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The improvements in marine technological developments propagate urbanization in the ocean environment. The construction or operational activities of marine structures such as energy plants, oil platforms, pipelines , sea-tunnel passages, or cable-stayed suspension bridges, and vessel traffic are sources of underwater noise pollution. How underwater sounds such as piling, pole drilling, or machinery noises may affect the marine live is mostly ignored in marine construction, and there is lack of information regarding underwater sound effects on marine live in the oceans. Recently, a remarkable interest is developing concerning underwater sound effects, especially in aquaculture facilities, with experimentation of musical stimuli or various noises caused by pumps or filter systems on behavior and stress responses of fish in culture conditions. With the increase of urbanization and progressive development of marine industries, more and more pressure from human-generated (anthropogenic) underwater sound pollution may threaten marine mammals, fish species and invertebrates from underwater noises that in terms might be called as "Underwater Noise Pol-lution". The future of marine life and that of human being, and the dramatic increase of underwater sound pollution is a new debate that needs to be controlled in a sustainable way with environment-sound approaches. Therefore the potential effects of various sound sources derived from marine industrial activities have been reviewed in this study.
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E-ISSN 2618-6365
Aquatic Rese arch 1(4), 148-161 (2018) DOI: 10.3153/AR18017
Review Article
148
ACOUSTIC NOISE POLLUTION FROM MARINE INDUSTRIAL
ACTIVITIES: EXPOSURE AND IMPACTS
Halit Kuşku1, Murat Yiğit2, Sebahattin Ergün3, Ümüt Yiğit3,
Nic Taylor4
1 Canakkale Onsekiz Mart University,
School of Applied Sciences at
Canakkale, Department of Fisheries,
17100, Canakkale, Turkey
2 Canakkale Onsekiz Mart University,
Faculty of Marine Science and
Technology, Department of Marine
Technology, 17100, Canakkale,
Turkey
3 Canakkale Onsekiz Mart University,
Faculty of Marine Science and
Technology, Department of
Aquaculture, 17100, Canakkale,
Turkey
4 SS Snow-Leopard Research Vessel,
Multihull Centre, Foss Quay,
Millbrook, Cornwall, PL10 1EN,
United Kingdom, UK
Submitted: 02.07.2018
Accepted: 09.08.2018
Published online: 10.08.2018
Correspondence:
Murat YİĞİT
E-mail: muratyigit@comu.edu.tr
©Copyright 2018 by ScientificWebJournals
Available online at
http://aquatres.scientificwebjournals.com
ABSTRACT
The improvements in marine technological developments propagate urbanization in the ocean en-
vironment. The construction or operational activities of marine structures such as energy plants,
oil platforms, pipe-lines, sea-tunnel passages, or cable-stayed suspension bridges, and vessel traf-
fic are sources of underwater noise pollution. How underwater sounds such as piling, pole drilling,
or machinery noises may affect the marine live is mostly ignored in marine construction, and there
is lack of information regarding underwater sound effects on marine live in the oceans. Recently,
a remarkable interest is developing concerning underwater sound effects, especially in aquaculture
facilities, with experimentation of musical stimuli or various noises caused by pumps or filter sys-
tems on behavior and stress responses of fish in culture conditions. With the increase of urbaniza-
tion and progressive development of marine industries, more and more pressure from human-gen-
erated (anthropogenic) underwater sound pollution may threaten marine mammals, fish species
and invertebrates from underwater noises that in terms might be called as “Underwater Noise Pol-
lution”. The future of marine life and that of human being, and the dramatic increase of underwater
sound pollution is a new debate that needs to be controlled in a sustainable way with environment-
sound approaches. Therefore the potential effects of various sound sources derived from marine
industrial activities have been reviewed in this study.
Keywords: Marine industry, Underwater sound, Noise pollution, Anthropogenic noise, Fish be-
havior
Cite this article as:
Kuşku, H., Yiğit, M., Ergün, S., Yiğit, Ü., Taylor, N. (2018). Acoustic Noise Pollution from Marine Industrial Activities: Exposure and Impacts.
Aquatic Research, 1(4), 148-161. DOI: 10.3153/AR18017
Aquatic Rese arch 1(4), 148-161 (2018) DOI: 10.3153/AR18017
Review Article
r
Introduction
Acoustic noise pollution generated by marine industrial ac-
tivities such as the construction of wind energy plants, oil or
gas explorations, cable-stayed suspension bridge, sea-tun-
nel passage etc. has been increasing in the oceans around the
world. The rapid increase of industrialization introduces
more and more anthropogenic sounds such as pile driving,
pole drilling, dredging, or trenching during the construction
works in the marine environment. Not only marine mam-
mals but also a variety of marine living animals is under
thread of noise pollution (Popper & Hawkins 2012). There
are several reports on sounds affecting marine mammals
(Andrew et al., 2002; Southall et al., 2007), however still
many questions remain regarding the hearing capabilities,
stress or sound-responses of fish (Kusku et al., 2018) and
invertebrates (André et al., 2011), and understanding the po-
tentials of human-made acoustic noise pollution in marine
environment. Further, underwater noises from international
vessels traffic or coastal fishermen’s boats are further
sources of acoustic noise to consider. The effects of the ship-
ping industry or recreational boat noises on fish behavior are
reported in limited documents related to population assess-
ment or fisheries management, indicating that acoustic
noises by ships might influence fish behavior and welfare of
fish.
