semiotical relationships. This creates a need to distinguish geophonies from machine-generated sounds and how species respond to each accordingly, especially given their acoustic similarities in the frequency spectrum. Here, we introduce concepts and terminology that address these differences in the context of ecoacoustics. We also discuss how Acoustic Complexity Indices (ACIs) can offer new possibilities to quantifiably evaluate geophony in relation to their sonic contest.
... Broadly speaking, masking can affect communication, navigation and predator detection in marine animals. Masking potentially has an important impact on marine taxa because, (i) it can be long-lasting (chronic), and (ii) it affects the 'acoustic habitat' of an animal which can impair both the active and passive usage of sound over considerable ranges (Clark et al., 2009;Slabbekoorn et al., 2010). masking, as well as hearing characteristics and strategies to reduce masking effects. ...
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Anthropogenic underwater noise impacts have become a hot topic for environmental managers and regulators in Europeand beyond. Sounds from human activity at sea include shipping and other marine craft, construction and installations, sonar and seismic surveys. This Future Science Brief presents an update on the previous EMB publication on underwater noise, Position Paper N° 13 on “The effects of anthropogenic sound on marine mammals: A draft research strategy". This Future Science Brief expands the scope of the discussion beyond marine mammals to fishes and invertebrates, and outlines key developments that have taken place since the Position Paper’s publication. The main chapters of the document focus on: the advances in our knowledge on anthropogenic underwater sound in the Ocean; the new knowledge that has been developed on the effects of noise on marine organisms; and the measures that have been taken to address the issue of underwater noise. While significant progress has been made, knowledge gaps still remain. The document therefore presents these outstanding issues and highlights priority actions for addressing them. This Future Science Brief states that the most urgent priority actions/questions are to: 1. Develop collaborative international standards applicable to all steps of the risk framework; 2. Conduct comprehensive monitoring combined with spatial ecological modelling of marine species’ dynamic habitat use, movements, behaviour and distribution to establish baselines; 3. Foster comprehensive monitoring and data collection of current soundscapes / ambient noise, including via joint monitoring programmes in existing and new areas; 4. Shortlist high priority (and biologically relevant) sound sources and perform standardized source characterization studies; 5. Undertake hearing studies on baleen whales and on selected fish and invertebrate species; 6. Conduct field and modelling studies on changes in acoustic habitats to identify masking risks to communication in fishes and marine mammals; 7. Conduct further studies on behavioural response of marine mammals and fishes due to exposure to high intensity impulsive sounds to assess population consequences; 8. Conduct taxa-relevant studies on hearing impairment and physiological stress to address existing knowledge gaps in invertebrates, fishes and marine mammals; 9. Conduct dedicated studies including multi-species investigations, predator-prey interactions, and interaction with other food web levels, addressing the question of how noise impacts combine with other stressors; 10. Develop frameworks and conduct studies to allow population-level assessment of effects from cumulative impact of noise and other pressures; 11. Conduct dedicated modelling and field studies to improve understanding on effectiveness, safety and cost-effectiveness of noise mitigation devices, mitigation measures and management options; 12. Develop regional action plans and guidelines for Environmental Impact Assessment and policies; and 13. Initiate international collaborative transdisciplinary projects to develop stakeholder and societal capacity in understanding and addressing underwater noise.
... Shipping may also have impacts through mechanisms such as ship strikes and noise. Although studies on fish are relatively limited, strikes have been documented in some larger species (e.g., Schoeman et al., 2020) and negative effects of anthropogenic sounds on fish behavior (e.g., impedance of predator detection) and physiology are documented in a review of the impacts of rising underwater sound levels on fish by Slabbekoorn et al. (2010). Thus, potential exists for adding to the overall mortality in the marine environment. ...
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Conservation and management of anadromous salmonids are enhanced by understanding timing, spatial extent, and occupied depths and temperatures in marine feeding habitats. We examined ocean-entry timing and marine habitat-use, and their association with environmental conditions (e.g., sea-ice and sea-surface temperatures (SSTs)) of anadromous Dolly Varden (Salvelinus malma malma) from the Canadian Arctic using pop-up satellite archival tags (PSAT) and data storage tags. Using this information, we evaluated the extent tagged fish occupied offshore (>5 km) habitats, and their proximity to a marine protected area (MPA) and areas of potential threats in the Canadian Beaufort Sea. Ocean-entry by tagged fish using the western Mackenzie Delta for freshwater migration occurred approximately mid-June (range = 8–26 June) and closely followed landfast sea-ice break-up based on satellite imagery. While at sea, fish predominately occupied surface waters (<2 m) at SSTs of 5–10 °C. PSAT end-locations were 37–152 km offshore, typically near the sea-ice edge, greatly extending previously reported distances from shore in the Alaskan Beaufort Sea. The spatial extent of offshore dispersal by Dolly Varden is likely influenced by SSTs and sea-ice conditions, and the physical properties of the Mackenzie River plume (e.g., turbidity), which extends preferred temperatures farther from shore. In relatively cooler years characterized by later sea-ice breakup and a summer sea-ice margin situated closer to shore, fish spent more time in nearshore than offshore habitats (51.7% vs. 48.3%) compared to warmer years (12.6% vs. 87.5%). Furthermore, fish typically occupied shallower offshore mean depths (2.2 m vs. 3.4 m) of the water column and experienced colder mean water temperatures (5.1 °C vs. 7.4 °C) in cooler versus warmer years. Dolly Varden were found within or adjacent to hydrocarbon lease areas and shipping lanes, and may be vulnerable to threats associated with these activities. Although PSATs reported outside of the MPA boundaries, which are situated adjacent to the Mackenzie Delta, occupancy in spring was inferred during ocean-entry and while transitioning to offshore areas. This first study to describe how environmental conditions influence marine distribution of Canadian Dolly Varden together with their proximity to anthropogenic threats is relevant for assessing impacts of climate change and future development.
... PAM has been applied in both freshwater and marine environments [4,6] and proven to be a useful method in detecting and recording the calls of a variety of aquatic animals, such as whales [10,20], dolphins and porpoises [6,21,22], seals [23,24], and fish [4,25,26]. There are over 800 species of soniferous fishes [27][28][29][30][31][32], so PAM is a very useful method for collecting spatial and temporal data on many of those species in a non-invasive, continuous way. For example, PAM has been used to characterize oyster toadfish (Opsanus tau) boat whistle activity (daily, seasonal, and geographical), characteristics (amplitude, waveforms, and spectra), and propagation [1], to determine distinct diel and seasonal calling patterns of white-spotted damselfish (Dascyllus albisella) [33], and to locate grouper, Epinephelidae [34], and red drum (Sciaenops ocellatus) [35] spawning sites. ...