Fish in mass production conditions are often exposed to
stress, and is an important criterion for fish welfare, and an
important consideration for the assessment of best practice
in aquaculture facilities. The most regularly encountered
stress conditions such as irregularities in water temperature
(Hsieh et al., 2003); fish stocking and hierarchy of domi-
nance (Clement et al., 2005; Gilmour et al., 2005), colora-
tion in culture tanks (Kesbiç et al., 2016), photoperiod re-
gimes (Ergün et al., 2003), or fish transport, handling and
husbandry (Kayali et al., 2011), have had limited studies
performed to evaluate the effect of such stresses in aquacul-
ture conditions.
Mass production in intensive culture conditions may lead to
reduced fish welfare because of a stressful environment that
in terms might affect fish health (Hoseinifar et al., 2017;
Yousefi et al., 2012). Earlier studies revealed that fish ex-
posed to stressful conditions may alter their physiological
conditions such as haematological parameters, which are
important criteria for the determination of stress, disease and
organ health status in fish (Yilmaz et al., 2013; Yilmaz et
al., 2018a,b). Also Barton et al. (1988) reported that blood
plasma cortisol and glucose levels are useful indicators for
primary or secondary stress conditions in fishes. In goldfish
exposed to short-term underwater white noise transmission
with a bandwidth ranging from 0.1 to 10 kHz at 160170 dB
re 1 μPa SPL, plasma cortisol levels were significantly af-
fected by the noise exposure, which was not the case for
plasma glucose levels (Smith et al., 2004). The authors
found that especially mean cortisol levels tripled over the
controls after 10 min of noise exposure and thereafter de-
clined back to control levels after 60 min of exposure period.
In the long-term noise exposure tests however, the authors
underlined that noise exposure did not significantly affect
cortisol or glucose concentrations, likely an indication of
stress recovery in the long exposure period. Even though,
haematological and physiological response parameters
could be useful indicators of stress conditions in fish ex-
posed to acoustic noise pollution generated by marine indus-
trial activities. However, there is lack of information regard-
ing haematological and physiological responses in marine
animals exposed to stressors of marine industrial noise
sources, hence these types of investigations are encouraged
in future studies. Furthermore, effects of sounds generated
by pumps or filter systems in intensive production such as
recirculating aquaculture systems (RAS) are mostly disre-
garded, and is likely to affect fish welfare and behavior as a
response to stressors from noise (Galhardo & Oliveira,
2009).
Studies on anthropogenic noise effects on marine life are of
increasing interest recently (Popper, 2003), and is reported
to cause inconsistencies of behavior or habitat selection of
marine animals in the natural environment (Popper, 2003;
Tolimieri et al., 2002). Further, earlier studies Scholik &
Yan (2001) and Smith et al. (2004) reported that human-
made underwater sound can cause stress and reduce fish
welfare (Wysocki et al., 2006). In our recent study (Kusku
et al., 2018) we noticed that underwater transmitted sounds
such as urban noise may effect fish growth and cause incon-
sistencies of fish behavior, whereas underwater transmitted
musical stimuli was reported to affect fish growth and wel-
fare in a positive manner in common carp (Papoutsoglou et
al., 2007; Papoutsoglou et al., 2010), in gilthead sea bream
(Papoutsoglou et al., 2008), in turbot (Catli et al., 2015), and
in koi fish (Kusku et al., 2018).
There are investigations on-going in the monitoring of the
underwater sounds made by marine mammals in the oceans
via recording their natural calls with Passive Acoustic Mon-
itoring (PAM) systems, which is also commonly used for
the detection of marine mammals (NAI, 2012). The so
called PAM system may help to gather information regard-
ing habitat selection or behavior of marine animals in their
natural environment. However, in other marine animals
such as fish or invertebrates, these systems are not currently
in use, since the PAM systems are not capable of identifying
Aquatic Rese arch 1(4), 148-161 (2018) DOI: 10.3153/AR18017
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150
or detecting the presence of fishes and invertebrates, proba-
bly due to the much lower amplitudes of their calls com-
pared to that of marine mammals (NAI, 2012). Considering
that radar or sonar systems are capable of detecting a variety
of fish species or invertebrates, the use of acoustic monitor-
ing techniques to follow their habitat selection behavior
might be feasible without causing any disturbance to their
population. The future health of our oceans depends on the
rational use and control of human-made effects on the ma-
rine environment. Therefore, intensive investigations on the
effects of various kinds of industrial sounds such as under-
water drilling, piling noises, or dredging on different fish or
invertebrate species as well as active acoustic monitoring
studies are encouraged for further investigations.
Sources of Underwater Noise Pollution
Sounds in the marine acoustic environment can be sourced
as both natural and human-generated sounds. Human-gen-
erated (anthropogenic) sounds other than natural sources
can be accepted as the main source of underwater sound pol-
lution. Anthropogenic sounds have a potential threat to ma-
rine live and are increasing drastically in recent years (An-
drew et al., 2002; Slotte et al., 2004; Tyack, 2008) with the
development of marine technologies and growth of mari-
time industrial activities. Therefore, the level of underwater
background noise is becoming a significant problem that
threatens the oceans worldwide due to the growing anthro-
pogenic activities in the oceans.
There are several types and sources of underwater noises
that might affect marine living organisms in different ways.
Pile driving activities are one such source and intensively
used in marine constructions and industrial facilities. The
effects of pile driving on marine life may vary from size of
pile to depth of pile driving. The impacts of industrial noises
and underwater sounds on marine organisms can vary based
on the metrics for describing the sounds. The type of sound
as well as description of sound metrics is necessary to estab-
lish information for regulating sound effects on marine life.