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Passive acoustic monitoring is a method that is commonly used to collect long-term data on soniferous animal presence and abundance. However, these large datasets require substantial effort for manual analysis; therefore, automatic methods are a more effective way to conduct these analyses and extract points of interest. In this study, an energy detector and subsequent pre-trained neural network were used to detect and classify six fish call types from a long-term dataset collected in the northern Gulf of Mexico. The development of this two-step methodology and its performance are the focus of this paper. The energy detector by itself had a high recall rate (>84%), but very low precision; however, a subsequent neural network was used to classify detected signals and remove noise from the detections. Image augmentation and iterative training were used to optimize classification and compensate for the low number of training images for two call types. The classifier had a relatively high average overall accuracy (>87%), but classifier average recall and precision varied greatly for each fish call type (recall: 39–91%; precision: 26–94%). This coupled methodology expedites call extraction and classification and can be applied to other datasets that have multiple, highly variable calls.
... This choice mainly depends on its impacts on fish catch. Several studies have shown that fish are sensitive to noise, especially anthropogenic noise [73][74][75][76][77] , which might potentially reduce the fish catch in nets, thereby reducing its adoption success by the fishers. Our study found that the catch per unit effort of fish was not significantly different between pingered and non-pingered nets, similar to results from the marine environment 62,78,79 . ...
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Ganges River dolphins echolocate, but this mechanism is inadequate for poor sonar-echoing objects such as the monofilament gillnets, causing considerable net entanglement related mortalities. Net entanglement related deaths are one of the major causes of cetacean population decline around the world. Experiments were carried out to understand the use of pingers—an acoustic deterrent, in aiding the deterrence of dolphins from fishing nets. Based on the dolphin clicks recorded, in an experimental setup spanning 36 days, a 90% deterrence was found; 22.87 ± 0.71 SE dolphin detection positive minutes per hour near non-pingered nets versus 2.20 ± 0.33 SE per hour near pingered net. Within 30 m radii of nets, visual encounters of non-calf reduced by 52% and calf by 9%, in the presence of pingers. No evidence of habituation to pingers, habitat avoidance in dolphins after pinger removal or a change in fish catch in nets because of pingers was found during the study. While the effectiveness of pingers on calves and fish catch needs further experimentation, the use of pingers to minimize net entanglement mortalities in the Ganges River dolphins seems to be the most promising solution currently available. These results have critical implications for the conservation of other species of river dolphins around the world.
... Panel C shows that environmental enrichment by playing Vivaldi music for 15 days evokes anxiolytic-like behavior, based on Barcellos et al. (2018). and predator-prey interactions (Radford et al., 2014;Slabbekoorn et al., 2010;Popper and Hastings, 2009). For example, long-term vibration impairs skeletal development of larvae, causing growth retardation vs. normal controls (Franz-Odendaal and Edsall, 2018), likely involving the heat shock protein signaling (Connolly and Hall, 2008). ...
Article
Strongly affecting human and animal physiology, sounds and vibration are critical environmental factors whose complex role in behavioral and brain functions necessitates further clinical and experimental studies. Zebrafish are a promising model organism for neuroscience research, including probing the contribution of auditory and vibration stimuli to neurobehavioral processes. Here, we summarize mounting evidence on the role of sound and vibration in zebrafish behavior and brain function, and outline future directions of translational research in this field. With the growing environmental exposure to noise and vibration, we call for more active use of zebrafish models for probing neurobehavioral and bioenvironmental consequences of acute and long-term exposure to sounds and vibration in complex biological systems.
... Following acclimation, mussels were randomly assigned to a control and two anthropogenic noise input groups. The ambient condition without any additional anthropogenic sound input serviced as the control, while the underwater sound pressure levels of the two anthropogenic noise input groups were set at ∼70 and ∼100 dB re 1 µPa to mimic the underwater conditions with different degrees of anthropogenic sound, according to previous studies (Hildebrand, 2009;Slabbekoorn et al., 2010;Peng et al., 2016). The pile-driving sound recorded previously (Solan et al., 2016) was used as the source of anthropogenic noise input in this study. ...
Article
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The increasing underwater noise generated by anthropogenic activities has been widely recognized as a significant and pervasive pollution in the marine environment. Marine mussels are a family of sessile bivalves that attach to solid surfaces via the byssal threads. They are widely distributed along worldwide coastal areas and are of great ecological and socio-economic importance. Studies found that anthropogenic noise negatively affected many biological processes and/or functions of marine organisms. However, to date, the potential impacts of anthropogenic noise on mussel byssal attachment remain unknown. Here, the thick shell mussels Mytilus coruscus were exposed to an ambient underwater condition (∼50 dB re 1 μPa) or the playbacks of pile-driving noise (∼70 or ∼100 dB re 1 μPa) for 10 days. Results showed that the noise significantly reduced the secretion of byssal threads (e.g., diameter and volume) and weakened their mechanical performances (e.g., strength, extensibility, breaking stress, toughness and failure location), leading to a 16.95–44.50% decrease in mussel byssal attachment strength. The noise also significantly down-regulated the genes expressions of seven structural proteins (e.g., mfp-1, mfp-2, mfp-3, mfp-6, preCOL-P, preCOL-NG, and preCOL-D) of byssal threads, probably mediating the weakened byssal attachment. Given the essential functions of strong byssal attachment, the findings demonstrate that the increasing underwater anthropogenic noise are posing a great threat to mussel population, mussel-bed community and mussel aquaculture industry. We thus suggest that future work is required to deepen our understanding of the impacts of anthropogenic noise on marine invertebrates, especially these with limited locomotion ability, like bivalves.
... Over the last century, as human activities in the ocean have increased, so has underwater ambient noise (Dahl et al., 2007;Slabbekoorn et al., 2010;Chapman and Price, 2011;Frisk, 2012), in part due to offshore wind power plants construction activities. It is therefore important to assess the noise impact, including the measurements of pile driving noise levels, and investigate their propagation properties as a function of distance in an underwater waveguide. ...
Article
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Offshore wind power plants are under construction worldwide, and concerns about the adverse effects of underwater noise generated during their construction on the marine environment are increasing. As part of an environmental impact assessment, underwater noise generated by impact pile driving was measured during the construction of an offshore wind farm off the southwest coast of Korea. The sound exposure levels of impact pile driving noise were estimated as a function of distance and compared with those predicted by a damped cylindrical spreading model and broadband parabolic equation simulation. Source level at 1 m was estimated to be in a range of 183–184 dB re 1μPa ² s in the sound exposure level based on the model predictions and it tended to decrease by 21 log ⁡ r as the distance increased. Finally, the spatial distribution of impact pile driving noise was predicted. This result, if combined with noise-induced damage thresholds for marine life, may be used to assess the effects of wind farm construction on marine ecosystems.