Further, the size or material used in piling and the bottom
substrate might differ in the hydraulic hammer impact nec-
essary for effective piling. Therefore, the methods for meas-
uring sound intensities and impacts of underwater sound
generated by pile driving activities are wide areas of study.
In the reduction of their environmental impacts, it might be
a positive approach to find methods which could minimize
the sound level produced during the pile driving work. Since
type and size of piles used, as well as the equipment used in
piling vary, investigation for measuring sounds the different
underwater pile driving approaches might be important for
standardization and prediction of their effects on marine life.
Further, pile driving or other sources of underwater noise
generated by marine construction industries might cause dif-
ferent levels of noise pollution. Effects of underwater sound
generations from construction works such as suspension
bridge, ports and piers, including sounds of pile driving,
dredging, vibro-densification, or other marine industrial ac-
tivities such as underwater explosions, can cover an impact
area from 100 m to 1000 m, or even more farther distances
from the main sound source (Williams et al., 2014). It is ob-
vious that there is a reduction in sound level with distance
(sound transmission loss) as also reported by Bailey et al.
(2010). Bailey et al. (2010) investigated underwater sound
transmission losses from 0.1 km (maximum broadband peak
of 205 dB re 1 μPa SPL) to 80 km, and found that these
levels of SPL were not any more distinguishable at a dis-
tance of 80 km from the sound source, possible due to a re-
duction in sound level below the background noise. Addi-
tionally, the authors reported that pile driving sound could
be detected from a distance of up to 70 km horizontal range,
and their measurements indicated that behavioral disturb-
ance in bottlenose dolphins might have occurred up to a dis-
tance of 50 km from the pile driving sound source. Hence,
recorded levels of SPL from underwater field testing and
their spectral contents at various distances from the sound
source could be evaluated by considering the hearing thresh-
olds of the target marine living organisms in accordance
with the ambient noise levels of the specific area. These data
together could help to evaluate and predict possible impacts
of the sound sources in a horizontal effect-zone.
Marine industrial activities such as pile driving and pole
hammer platform at operation for a cable-stayed suspension
bridge legs in the Strait of Canakkale are given in Photos 1
and 2. Marine industrial activities such as international
shipping lines near cage aquaculture operations and
urbanized areas and nearshore ferry lines between two in-
dustrial piers are presented in Photos 3 and 4.
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Photo 1. Pile driving platform at operation for suspension bridge construction (original)
Photo 2. Piling of poles for a suspension bridge legs in the Strait of Canakkale (original)
Photo 3. Cage Aquaculture Operations near International Shipping Lines (original)
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Photo 4. Nearshore Ferry Lines between two industrial piers (original)
Other sources of underwater sound pollution could be at-
tributed to wind energy farms or oil platforms in their con-
struction and operation, these power plants which are de-
ployed on water surface require intensive pile driving during
the construction work but also produce a variety of noises
during their day to day operation. Commonly they produce
different sound pollution spectrums than that produced by
drilling for gas explorations of offshore oil or -gas plat-
forms. Wind farms are typically deployed in relative shal-
low waters, where numerous other sources of underwater
sound pollution such as local fishermen boats, coastal ship
traffic, touristic activities of motor-boats, surf noises, seis-
mic air-guns used for geophysical studies and sonar systems
are available. Among these sources, ships are permanent un-
derwater sound sources which increase the background
sound levels.
Sound Pressure Limits, Exposures and Impacts
The SPL (sound pressure limit) was estimated around 128
dB (decibel), 1 m from the sound sources of a wind farm
(NAI, 2012). Ambient noise levels in a natural marine envi-
ronment may differ according to the environmental condi-
tions such as weather state, waves, tidal and anthropogenic
impacts of the marine site, as well as depth and bottom con-
ditions. The ambient sound level ranged between 5 and 50
dB in a natural marine environment (Wenz, 1962). SPLs of
50 to 95 dB where measured in shallow waters, 1 m above
the sediment (Lagardère, 1982). However, in this discus-
sion, the effect of these noise levels is difficult to determine
because of a lack of specific criteria for comparison.
In land-based aquaculture facilities, a significant level of
noise are generated due to water pumps, aerators, selection
or harvesting machinery, automatic feeding machinery and
also various sounds of facility management (Bart et al.,
2001). SPLs of 153 dB re 1 μPa (Bart et al., 2001), and 160
dB re 1 μPa (Clark et al., 1996) have been reported, which
are 100-110 dB higher compared to those in the natural wa-
ter environment (5-50 dB). An alarm reflex or involuntary
response of fish to un-expected underwater sound might be
induced when the average SPL is much higher than the
sound level in the background. Neo et al. (2014) reported
that an acoustic noise of 165 dB re 1 μPa SPL could be high
enough in level to start the alarm reflex of fish. However,
much more information is needed for the evaluation of un-
derwater sound effects on various marine animals with
lower or higher SPLs.
Offshore marine fish farms however provide significant
benefits due to their location off the coast, reducing visual
impacts (Byron & Costa-Pierce, 2010; Byron et al., 2011),
and conflicts with coastal zone users such as tourism (Yigit
et al., 2006; Yigit, 2007). Further, improve fish welfare
could be expected in cage farms due to better water quality
in offshore conditions (Pelegri et al., 2006) with less influ-
ence terrestrial effluents and coastal acoustic sounds. De-
spite the fact that fish in land-based farms are exposed to a
wide range of noise, fish in offshore cage systems are sub-
ject to sounds caused by machineries used for fish selection,
harvesting, or feeding, and the acoustic background noises
generated by marine shipping lines and boats.