... The reason to understand underwater sound is that sounds and vibrations provide a great deal of important information to animals about their environment, potential mates, competitors, predators, and prey, just as sound in air is critical for the lives of all terrestrial animals (e.g., Fay and Popper, 2000;Slabbekoorn et al., 2010;Hawkins and Popper, 2018;Slabbekoorn, 2018). Indeed, sound is an essential communication channel for aquatic vertebrates and many aquatic invertebrates (reviewed in Hawkins et al., 2015;. ...
Article
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There are substantial knowledge gaps regarding both the bioacoustics and the responses of animals to sounds associated with pre-construction, construction, and operations of offshore wind (OSW) energy development. A workgroup of the 2020 State of the Science Workshop on Wildlife and Offshore Wind Energy identified studies for the next five years to help stakeholders better understand potential cumulative biological impacts of sound and vibration to fishes and aquatic invertebrates as the OSW industry develops. The workgroup identified seven short-term priorities that include a mix of primary research and coordination efforts. Key research needs include the examination of animal displacement and other behavioral responses to sound, as well as hearing sensitivity studies related to particle motion, substrate vibration, and sound pressure. Other needs include: identification of priority taxa on which to focus research; standardization of methods; development of a long-term highly instrumented field site; and examination of sound mitigation options for fishes and aquatic invertebrates. Effective assessment of potential cumulative impacts of sound and vibration on fishes and aquatic invertebrates is currently precluded by these and other knowledge gaps. However, filling critical gaps in knowledge will improve our understanding of possible sound-related impacts of OSW energy development to populations and ecosystems.
... While the impact of intense short-term noise on a number of different taxa has been well-documented (e.g. [3,42,51,64]), there remains a lack of confidence in the impacts of long-term exposure to low-frequency (< 300 Hz) noise [45,61]. This is out of step with the pervasive and persistent nature of continuous low-frequency noise generated by commercial shipping, in particular in the northern hemisphere [10,28]. ...
Article
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European waters presents Member States (MS) with a significant challenge in measurement and monitoring of a suite of descriptors of GES, some of which are poorly understood. To address the burden for MSs of monitoring and measuring environmental status and trends over vast areas, provisions have been made for the use of risk-based approaches to assessment and monitoring. Here, a standardised risk-based approach is described, aligned with the articles of the directive and with the DAPSI(W)R(M) conceptual frame. This risk approach is then applied at two different spatial scales for the risks associated with continuous underwater noise (D11C2). The first case is a subregional scale application for the North East Atlantic assessing risk under data poor conditions while the second case focuses on the Bay of Biscay, using the same process but under data rich conditions. The parallel applications of the risk-based approach illustrate that it is a powerful tool that can provide useful outputs , even where significant data gaps and limitations in understanding exist. We demonstrate the adaptability and wider applicability of the risk-based approach and finally make recommendations as to how improvements in data availability and accessibility could increase the confidence in the outputs.
... It is also important to note that underwater noise or artificial light associated with anthropogenic activities has been classified as a form of pollution and has attracted the attention of the scientific community. For detailed information on how underwater noise pollution affects fish, several reviews can be considered (Slabbekoorn et al. 2010, Becker et al. 2013, Cox et al. 2016, Popper & Hawkins 2016, Roberts et al. 2016, Rako-Gospić & Picciulin 2019. ...
Chapter
This chapter addresses the use of fish as indicators of environmental health. The main anthropogenic pressures impacting estuarine fishes are reviewed, as well as the main types of responses by fishes at different levels of biological organisation. Fishes have been widely used to assess estuarine health through different methodological approaches, namely comparisons with historical data or reference conditions, experimental approaches, environmental impact or risk assessment methods, as well as qualitative or quantitative indicators and models. A large number of multi‐metric indices based on fish have been proposed and are routinely used in environmental assessments, although to disentangle natural variability from anthropogenic pressures in a multi‐stress context of global change is still a major challenge.
... Most evidence of the impact of sensory pollution on sexual selection pressures comes from the acoustic domain, where low-frequency anthropogenic noise typically masks acoustic signals, such as songs or advertisement calls (Barber, Crooks & Fristrup, 2010). Many studies have documented reduced communication efficacy across a wide range of taxa (Tables 1 and S1), including in birds (Halfwerk et al., 2011;Grabarczyk & Gill, 2019), frogs (Bee & Swanson, 2007), and fish (Vasconcelos, Amorim & Ladich, 2007;Slabbekoorn et al., 2010). In great tits (Parus major), low-frequency song features, which are important in female attraction, are masked by anthropogenic noise (Halfwerk et al., 2011). ...
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Urbanisation can affect mating opportunities and thereby alter inter-and intra-sexual selection pressures on sexual traits. Biotic and abiotic urban conditions can influence an individual's success in pre-and post-copulatory mating, for example through impacts on mate attraction and mate preference, fertilisation success, resource competition or rival interactions. Divergent sexual selection pressures can lead to differences in behavioural, physiological, morphological or life-history traits between urban and non-urban populations, ultimately driving adaptation and speciation. Most studies on urban sexual selection and mating interactions report differences between urban and non-urban populations or correlations between sexual traits and factors associated with increased urbanisation, such as pollution, food availability and risk of predation and parasitism. Here we review the literature on sexual selection and sexual traits in relation to urbanisation or urban-associated conditions. We provide an extensive list of abiotic and biotic factors that can influence processes involved in mating interactions, such as signal production and transmission, mate choice and mating opportunities. We discuss all relevant data through the lens of two, non-mutually exclusive theories on sexual selection, namely indicator and sensory models. Where possible, we indicate whether these models provide the same or different predictions regarding urban-adapted sexual signals and describe different experimental designs that can be useful for the different models as well as to investigate the drivers of sexual selection. We argue that we lack a good understanding of: (i) the factors driving urban sexual selection; (ii) whether reported changes in traits result in adaptive benefits; and (iii) whether these changes reflect a short-term ecological, or long-term evolutionary response. We highlight that urbanisation provides a unique opportunity to study the process and outcomes of sexual selection, but that this requires a highly integrative approach combining experimental and observational work.
... This masking effect can reduce feeding success and increase the energy required to locate prey (Marley 2017). Fish can also be negatively affected by anthropogenic noise through disruption of schooling or spawning behaviors and shifting the hearing threshold (Slabbekoorn et al. 2010). Ship noise is the most ubiquitous and pervasive anthropogenic noise source in oceans (Erbe et al. 2019). ...
Article
The associations between feeding activities and environmental variables inform animal feeding tactics that maximize energetic gains by minimizing energy costs while maximizing feeding success. Relevant studies in aquatic animals, particularly marine mammals, are scarce due to difficulties in the observation of feeding behaviors in aquatic environments. This data scarcity concurrently hinders ecosystem‐based fishery management in the context of small toothed‐cetacean conservation. In the present study, a passive acoustic monitoring station was deployed in an East Asian finless porpoise habitat in Laizhou Bay to investigate potential relationships between East Asian finless porpoises and their prey. The data revealed that porpoises were acoustically present nearly every day during the survey period. Porpoise detection rates differed between spring and autumn in concert with activities of fish choruses. During spring, fish choruses were present throughout the afternoon, and this was the time when porpoise vocalizations were the most frequently detected. During autumn, when fish choruses were absent, porpoise detection rates decreased, and diurnal patterns were not detected. The close association between fish choruses and finless porpoise activities implies an ‘eavesdropping’ feeding strategy to maximize energetic gains, similar to other toothed cetaceans that are known to engage similar feeding strategies. Underwater noise pollution, particularly those masking fish choruses, could interrupt finless porpoises’ feeding success. Fisheries competing soniferous fishes with finless porpoise could impact finless porpoise viability through ecosystem disruption, in addition to fishing gear entanglement. This article is protected by copyright. All rights reserved
... Research studying the effects of anthropogenic noise on bony fishes has shown that it can impact fishes both on an individual as well as a population level. Anthropogenic noise is harmful to marine organisms by impacting natural behaviour and can cause physical damage 23 and potentially even death, either directly or indirectly 81,82 . Anthropogenic noise affects individual fish by causing hearing loss 83,84 , inducing stress 83,85-87 , impacting immunity 88 and/or changing reproductive, social or other behaviour such as orientation 83,[89][90][91][92][93][94][95] . ...
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Cognitive abilities of sharks are well developed and comparable to teleosts and other vertebrates. Most studies exploring elasmobranch cognitive abilities have used visual stimuli, assessing a wide range of discrimination tasks, memory retention and spatial learning abilities. Some studies using acoustic stimuli in a cognitive context have been conducted, but a basic understanding of sound induced behavioural changes and the underlying mechanisms involved are still lacking. This study explored the acoustic discrimination abilities of seven juvenile grey bamboo sharks (Chiloscyllium griseum) using a Go/No-Go method, which so far had never been tested in sharks before. After this, the smallest frequency difference leading to a change in behaviour in the sharks was studied using a series of transfer tests. Our results show that grey bamboo sharks can learn a Go/No-Go task using both visual and acoustic stimuli. Transfer tests elucidated that, when both stimulus types were presented, both were used. Within the tested range of 90–210 Hz, a frequency difference of 20–30 Hz is sufficient to discriminate the two sounds, which is comparable to results previously collected for sharks and teleosts. Currently, there is still a substantial lack of knowledge concerning the acoustic abilities and sound induced behaviours of sharks while anthropogenic noise is constantly on the rise. New insights into shark sound recognition, detection and use are therefore of the utmost importance and will aid in management and conservation efforts of sharks.
... This suggests that music might not only mask unwanted background noise but also meaningful communication sounds. In wild animals, acoustic masking of meaningful sounds is thought to be one of the primary reasons why anthropogenic noise is harmful (Slabbekoorn et al., 2010). Second, direct evidence to support the acoustic masking hypothesis is rather limited, as studies do not set out to explicitly test it (it is more often invoked as a post hoc explanation of results). ...
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Music can have powerful effects on human health and wellbeing. These findings have inspired an emerging field of research that focuses on the potential of music for animal welfare, with most studies investigating whether music can enhance overall wellbeing. However, this sole focus on discovering what effects music have on animals is insufficient for advancing scientific and practical understanding of how music can be used as an enrichment tool and can also lead to problems in experimental design and interpretation. This paper argues for a different approach to the study of music for welfare, where music is used to address specific welfare goals, taking account what animals hear in music and selecting or creating ‘musical’ compositions that test current hypotheses about how music is able to influence animal behaviour and physiology. Within this conceptual framework, we outline the process through which perceptual abilities influence welfare outcomes and suggest reframing music for welfare research as Auditory Enrichment Research which adopts a targeted approach that does not purpose music as an all-round welfare enhancer but rather investigates whether auditory enrichment can ameliorate specific welfare problems based on species-specific perceptual abilities, needs, and welfare goals. Ultimately, we hope that these discussions will help to bring greater unification, vision, and directionality in the field.
... Anthropogenic noise levels have drastically increased over the past century (Slabbekoorn et al. 2010;Ortega 2012). In the continental USA, background sound levels have doubled in nearly two-thirds of all protected areas (Buxton et al. 2017). ...
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Traffic noise is one of the leading causes of reductions in animal abundances near roads. Acoustic masking of conspecific signals and adventitious cues is one mechanism that likely causes animals to abandon loud areas. However, masking effects can be difficult to document in situ and the effects of infrequent noise events may be impractical to study. Here, we present the Soundscapes model, a stochastic individual-based model that dynamically models the listening areas of animals searching for acoustic resources (“searchers"). The model also studies the masking effects of noise for human detections of the searchers. The model is set in a landscape adjacent to a road. Noise produced by vehicles traveling on that road is represented by calibrated spectra that vary with speed. Noise propagation is implemented using ISO-9613 procedures. We present demonstration simulations that quantify declines in searcher efficiency and human detection of searchers at relatively low traffic volumes, fewer than 50 vehicles per hour. Traffic noise is pervasive, and the Soundscapes model offers an extensible tool to study the effects of noise on bioacoustics monitoring, point-count surveys, the restorative value of natural soundscapes, and auditory performance in an ecological context.
... The reason to understand underwater sound is that sounds and vibrations provide a great deal of important information to animals about their environment, potential mates, competitors, predators, and prey, just as sound in air is critical for the lives of all terrestrial animals (e.g., Fay and Popper, 2000;Slabbekoorn et al., 2010;Hawkins and Popper, 2018;Slabbekoorn, 2018). Indeed, sound is an essential communication channel for aquatic vertebrates and many aquatic invertebrates (reviewed in Hawkins et al., 2015;. ...
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There are substantial knowledge gaps regarding both the bioacoustics and the responses of animals to sounds associated with pre-construction, construction, and operations of offshore wind (OSW) energy development. A workgroup of the 2020 State of the Science Workshop on Wildlife and Offshore Wind Energy recommended priority studies for the next five years to help stakeholders better understand potential cumulative biological impacts of sound and vibration to fishes and aquatic invertebrates as the OSW industry develops. The workgroup identified seven short-term priorities that include a mix of primary research and coordination efforts. Key research needs include the examination of animal displacement and other behavioral responses to sound, as well as hearing sensitivity studies related to particle motion, substrate vibration, and sound pressure. Other needs include: identification of priority taxa on which to focus research; standardization of methods; development of a long-term highly instrumented field site; and examination of sound mitigation options for fishes and aquatic invertebrates. Effective assessment of potential cumulative impacts of sound and vibration on fishes and aquatic invertebrates is currently precluded by these and other knowledge gaps. Filling critical gaps in knowledge will improve our understanding of possible sound-related impacts of OSW energy development to populations and ecosystems.