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It is likely that un-expected acoustic noise might induce a
reaction in the Mauthner cells, which are responsible of ini-
tiating alarm reflex in fish, this was reported earlier in sea-
bass (Dicentrarchus labrax) juveniles (Spiga et al., 2017) or
koi fish (Cyprinus carpio) (Kusku et al., 2018). An involun-
tary alarm reflex is mediated by a pair of hindbrain
Mauthner neurons (Szabo et al., 2006). Physiological stress
responses in marine animals to unusual surrounding noises
generally appear as stimulation of nervous activity, increase
in metabolism, and decreased immune system. When sound
pressure levels similar or less than the background acoustic
conditions are provided by human activities, it is likely that
marine animals may not be disturbed, possible due to the
less and insufficient level of sound to trigger alarm reflex
(Spiga et al., 2017; Kusku et al., 2018).
Diminishing effects on foraging behavior in marine animals
have been recorded as a fear-response when exposed to un-
derwater noise, unusual to their natural ambient. This low-
ered feeding and increased metabolic rate lead to a reduction
in growth performance (Kusku et al., 2018). The disturbance
of voluntary feeding caused by anxiety or predator reflex of
juvenile Atlantic salmon has also been reported by Metcalfe
et al. (1987). The loss of appetite is an expected response of
physiological stress (Wendelaar Bonga, 1997), possibly
caused by the induced alarm reflex of fish exposed to under-
water noise (Kusku et al., 2018). Fish growth, feeding effi-
ciency and behavior in fish were negatively affected by un-
derwater transmission of urban noise playback at 67 dB re 1
μPa SPL compared to those held under ambient-noise play-
back of 57 dB re 1 μPa SPL (Kusku et al., 2018), also an
indication of incline in metabolic rate.
More information on behavioral responses of various ma-
rine organisms to anthropogenic underwater noise expo-
sures are presented in Table 1.
White whales (Delphinapterus leucas) are reported to pre-
sent significant increase of norepinephrine, epinephrine and
dopamine levels when exposed to high level (>100 kPa) of
sound exposure near a seismic water gun. In this study, Ro-
mano et al. (2004) recorded peak pressure levels of impulse
between 198 and 226 dB re 1 μPa peak pressure (8-200 kPa)
than those in a non-noise polluted area without sound expo-
sure or exposures of lower than 100 kPa, which could be
attributed to a possible reflection of nervous activation ef-
fect of noise exposure. The authors (Romano et al., 2004)
also reported an important increase in aldosterone and sig-
nificant decline in monocytes in bottlenose dolphins (Turi-
ops truncates), after exposure to seismic air-gun noise at
213–226 dB re 1 μPa peak pressure (44–207 kPa). A shore
crab (Carcinus maenas) was reported to require higher lev-
els of dissolved oxygen when exposed to ship-noise play-
back in a controlled environment compared to those held
under ambient-noise, showing a sign of increased metabolic
rate (Wale et al., 2013). Increased physiological activity was
also reported in white whales (D. leucas) after exposure of
underwater noise from shipping industry (Lyamin et al.,
2011).
Richardson et al. (1995) reported different typologies of
acoustic noises generated by the marine industry. An oil-gas
exploration activity might generate SPLs between 119-127
dB re 1 μPa from oil drilling, and 131-135 dB re 1 μPa from
pile driving activities. A drill vessel could generate an
acoustic noise of 174-185 dB re 1 μPa SPL, whereas seismic
air-guns could even cause higher levels of SPLs over 240
dB re 1 μPa (Richardson et al., 1995). A gross tonnage
tanker or container vessel could generate an acoustic noise
of 130-205 dB re 1 μPa SPL (Gisiner et al., 1998; Williams
et al., 2014), while less SPLs of 150-175 dB re 1 μPa are
recorded for small or medium size ships (ferry) or motor
boats in the near shore area (Richardson et al., 1995).
Anthropogenic underwater noises show differences in terms
of frequency, sound pressure level (SPL) and duration of ex-
posure. Some of the acoustic sounds generated by several
marine industrial activities have been given in Table 2.
There are evidence that hearing capabilities differ among
marine species and the influence of human-made acoustic
noises on behavior or welfare of marine animals are species
specific (Smith et al., 2004; Davidson et al., 2009; Voellmy
et al., 2014). Hence, this needs to be considered in the in-
vestigations on natural marine life as well, with the con-
sistent monitoring of sound effects on behavior and distri-
bution of the populations for a comprehensive understand-
ing of acoustic ecology and assessing potential noise im-
pacts on marine animals.
Some earlier studies have underlined that fish may attune to
environmental conditions of long-term exposures to high
levels of underwater sound pressure limits (149 dB re 1 μPa
- 160 dB re 1 μPa SPL) in aquaculture facilities (Wysocki et
al., 2007; Davidson et al., 2009). Fish could even develop
tolerance to repeated exposure to underwater sounds such as
motorboat-noise, and behavioral and physiological re-
sponses of fish decreased after a certain time, even a week
after sound exposure (Nedelec et al., 2016). Since it is al-
most impossible to discourage human beings from urbani-
zation or industrialization, it seems to be important to figure
out the “threshold limit” of sound that is acceptable by -or
less harmful to -marine living organisms.