... Small boat noise may have potential negative effects on marine species that depend on these habitats to forage, breed and/or rest; these effects include hearing threshold shifts and masking of communication in fishes, stress-related physiological responses and behavioural modification (Slabbekoorn et al., 2010). At the behavioural level, boat noise exposure causes alteration of the schooling behaviour, reduction in territorial defence and decrease in feeding frequency, corresponding to changes of physiological conditions; further exposure to boat noise is also related to a reduction in the spawning activity of fish species and a decrease of the anti-predator response, enhancing in its turn the individual predation risk (reviewed by Di Franco et al., 2020). ...
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The brown meagre (Sciaena umbra) is a vulnerable vocal fish species that may be affected by boat noise. The breeding site distribution along the anthropized Venice sea inlets was investigated, by using the species' chorusing activity as a proxy of spawning. Passive acoustic campaigns were repeated at 40 listening points distributed within the three inlets during three-time windows in both summer 2019 and 2020. The role of temporal, morphological, and hydrodynamic variables explaining the observed distribution patterns was evaluated using a GLM approach, considering also human-induced pressures among the candidate predictors. The GLM analysis indicates a higher probability of recording S. umbra chorus after sunset in deeper areas of the inlets, characterized by low water current, while the underwater noise overlapping the species' hearing range and boat abundance did not play any role. This suggests that the species' breeding site choice in the inlets was not influences by boat-induced pressure.
... Behavioral changes associated with airborne and water-borne acoustic noise pollution have been well documented (Slabbekoorn and Peet 2003;Foote et al. 2004;Miksis-Olds and Wagner 2011;Orci et al. 2016) and reviewed in Barber et al. (2010) and Shannon et al. (2016). It appears that many animals are still able to survive and reproduce in acoustic noise, though the required behavioral changes could lead to reduced fitness, altered community composition, and consequently altered ecological processes (Habib et al. 2007;Francis et al. 2009;Slabbekoorn et al. 2010;Francis and Barber 2013;Read et al. 2013;Bunkley et al. 2017). ...
... Attempts to gain an understanding about the effects of anthropogenic noise on fish have been growing in the past decade. Noise can impact fishes by changes in the anatomy, physiology and/or behaviour (Slabbekoorn et al., 2010;Kunc et al., 2016;Kuşku et al., 2018). It is linked to damages to the ears and/or swim bladder Breitzler et al., 2020), changes in hearing abilities (by increasing the auditory threshold level, Scholik and Yan, 2001, and/or due to masking, Alves et al., 2021), increased stress response (secretion of cortisol - Wysocki et al., 2006;ventilation rate -Kusku, 2020;Kusku et al., 2020), increased metabolic costs (Buscaino et al., 2010), decreased growth performance , reduced foraging performance (Purser and Radford, 2011), increased risk of predation (Voellmy et al., 2014), and changes in reproduction (de Jong et al., 2020). ...
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Marine traffic is the most common and chronic source of ocean noise pollution. Despite the evidence of detrimental effects of noise exposure on fish, knowledge about the effects on the critical early life stages - embryos and larvae - is still scarce. Here, we take a natural habitat-based approach to examine potential impacts of boat noise exposure in early life stages in a wild fish population of the Lusitanian toadfish (Halobatrachus didactylus). In-situ experiments were carried out in the Tagus estuary, an estuary with significant commercial and recreational boat traffic. Nests with eggs were exposed to either ambient (control) or boat noise (treatment), for 1 fortnight. Eggs were photographed before being assigned to each treatment, and after exposure, to count number of eggs and/or larvae to assess survival, and sampled to study development and oxidative stress and energy metabolism-related biomarkers. Data concerns 4 sampling periods (fortnights) from 2 years. Results indicate that offspring survival did not differ between treatments, but boat-noise induced a detrimental effect on embryos and larvae stress response, and on larvae development. Embryos showed reduced levels of electron transport system (ETS), an energy metabolism-related biomarker, while larvae showed higher overall stress responses, with increased levels of superoxide dismutase (SOD), DNA damage (antioxidant responses) and ETS, and reduced growth. With this study, we provided the first evidence of detrimental effects of boat noise exposure on fish development in the field and on stress biomarker responses. If these critical early stages are not able to compensate and/or acclimate to the noise stress later in the ontogeny, then anthropogenic noise has the potential to severely affect this and likely other marine fishes, with further consequences for populations resilience and dynamics.
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Sound Pressure Levels were recorded using an Automated Noise Measurement System, during July 2015 - April 2016 at the Kongsfjorden, Arctic. The fjord houses the NyAlesund port and has many vessels plying during summer, which contributes to anthropogenic noise. Spectral distribution and average sound level at 1/3-octave band from 63 Hz to 5000 Hz has been analyzed and correlated with Automatic Identification System marine traffic data. The radiated acoustic field from vessel transits has been predicted through source level modeling for different category vessels. Further, an acoustic propagation model MMPE based on Parabolic Equation method has been used to evaluate range dependent propagation along the fjord and Transmission Loss estimates have been calculated for upslope and down slope cases. Noise due to shipping has been estimated using Source-Path-Receiver Model using Propagation Loss model estimates, Sound Pressure Level, and Source Level predictions. Noise maps with level contours are generated for shipping, depicting the maximum sound levels for the Kongsfjorden.
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Applications of underwater acoustics include sonar, communication, geophysical imaging, acoustical oceanography, and bioacoustics. Specialists typically work with little interdisciplinary interaction, and the terminology they employ has evolved separately in each discipline, to the point that transdisciplinary misunderstandings are common. Furthermore, increasing societal concern about possible detrimental effects of underwater noise on aquatic animals has led national and international regulators to require monitoring of underwater noise, with a consequent need for interdisciplinary harmonization of terminology. By adopting a common language, we facilitate the effective communication of concepts and information in underwater acoustics, whether for research, technology, or regulation. In the words of William H. Taft, “Don't write so that you can be understood, write so that you can't be misunderstood.” Clear definitions of widely used terms are needed, such as those used for the characterization of sound fields (e.g., “soundscape” and “ambient noise”), sound sources (“source level” and “source waveform”), sound propagation (“transmission loss” and “propagation loss”), and sound reception (“hearing threshold” and “frequency weighting function”). Terms that are used synonymously in one application have different meanings in another (examples include “hearing threshold” versus “detection threshold” and “transmission loss” versus “propagation loss”). Distinct definitions for these and many other acoustic terms are provided in a standard published in April 2017 by the International Organization for Standardization, ISO 18405. This article summarizes ISO 18405 and the process that led to the published definitions, including the reasons for omitting some terms.