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Table 1. Behavioral effects of human-generated acoustic noise exposures on marine animals
Species name Scientific name Human-generated Noise Impacts Reference
Atlantic salmon Salmo salar predetor risk effect disturbance of voluntary feeding Metcalfe et al., 1987
Rockfish Sebastes sp. air-gun sound induced alarm reflex Skalski et al., 1992
Sockeye salmon Oncorhynchus nerka pinger sound no reaction Gearin et al., 2000
Sturgeon Acipenser sp. pinger sound no reaction Gearin et al., 2000
Herring Clupea harengus pinger sound no reaction Culik et al., 2001
Bottlenose dolphin Tursiops truncatus experimental sound shift of hearing threshold Nachtigall et al., 2004
Lusitanian toadfish Halobatrachus didactylus ship and boat noise shift of hearing threshold Vasconcelos et al., 2007
Squid Loligo pealeii playback killer whale sound no reaction Wilson et al., 2007
European seabass Dicentrarchus labrax experimental sound induced alarm reflex Kastelein et al., 2008
European eel Anguila anguila experimental sound induced alarm reflex Kastelein et al., 2008
Pink snapper Pagrus auratus seismic air-gun damage of hearing sensory epithelia Kastelein et al., 2008
Marine mammals ship traffic noise induced anti-predatory behavior Tyack, 2008
European squid Loligo vulgaris experimental sound damage of hearing sensory epithelia André et al., 2011
Common Cuttlefish Sepia officinalis experimental sound damage of hearing sensory epithelia André et al., 2011
Common octopus Octopus vulgaris experimental sound damage of hearing sensory epithelia André et al., 2011
Ommastrephid squid Illex coindetii experimental sound damage of hearing sensory epithelia André et al., 2011
Shore crab Carcinus maenas ship and boat noise loss of defense capability Wale et al., 2013
European seabass Dicentrarchus labrax experimental sound induced alarm reflex Spiga et al., 2017
Koi fish Cyprinus carpio experimental sound induced alarm reflex Kusku et al., 2018
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Table 2. Sound pressure levels (SPL) of human-generated acoustic noise exposures in marine environment
Human-generated Acoustic Noise Sound Pressure Limit (SPL) Reference
(from highest to lowest range)
Seismic air-guns 240-250 dB re 1 μPa Richardson et al., 1995
Seismic air-guns 195-210 dB re 1 μPa Wardle et al., 2001
Seismic air-guns 186-191 dB re 1 μPa Skalsky et al., 1992
Drill vessel 174-185 dB re 1 μPa Richardson et al., 1995
Ship noise (dynamic sea conditions) 173-185 dB re 1 μPa Chen et al., 2017
Piling noise 164 dB re 1 μPa Spiga et al., 2017
Small or medium size vessels (ferry & motorboat) 150-180 dB re 1 μPa Richardson et al., 1995
Ship noise (engine exhausts, in port) 135-142 dB re 1 μPa EPA, 2010
Pile driving, pole hammer 131-135 dB re 1 μPa Richardson et al., 1995
Ship noise (Marine tanker or container vessel) 130-205 dB re 1 μPa Gisiner et al., 1998; Williams et al., 2014
Ship noise (cruise line) 130 dB re 1 μPa Williams et al., 2014
Oil-gas drilling exploration 119-127 dB re 1 μPa Richardson et al., 1995
Research boat (whale-watching) 108–116 dB re 1 μPa Williams et al., 2002a,b
Ship noise (ventilation fans, in port) 81-110 dB re 1 μPa EPA, 2010
Ship noise (mean annual basis) 80-135 dB re 1 μPa Merchant et al., 2014
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Among various kinds of sound sources as of acoustic noise,
ships are permanent underwater sound sources which in-
crease the background sound level. Considering that fish can
develop tolerance to repeated exposure to underwater mo-
torboat-sounds after a certain time of sound exposure
(Nedelec et al., 2016), or even might acclimatize to environ-
mental conditions in long-term when exposed to high levels
of SPLs (149 dB re 1 μPa - 160 dB re 1 μPa) (Clark et al.,
1996; Wysocki et al., 2007; Davidson et al., 2009), the long-
term effect from the shipping industry is likely to be ac-
ceptable by marine animals. However further research is
necessary to collect more precise information. Moreover, all
the underwater noises from different industrial sources in
coastal marine environment over a long-time might produce
a cumulative effect that needs to be considered in general.
It is likely that short term marine operations such as con-
struction works of piers, cable-stayed suspension bridge or
sea-tunnel passage are of significant concern with acoustic
sound pollution through pile driving, pole drilling, dredging,
or trenching during the construction works trigger consider-
able biological impacts on marine life such as exclusion or
loss of habitat, incoherencies of behavior of marine animals.
The noise pollution generated during the operational phase
of wind farms is probably not a significant problem for ma-
rine life since fish might adapt to environmental noises in a
long-term (Wysocki et al., 2007; Davidson et al., 2009;
Nedelec et al., 2016). However, the sounds generated during
the construction phase of the industrial plants are already se-
rious problems to be considered.
Some earlier studies reported underwater noise from pile
driving in marine constructions (Nedwell et al. 2003, Black-
well et al. 2004, Rodkin & Reyff, 2004). During construc-
tion, not only the size of the pile or hammer, but also the
characteristics of the sea bottom are important that influence
the noise level and the strength of the frequency of the
sounds generated (Rodkin & Reyff, 2004). In wind farm
constructions, large pile driving units are used because of
the large foundations size. The frequency can be around 500
Hz, and the SPL can reach more than 200 dB re 1 μPa at a
distance of 100 m (PIDP, 2001; Madsen et al., 2006), which
seems to be much higher than the acoustic noise of 165 dB
re 1 μPa SPL, a level that is high enough to start an alarm
reflex of fish (Neo et al., 2014). Due, it is a clear evidence
that more research is necessary in order to assess and evalu-
ation underwater noise effects in marine living organisms
exposed to different SPLs at changing frequencies.