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The characteristics of traditional fishing boats based on distance are very important to be studied as the main contributor to noise pollution in Cilacap waters. Therefore, this study aimed to determine noise intensity and frequency based on the distance for each traditional fishing boat (3, 5, and 10 Gross Tonage/GT). The results showed that these boats emitted noise with broadband frequency and peak receive levels of 137.6 dB re 1 μPa (3 GT fishing boat at 42.6 m). Furthermore, the noise characteristics were different for each type of ship due to differences in size, engine type, and operational speed. The receive level had the same decreased pattern based on the distance for each noise frequency but with a different intensity. Meanwhile, the noise frequency increased linearly based on the distance and was directly proportional to the pattern of change. Therefore, the higher the frequency, the faster the disappearance of the intensity with increasing distance.
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The increase in urbanization and the progressive development of marine industries have led to the appearance of a new kind of pollution called “noise pollution”. This pollution exerts an increasing pressure on marine mammals, fish species, and invertebrates, which constitutes a new debate that must be controlled in a sustainable way by environmental and noise approaches with the objective of preserving marine and human life. Despite, noise pollution can travel long distances underwater, cover large areas, and have secondary effects on marine animals; by masking their ability to hear their prey or predators, finding their way, or connecting group members. During the COVID-19 pandemic, except for the transportation of essential goods and emergency services, all the public transport services were suspended including aircraft and ships. This lockdown has impacted positively on the marine environment through reduction of the noise sources. In this article, we are interested in noise pollution in general, its sources, impacts, and the management and future actions to follow. And since this pollution is not studied in Morocco, we focused on the different sources that can generate it on the Moroccan coasts. This is the first review article, which focuses on the impact of the COVID 19 pandemic on this type of pollution in the marine environment; which we aim to identify the impact of this pandemic on underwater noise and marine species. Finally, and given the increase in noise levels, preventive management, both at the national and international level, is required before irreversible damage is caused to biodiversity and the marine ecosystem.
Preprint
Anthropogenic sound is currently recognized as a source of environmental pollution in terrestrial and aquatic habitats. Elevated sound levels may cause a broad range of impacts on aquatic organisms among taxa. Sound is an important sensory stimulus for aquatic organisms and it may cause fluctuations in stress-related physiological indices and in a broader extent induce behavioural effects such as driving as a distracting stimulus, masking important relevant acoustic signals and cues in a range of marine and freshwater species. However, sound exposure may also induce changes in swimming activities, feed efficiency and productivity of available food sources in fish. Here, we tested sound effects on swimming activities and foraging performance in thirty adult Zebrafish (Danio rerio) individually in captivity. We used four sound treatments with different temporal patterns (all in the same frequency range and moderate exposure level). Our results revealed clear sound-related effects on zebrafish behaviour. All sound treatments induced a significant increase in the number of startle response, brief and prolonged swimming speed for zebrafish (P<0.05). Zebrafish reached to the baseline swimming speed after 60 seconds in all treatments. We found partially brief and prolonged sound effects on spatial distribution of zebrafish; Although we did not find any significant sound-related behavioural changes for horizontal spatial displacement in all treatments (P>0.05), zebrafish swam significantly more in the lower layer of the fish tank except irregular intermittent 1:1-7 in brief sound exposure (P<0.05). The results of foraging performance showed that food discrimination error was low for the zebrafish and unaffected by sound treatments (P>0.05). However, food handling error was affected by sound treatments; all treatments caused a rise in handling error (P<0.001). This study highlights the impact of sound on zebrafish swimming activities, and that more attacks are needed to consume the same number of prey items under noisy conditions.
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First book dedicated to Biodiversity Beyond National Jurisdiction gathering a diverse crowd of authors from various backgrounds and professions. This book was conceived as a guide book for delegations before the start of the negotiations. It highlights many issues including governance, sustainable management, conservation on the seabed, conservation in the water column, marine pollution, sustainable use of biodiversity and marine genetic resources , polar zones, benefit sharing & dispute settlements.
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Anthropogenic noise is increasing at an alarming rate in urban as well as rural ecosystems and detrimental effects have been reported on many animals relying on acoustic communication. Little is known regarding the impact of different types of noise on community level predator perception and breeding behaviour. Here, we presented a predator model alone or a predator combined with a specific noise type, such as traffic, a lawnmower or a chainsaw, to breeding pairs of great tits, Parus major, giving them the opportunity to perform mobbing behaviour that could provide public information to their neighbours. We then measured the provisioning behaviour of adjacent tit pairs, which were 50–150 m away from the focal pairs' nests. The adjacent breeding pairs decreased nest visits when focal birds were exposed to the sparrowhawk model or to the sparrowhawk model combined with the lawnmower noise. Neighbouring pairs did not reduce the rate of nest visits when focal birds were exposed to the hawk model combined with the traffic or the chainsaw noise. The distance from focal nests did not alter the noise effect on neighbouring pairs. We suggest that auditory masking is the most likely mechanism to explain why noise compromises public information. The chainsaw and traffic noise overlap with the frequency of mobbing calls and disrupt the transmission of auditory signals in the community. Further, when the hawk presentation was combined with the chainsaw noise, which was the type of noise that had the highest frequencies, the latency of mobbing by the focal birds was strongly increased, and the number of species involved in mobbing was reduced. This study demonstrates that the signalling function of mobbing is ineffective in noisy environments which ultimately impacts fitness via increased predation to adults or their offspring.
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Male frogs call to attract females for mating and to defend territories from rival males. Female frogs of some species prefer lower-pitched calls, which indicate larger, more experienced males. Acoustic interference occurs when background noise reduces the active distance or the distance over which an acoustic signal can be detected. Birds are known to call at a higher pitch or frequency in urban noise, decreasing acoustic interference from low-frequency noise. Using Bayesian linear regression, we investigated the effect of traffic noise on the pitch of advertisement calls in two species of frogs, the southern brown tree frog (Litoria ewingii) and the common eastern froglet (Crinia signifera). We found evidence that L. ewingii calls at a higher pitch in traffic noise, with an average increase in dominant frequency of 4.1 Hz/dB of traffic noise, and a total effect size of 123 Hz. This frequency shift is smaller than that observed in birds, but is still large enough to be detected by conspecific frogs and confer a significant benefit to the caller. Mathematical modelling predicted a 24% increase in the active distance of a L. ewingii call in traffic noise with a frequency shift of this size. Crinia signifera may also call at a higher pitch in traffic noise, but more data are required to be confident of this effect. Because frog calls are innate rather than learned, the frequency shift demonstrated by L. ewingii may represent an evolutionary adaptation to noisy conditions. The phenomenon of frogs calling at a higher pitch in traffic noise could therefore constitute an intriguing trade-off between audibility and attractiveness to potential mates.
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The basic information on the structure and function of the auditory system in fishes is presented. The anatomy and morphology of otolith organs, principles of their function as the detectors of accelerations, mechanisms of the direct and indirect effects of a sound wave on the auditory receptors, as well as the structure of various accessory auditory organs (the Weberian apparatus, tympanic bladder, suprabranchial chamber, lateral trunk channels, and swimbladder protrusions) and their role in the increase of hearing capabilities are described. The data on the functional possibilities of the auditory system in fish (sound spectrums, absolute and discriminating auditory sensitivities, and sensitivities to ultrasound and infrasound) are analyzed. A comprehensive information on directional hearing in fish is discussed. The possible mechanisms and hypotheses describing the ability of fish to determine the direction to a sound source are reported. The contradictions in the present opinions on a role of the swimbladder in sound reception of the fishes belonging to the group of hearing generalists are specified. The similarities and differences in signal reception between the auditory organ and lateral line are analyzed. Development of the main structures of the auditory system, as well as the appearance of hearing ability in the ontogeny are followed. A role of hearing in behavior of fish is briefly reviewed. Lack of knowledge on many aspects of hearing function in fishes is noted.
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This paper reviews the application of several sensory signals for their possible use in the control and modification of fish behavior but emphasizes the use of sound. Basic principles of underwater acoustics are introduced, followed by an overview of the structures and function of the fish ear and lateral line. Sounds in the sonic, infrasonic, and ultrasonic ranges are potentially useful for controlling fish behavior. However, most experiments testing the usefulness of such sounds have given ambiguous results except when ultrasound has been used to control some clupeid species. Very little is known about the potential usefulness of chemical and electric signals (other than electric shocks) for behavioral control. A substantial literature on the use of light to attract or repel fish offers encouraging possibilities for this control medium in some circumstances. We conclude that too little is actually known about the suitability of various signals for control of fish behavior. Many variables, such as time of day and age of the fish, affect the effectiveness even of signals that seem to “work.” These variables can influence the success or failure of a technique and need to be considered in the evaluation of any stimulus considered for the control fish behavior. Moreover, it is increasingly apparent that flow field has a powerful effect on the local success of one stimulus or another. We suggest that sound and light be further explored for control of fish behavior, particularly in combination. This work cannot be done with only field studies or only laboratory studies or by only applied biologists or only basic scientists; all methods and expertise are needed. Finally, no behavioral control method will work unless the behavior of the subject species is thoroughly understood in each place of application.
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The reaction of fish induced by a trawling vessel was measured using the Bergen Acoustic Buoy. It is a free-floating buoy with a split beam echo sounder system. Individual fish trajectories were obtained by target tracking methods, and average swimming velocities as a function of depth and time before and after passage of the vessel was calculated. A measure for the change in behaviour was applied, showing a significant response during and after propeller passage. The change in horizontal displacement speed is significant at all depths, while the change in vertical displacement velocity is significant at all but one layer of depth. The horizontal reaction seems to occur a bit later than the diving reaction. After the main response, a slightly higher mean horizontal displacement speed was observed for the deepest layers. This indicates a change in the fish state after being exposed to the vessel/gear.
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The current knowledge on detection of, and reaction to, sound by fish is reviewed, with special emphasis on underwater noise from offshore wind farms. The detection distance to wind farms for 3 species of fish representing various hearing capabilities varies between 0.4 and 25 km at wind speeds of 8 to 13 m s -1. The detection distance depends on the size and number of windmills, the hearing abilities of the fish, background noise level, wind speed, water depth and type of sea bottom. The noise from windmills may decrease the effective range for sound communication of fish; however, it is not known to what extent this decrease affects the behaviour and fitness of fish. Windmill noise does not have any destructive effects upon the hearing abilities of fish, even within distances of a few metres. It is estimated that fish are consistently scared away from windmills only at ranges shorter than about 4 m, and only at high wind speeds (higher than 13 m s -1). Thus, the acoustic impact of windmills on fish is restricted to masking communication and orientation signals rather than causing physiological damage or consistent avoidance reactions. These conclusions must be viewed with great caution, however, as the existing data are prone to large uncertainties. Further studies on more detailed measurements of the sound-field and of fish behaviour around windmills are needed.
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Jinn-Pyng Ueng, Bao-Quey Huang, and Hin-Kiu Mok (2007) Sexual differences in the spawning sounds of the Japanese croaker, Argyrosomus japonicus (Sciaenidae). Zoological Studies 46(1): xxx-xxx. Sexual differences in the calls voluntarily emitted during the spawning season of the Japanese croaker (Argyrosomus japonicus) raised in tanks and ponds in the Penghu Archipelago, Taiwan, are described. Calls are composed of a train of pulses of drumming sounds and were heard primarily after dusk. The spawning-season advertisement calls of the male and female differ; females generated significantly more pulses per call, and their calls had a longer call duration, a shorter pulse period, and a lower dominant frequency than those of
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Gravid females of Alytes obstricans and Alytes cisternasii were tested with synthetic calls in seven-speaker playback tests. A first, “mean-centered” test presented calls with frequencies representing an array of different calls spanning over the range of the population (±2.25 SD). In this test, females of both species approached a synthetic call that was lower than the average call frequency of the male population although the difference was significant only for A. obstetricans. The regression between female weight and size and preferred frequency was not significant in either species. These results confirm the reported trends of females preferring lower frequency calls (corresponding to larger males) based on two-speaker playback tests for A. obstetricans. For A. cisternasii, the lack of significance of the seven-speaker test suggests that the preference trend previously found in two-speaker tests may be obscured in more complex acoustical environments. A second “supernormal stimulus” test presented females with calls ranging from the lowest frequency values of the male population (−2.25 SD) and lower, up to −6.75 SD beyond the range. In both species females preferentially approached calls higher than the mean frequency of the stimulus presented. This result suggests that in both cases selection for low frequencies is not open ended, and that the preferred frequency is within the range of the male population.