Once the wind turbines are deployed in a wind energy farm,
the noise from a wind turbine during operation is generated
through vibrations which are transferred in to the water am-
bience and the sea bottom via the turbine foundations. The
sound intensity may differ according to size of the wind tur-
bine and the foundation, as well as function of direction
from the wind turbine, but it was reported that the direction-
ality has not been assessed or taken into account so far in
earlier studies conducted on wind turbine noise influences
(Madsen et al., 2006). Therefore, it is important to perform
experimentations on underwater noises and biological re-
sponses of fish and invertebrates, to be able to focus on pos-
sible path to minimize the influences of underwater sounds
produced during the construction works of marine struc-
tures.
Regarding the use of acoustic monitoring and electronic de-
vices for the detection of the presence of fish and inverte-
brates, such as sonar or radar systems it is probably feasible
to develop equipment that produces a reasonable SPL lower
than the thresholds without disturbing marine live. There-
fore, the application of active acoustic monitoring is an issue
for further exploration.
Even if some kinds of acoustic noises can be tolerated by
marine animals as far as they do not exceed the hearing
thresholds of the animals, as noted also by Neo et al. (2014)
who reported an acoustic noise level of 165 dB re 1 μPa as
a SPL high enough to trigger the alarm-reflex of fish as a
fear response to predator attack. For highly sensitive species
such as Lusitanian toadfish (Halobatrachus didactylus) and
goldfsh (Cyprinus carpio), relatively lower hearing thresh-
olds of SPL below 100 dB re 1 μPa and less than 75 dB re 1
μPa were reported by Vasconcelos et al. (2007) and
Gutscher et al. (2011), respectively. Iversen (1967) reported
that yellowfin tuna (Thunnus albacares), another sound-
sensitive species is capable to detect sounds of 89 dB re 1
μPa.
Since it is almost impossible to discourage human beings
from urban life or industrialization, it seems to be important
to calculate the “threshold limits” of sounds that are accepta-
ble by -or less harmful to -marine living organisms.
Earlier studies, described above, present findings of effects
from stressors, however, “what are the environmental im-
pacts of these stressors?” This is the main question to be
considered as a whole, since the impacts can emerge either
within a population or a community of a species, in terms of
migration, habitat change or even loss of the population due
to diminishing effects on foraging behavior of the species,
as also reported as a fear-response in earlier studies
(Metcalfe et al., 1987; Wendelaar Bonga, 1997; Kusku et
al., 2018). This type of impacts on marine living organisms
Aquatic Rese arch 1(4), 140-147 (2018) DOI: 10.3153/AR18016
Original Article/Full Paper
157
can occur either through direct or indirect differentiation of
biotic or physical conditions. Even if there are no significant
evidences on population changes in the environment, any
other likely alterations in the ecological processes, such as
altered primary production, or increased nutrients in a
trophic chain. Even though these kinds of secondary effects
might be difficult to conceive in a total ecosystem, they are
important to consider when assessing environmental im-
pacts in long-term especially when cumulative effects are
the interest of research.
Conclusions
As a conclusion, in order to research any potential land-
marks for novel procedures to attenuate marine noise pollu-
tion, reliable information on acoustic noises needs collected
from ongoing marine industry activities. An important ques-
tion remains as to “how much is the noise impact of the in-
dustrial activity” and “what is the additional sound pressure
level generated by the industry?” In order to understand the
environmental effects of these kinds of marine industrial
construction works, information on the natural back-ground
noise is necessary prior to establishment of the power plants.
Therefore, researchers are encouraged to work directly with
the counterparts from the marine industries such as bridge
construction, wind energy farms, oil or -gas exploration,
which are responsible for generating a significant level of
acoustic noises. This might be a successful start for the cri-
teria to be considered in future decision-making path.
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Five cetacean species are known to inhabit the Adriatic Sea. While bottlenose dolphins (Tursiops truncatus) are the most commonly reported species of the Adriatic, they show mainly coastal distribution from its southern to the northern boundaries. On the other hand, striped dolphins (Stenella coeruleoalba), Risso’s dolphins (Grampus griseus) and Cuvier’s beaked whales (Ziphius cavirostris) show deep sea preferences to the neighbouring waters of the Adriatic Pit. Lastly, fin whales (Balaenoptera physalus) are occasionally reported in the coastal waters of Croatia, with a recent report in Montenegro in 2021. All the cetacean species present in the Adriatic Sea are classified as under threat by the IUCN Red List with extremely limited information on the deep-sea cetacean species. The dedicated research effort of Slovenia and Croatia highlighted the presence of resident bottlenose dolphins and their effort for over 20 years further advanced knowledge on species baseline information with a threat assessment which eventually resulted with the implementation of MPAs and management plans within their territorial waters. Therefore, while the northern and central Adriatic Sea is relatively well-studied, the southern Adriatic Sea still holds knowledge gaps and thus mitigation strategies are far from being implemented. Despite the scarce research efforts until the late 2010s, cetaceans have been identified as a community interest with strict protection measures enforced by the Montenegrin Government. Montenegro Dolphin Research started its dedicated cetacean research of Montenegrin waters in September 2016 and since then has been in the field for over 700 days to gather the missing knowledge on cetacean species and to understand the level of human impact on these magnificent creatures. Our results identified critical habitats of bottlenose dolphins in neighbouring waters of Ulcinj, Bar and Boka Kotorska Bay. While the estimated population size of bottlenose dolphins was 116±17 individuals in 2017, it showed a sharp decline to 79±21 individuals in 2019. However, the sighting rates of bottlenose dolphins increased from 24% in 2019 to 27% in 2020 and 47% in 2021. Since March 2020, Montenegro has had reduced human presence within the marine environment due to the COVID19 pandemic. It is interesting and also promising to see that the number of dolphin sightings immediately increased once the human pressure in the area decreased. Additionally, the inclusion of acoustic techniques in addition to the visual surveys revealed the dominant presence of foraging behaviour within the Bay of Kotor, with rare and specific vocalisation types being recorded in the area. Our previous studies in Montenegro highlighted the dominant presence of ‘travelling state’, proposing that Montenegro was mainly a migration corridor for the bottlenose dolphins. However, our recent acoustic results revealed that it also holds both foraging and socialising grounds. Last but not least, both the effect of tourism and fishery related boats revealed significant alterations to the behavioural budget of bottlenose dolphins in Montenegro, even when their exposure level to those specific boats are below 20% of the time. Montenegro is a country with a growing economy and tourism related activities are one of the main income sources. Even though eco-tourism is the one and only sustainable tourism source, the tourism industry is generally directed towards coastal development of hotels with little to no investment in their environmental impact assessment. As a result, uncontrolled coastal destruction, noise and chemical pollution, and plastic debris are already showing an impact on the marine ecosystem of Montenegro. Further, oil and gas explorations have started to take place within the coastal waters of Bar as well as in the unique deep-sea ecosystem of the Adriatic Pit with no publicly available report on the activities. Even though we are fully aware of the importance of economic growth in a country, any human activities that may be carried out in an uncontrolled and unregulated nature are likely to form severe threats to marine species and their associated habitats. Therefore, our project and its research and conservation outcomes form one of the most important steps towards effective conservation strategies that promote not only the protection of nature, but also sustainable blue economic growth. Montenegro Dolphin Research continues to be the only annual project on the field of marine mammals in Montenegro. With dedicated research efforts and engagement of the local community, knowledge about the marine mammal population in Montenegro will increase, which will give us the ability to turn our knowledge into a management plan for the conservation of cetacean populations in Montenegrin waters and its habitat. For this reason, we have created the ‘Montenegro Sighting Network’, through which we have involved the citizens of Montenegro and in 11 months we have received 23 reports, which shows that public awareness about cetaceans and marine ecosystems in general is increasing in Montenegro. By establishing networks and producing influential documentation within the community, the conservation implications of our actions will be more effective and longer lasting.
... Underwater noise pollution is now a globally-recognized conservation concern for aquatic animals (Erbe et al., 2012;Frisk, 2012;Cox et al., 2018;Kuşku et al., 2018;Pirotta et al., 2019). Noise-generating human activities in marine environments such as commercial shipping, recreational boating, pile-driving, seismic exploration, and offshore energy production are widespread and increasing (Hildebrand, 2009), and noise from these activities, even if undertaken outside of marine protected areas, propagates into marine protected areas (Buscaino et al., 2016). ...
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... The monitoring of underwater noise generated by ships has been a topic of interest to research scientists for several years [11,14], and measurement standards have been developed for this type of noise [10]. One area of research is the impact of noise on the natural environment [2,12], and in particular on underwater fauna, which researchers from many institutes and pro-ecological organisations have focused on [3,15]. Another aspect is mechanical engineering methods of diagnostics for ship equipment [9,13], using on-board and external measurement systems. ...
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A ship moving over the surface of water generates disturbances that are perceived as noise, both in the air and under water. Due to its density, water is an excellent medium for transmitting acoustic waves over long distances. This article describes the impact of the settings of a ship’s machinery on the nature of the generated noise. Our analysis includes the frequency characteristics of the noise generated by the moving ship. Data were obtained using an underwater measurement system, and the measured objects were two ships moving on specific trajectories with certain machinery settings. The acquired data were analysed in the frequency domain to explore the possibilities of the acoustic classification of ships and diagnostics of source mechanisms.
... The economic development of coastal zones in recent years has led to increased coastal infrastructure. This in turn requires appropriate security measures and environmental monitoring to carry out a long-term assessment of the impact of investments on the marine environment [1,2]. Economic development in the coastal area is associatedwith the development of ports and the increase in the volume of goods sent by the sea, thus affecting the dynamics of the transport. ...
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The development of coastal infrastructure and related maritime transport necessitatesthe intensification of vessel traffic monitoring. Navigation systems used in this research are traditionally based on the information transmitted by radio waves. Marine traffic safety requires constant supervision carried out by dedicated systems, the operation of which may be limitedby difficult environmental conditions. The possibilities of supporting navigation systems with underwater observation systems are explored here. The research was carried out using an underwater measurement system. Local disturbances of the hydroacoustic and hydrodynamic field from the moving vessels were analysed. The potential for identifying a moving vessel, for example for offshore infrastructure security purposes, is demonstrated.
... Further, these undesirable impacts could be seen even at low frequencies overlapping hearing ability levels in fishes (Popper and Fay 2011). Even though researchers pay more attention on consequences of underwater sound pollution with increasing public concern (André 2009;Kusku et al. 2018;Kusku et al. 2020), still little information is available so far about how noise pollution affects aquatic animals (Slabbekoorn et al. 2010). ...