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The effect of boat noise on the behaviour of bluefin tuna Thunnus thynnus was investi- gated in the Egadi Islands, Sicily, during spring 2005 using a fixed tuna trap set near shipping routes. Tuna behaviour was observed when exposed to both natural ambient sound and sound generated by hydrofoil passenger ferries, small boats and large car ferries. Acoustical and behavioural analyses were conducted with and without extraneous sound to define a list of behavioural categories. Each vessel produced different engine sounds with regard to their composition and bandwidth, and all were distinctly different from ambient sound levels. In the absence of boat noise, tuna assumed a con- centrated coordinated school structure with unidirectional swimming and without a precise shape. When a car ferry approached, tuna changed swimming direction and increased their vertical move- ment toward surface or bottom; the school exhibited an unconcentrated structure and uncoordinated swimming behaviour. Hydrofoils appeared to elicit a similar response, but for shorter periods. Ago- nistic behaviour was more evident when exposed to sounds from outboard motors of small boats. This study showed that local noise pollution generated by boats produced behavioural deviations in tuna schools. Schooling enhances tuna homing accuracy during their spawning migration, and an alter- ation in schooling behaviour can affect the accuracy of their migration to spawning and feeding grounds.
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We tested the hypothesis that reproductive success is randomly distributed within spawning aggregations of Atlantic cod Gadus morhua, a broadcast-spawning marine fish for which no parental care is provided. Based on microsatellite DNA-parentage assignment of 8913 offspring from 4 large (n = 52 to 93) experimental spawning aggregations, we quantified individual variation in male reproductive success and evaluated the degree to which this variation could be explained by aspects of morphology, condition, and spawning behaviour. Reproductive success was highly skewed, with more than 80% of the offspring within each group sired by 2 to 7 individuals. Body size and agonistic interactions initiated were positively associated with male reproductive success within each group. The lengths of fins prominent during courtship and mating were also correlated with reproductive success within one of the spawning groups for which data were available. Our observations are consistent with the hypotheses that some form of intrasexual competition or mate choice is a constituent of the mating system of this species and that the ratio of effective to census population size in broadcast-spawning marine fishes is very small.
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Anthropogenic sound in the marine environment continues to increase. Sound sources range from increased vessel traffic to transient but intense sounds such as those produced by seismic air guns, pile driving, or some sonars. While most interest in anthropogenic sounds has focused on marine mammals, there is an increasing concern regarding the impact of such sounds on fishes and marine invertebrates. Since the inner ear hearing receptors of fishes are similar to those of marine mammals, any effects seen on the hearing receptors of marine mammals may also be found in fishes and vice versa. Despite increasing interest in the effects of sounds on fishes, this issue has only been addressed on the most limited scale. Here we review the current literature in this area. It has been reported that high sound levels can damage the inner ear sensory cells, produce hearing loss (threshold shifts), elicit stress responses, and alter the behavior of fishes. At least in terms of hearing loss, these effects are modulated by exposure sound level and duration. The effects of various types of sound (e.g., impulsive vs. continuous) and long-term impacts of how anthropogenic sounds affect the behavior and ecology of fishes need exploration in the future.
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Many species of fish use auditory cues as part of their reproductive repertoire but intended receivers must be able to localize sounds to make full use of this information. Specialized couplings between the ear and swim bladder are thought to be critical for acoustic localization, yet species without specialized connections use acoustic cues in reproductive displays. In an attempt to better understand mechanisms of acoustic localization, we used the round goby (Neogobius melanostomus), a hearing generalist, to assess responses to calls in the lab and field. The call used for playback was recorded in the field from an actively displaying male round goby and consisted of a series of low frequency pulses. In the field, playback of the call resulted in a significant enhancement of approaches toward, and entries into, an experimental arena as compared to when the sound was off. There was no effect on the amount of time spent near the speaker however. In the lab, males and females responded actively when calls were played and females showed a significant attraction to the playing speaker. Responses were highly directional with little angular deviation, suggesting true localization to the sound source. While the sensory mechanisms allowing round gobies to selectively respond to conspecific vocalizations remain unknown, it is clear that they do show highly directional responses to acoustic cues in both laboratory and field settings.
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Ocean ambient sound data from 1994 to 2001 have been collected using a receiver on the continental slope off Point Sur, California. A tempo-rary, nearby receiving array was used for calibration purposes. The resulting data set is compared with long-term averages of earlier measurements made with the identical receiver over the period from 1963 to 1965. This compar-ison shows that the 1994 to 2001 levels exceed the 1963 to 1965 levels by about 10 dB between 20 and 80 Hz and between 200 and 300 Hz, and about 3 dB at 100 Hz. Increases in (distant) shipping sound levels may account for this.
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Spawning site selection by spotted seatrout and black drum was studied by locating drumming aggregations through the use of a hydrophone. From March 1987 to October 1990, 315 sound observations were made to identify and characterize spawning seasons and environmental requirements of both species in the Barataria, Caminada, and eastern Timbalier Bay systems of Louisiana. The sounds produced by the spawning aggregations were identified and verified against known recordings. Spawning was verified on several occasions by capturing and rearing zygotes (eggs) into identifiable larvae. Spotted seatrout formed drumming aggregations from late May to early October at salinities ranging from 7.0 to 25.8 ppt and temperatures from 24.5 to 33.5 C. Black drum formed drumming aggregations between January and April in salinities from 10.0 to 27.0 ppt and temperatures from 15.0 to 24.0C. Large drumming aggregations of spotted seatrout were located from 1800 to 2400h and from 1800 to 2200h for black drum. Spotted seatrout aggregation size was highly correlated with water temperature and for black drum with dissolved oxygen concentrations. Spawning sites for both species were frequently located in deep moving water between barrier islands as well as in channels in open water where water depth ranged from 3 to 50 m. Spawning site selection depended on a particular range of environmental conditions and spawning locations varied seasonally and yearly depending upon hydrological variation.
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Acoustic communication is critical for reproductive success in the oyster toadfish Opsanus tau. While previous studies have examined the acoustic characteristics, behavioral context, geographical variation, and seasonality of advertisement boatwhistle sound production, there is limited information on the grunt or other non-advertisement vocalizations in this species. This study continuously monitored sound production in toadfish maintained in an outdoor habitat for four months to identify and characterize grunt vocalizations, compare them with boatwhistles, and test for relationships between the incidence of grunt vocalizations, sound characteristics and environmental parameters. Oyster toadfish produced grunts in response to handling, and spontaneous single (70% of all grunts), doublet (10%), and trains of grunts (20%) throughout the May to September study period. Grunt types varied in pulse structure, duration, and frequency components, and were shorter and of lower fundamental frequency than the pulse repetition rate of boatwhistles. Higher water temperatures were correlated with a greater number of grunt emissions, higher fundamental frequencies, and shorter sound durations. The number of grunts per day was also positively correlated with daylength and maximum tidal amplitude differences (previously entrained) associated with full and new moons, thus providing the first demonstration of semilunar vocalization rhythms in the oyster toadfish. These data provide new information on the acoustic repertoire and the environmental factors correlated with sound production in the toadfish, and have important implications for seasonal acoustic communication in this model vocal fish.
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