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Human-made impacts on the acoustic environment from marine industries is becoming a more significant issue with increasing public concern of environmental consequences. Even though there are several reports with scientific evidences on harmful influences of anthropogenic underwater sounds on the aquatic ecosystem, most of the studies so far dealt with trigger effects of short term noise impacts on aquatic animals. In the present study, however, long-term experimentation was conducted with Nile tilapia (Oreochromis niloticus) in order to figure out how fish may respond to long-term exposure of underwater sounds and if the level of response may change (increase or decline) over time. A startle reflex as a sign of stress was seen immediately at the start of the playbacks of ship noise or urban sounds in this study. Peaks of elevated respiratory movements of ventilation (opercula beats and pectoral wing rates) retained high over the following 30 days of sound initiation and underwent a declining trend over the following 90 days of exposure. At the end of the 120-day study period, the lowered response of fish after long-term sound exposure is likely due to the increased tolerance of fish to human-generated underwater sounds of urban and shipping noises. Different than short-term noise impacts, information on long-term exposure of anthropogenic underwater sounds is important for environmental management and setting new regulations for the sustainable use of water resources in the world.
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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.
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The Yangtze River exhibits a high biodiversity and plays an important role in global biodiversity conservation. As the world's busiest inland river in regard to shipping, little attention has been paid to underwater noise pollution. In 2017, the underwater noise level in 25 riverside locations along the middle and lower reaches of the Yangtze River mainly at night time were investigated by using passive acoustic monitoring method. Approximately 88% and 40% of the sampled sites exhibit noise levels exceeding the underwater acoustic thresholds of causing responsiveness and temporary threshold shift, respectively, in cetacean. Noise pollution may impose a high impact on fish with physostomous swim bladders and Weberian ossicles, such as silver carp, bighead carp, goldfish and common carp, whereas it may affect fish with physoclistous swim bladders and without Weberian ossicles, such as lake sturgeon and paddlefish, to a lesser extent. Noise levels reductions of approximately 10 and 20 dB were observed in the middle and lower reaches, respectively, of the Yangtze River over the 2012 level. The green development mode of the ongoing construction of green shipping in the Yangtze River Economic Belt, including the development of green shipping lanes, ports, ships and transportation organizations, may account for the alleviated underwater noise pollution. Follow-up noise mitigation endeavors, such as the extension of ship speed restrictions and the study and implementation of the optimal navigation speed in ecologically important areas, are required to further reduce the noise level in the Yangtze River to protect local porpoises and fish.
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In the present study, effects of underwater sound transmission on growth, feed utilization and behavior of Koi fish (Cyprinus carpio, initial weight 3.67±0.18 g) was investigated via exposure to Urban Noise, Silk Road, Sufi Ney, and a Quran performance. Underwater sound transmissions were performed daily with playbacks between 08:00-08.30, 12:30-13:00, and 17:00-17:30 hours, throughout the feeding trial for a period of 90 days in a recirculating aquaculture system. An experimental group without any sound served as control. Results showed that musical stimuli tested in this study positively influenced fish growth and feed efficiency. Experimental fish presented slow growth performance during the first period however the disturbed swimming behavior of fish scattering in the tanks changed to a more regular swimming and improved growth thereafter, an indication of lower stress condition or acclimatization of fish to sounds. As a result, fish growths and feed efficiencies were influenced by musical stimuli with remarkably higher rates in the Quran performance and instrumental Sufi Ney treatments, compared to the Silk Road or the control group. Urban noise presented adverse effect on fish growth and feed efficiency. Hence, musical stimuli could be considered as a growth promoting factor ensuring fish welfare in intensive aquaculture facilities.
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Anthropogenic noise is a significant pollutant of the world's oceans, affecting behavioural and physiological traits in a range of species, including anti-predator behaviours. Using the open field test, we investigated the effects of recordings of piling and drilling noise on the anti-predator behaviour of captive juvenile European seabass in response to a visual stimulus (a predatory mimic). The impulsive nature of piling noise triggered a reflexive startle response, which contrasted the behaviour elicited by the continuous drilling noise. When presented with the predatory mimic, fish exposed to both piling and drilling noise explored the experimental arena more extensively than control fish exposed to ambient noise. Fish under drilling and piling conditions also exhibited reduced predator inspection behaviour. Piling and drilling noise induced stress as measured by ventilation rate. This study provides further evidence that the behaviour and physiology of European seabass is significantly affected by exposure to elevated noise levels.
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The effects of different tempos of music on growth, body chemical composition and feeding parameters of turbot (Psetta maeotica, Pallas 1814) were investigated. Turbot (average weight 160.61 +/- 1.53 g) were reared in a circulating sea water system for 8 weeks with music playing for 5 hours at each feeding. The music treatments consisted of slow tempo music (adagio; metronome speed 66-76), medium tempo music (moderate; metronome speed 108-120), fast tempo music (allegro; metronome speed 120-168) and control group (no music). Results demonstated that the fast tempo music treatment (FTM, p<0.01) had a negative effect on fish growth, but when slow tempo music (STM) was transmitted, growth improved slightly. Best growth performance was observed when the fish were exposed to slow tempo music. The FTM group showed signs of stress and reduced feed intake. Music transmission significantly affected carcass fat content (p<0.05). No significant effect was observed on protein, ash or moisture content.
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