Large Vessel Activity and Low-Frequency Underwater Sound Benchmarks in United States Waters

Chronic low-frequency noise from commercial shipping is a worldwide threat to marine animals that rely on sound for essential life functions. Although the U.S. National Oceanic and Atmospheric Administration recognizes the potential negative impacts of shipping noise in marine environments, there are currently no standard metrics to monitor and quantify shipping noise in U.S. marine waters. However, one-third octave band acoustic measurements centered at 63 and 125 Hz are used as international (European Union Marine Strategy Framework Directive) indicators for underwater ambient noise levels driven by shipping activity. We apply these metrics to passive acoustic monitoring data collected over 20 months in 2016–2017 at five dispersed sites throughout the U.S. Exclusive Economic Zone: Alaskan Arctic, Hawaii, Gulf of Mexico, Northeast Canyons and Seamounts Marine National Monument (Northwest Atlantic), and Cordell Bank National Marine Sanctuary (Northeast Pacific). To verify the relationship between shipping activity and underwater sound levels, vessel movement data from the Automatic Identification System (AIS) were paired to each passive acoustic monitoring site. Daily average sound levels were consistently near to or higher than 100 dB re 1 μPa in both the 63 and 125 Hz one-third octave bands at sites with high levels of shipping traffic (Gulf of Mexico, Northeast Canyons and Seamounts, and Cordell Bank). Where cargo vessels were less common (the Arctic and Hawaii), daily average sound levels were comparatively lower. Specifically, sound levels were ∼20 dB lower year-round in Hawaii and ∼10-20 dB lower in the Alaskan Arctic, depending on the season. Although these band-level measurements can only generally facilitate differentiation of sound sources, these results demonstrate that international acoustic indicators of commercial shipping can be applied to data collected in U.S. waters as a unified metric to approximate the influence of shipping as a driver of ambient noise levels, provide critical information to managers and policy makers about the status of marine environments, and to identify places and times for more detailed investigation regarding environmental impacts.

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Incubator Noise

PEDIATRICS ◽

10.1542/peds.56.4.617 ◽

1975 ◽

Vol 56 (4) ◽

pp. 617-617

Author(s):

Gōsta Blennow ◽

Nils W. Svenningsen ◽

Bengt Almquist

Keyword(s):

Low Frequency ◽

Sound Level ◽

Noise Levels ◽

Frequency Sound ◽

Mechanical Noise ◽

Sound Levels ◽

Infant Incubator ◽

Improved Model ◽

Model C

Recently we reported results from studies of incubator noise levels.1 It was found that in certain types of incubators the noise was considerable, and attention was called to the sound level in the construction of new incubators. Recently we had the opportunity to study an improved model of Isolette Infant Incubator Model C-86 where the mechanical noise from the electrically powered motor has been partially eliminated. With this modification it has been possible to lower the low-frequency sound levels to a certain degree in comparison to the levels registered in our study.

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Exploring sperm whale population demographics in the northern Gulf of Mexico using passive acoustic monitoring

The Journal of the Acoustical Society of America ◽

10.1121/10.0007582 ◽

2021 ◽

Vol 150 (4) ◽

pp. A47-A47

Author(s):

Renea Briner ◽

Natalia Sidorovskaia ◽

Naomi Mathew

Keyword(s):

Gulf Of Mexico ◽

Sperm Whale ◽

Acoustic Monitoring ◽

Passive Acoustic Monitoring ◽

Population Demographics ◽

Northern Gulf Of Mexico ◽

Passive Acoustic

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MobiLab – A Mobile Laboratory for On-Site Listening Experiments in Virtual Acoustic Environments

Acta Acustica united with Acustica ◽

10.3813/aaa.919367 ◽

2019 ◽

Vol 105 (5) ◽

pp. 875-887

Author(s):

Florian Pausch ◽

Janina Fels

Keyword(s):

Ambient Noise ◽

Low Frequency ◽

Mobile Laboratory ◽

Noise Levels ◽

Acoustic Parameters ◽

Research Areas ◽

Test Conditions ◽

Acoustic Environments ◽

Study Participants ◽

Insulation Performance

Virtual acoustic environments have demonstrated their versatility for conducting studies in various research areas as they allow easy manipulations of experimental test conditions or simulated acoustic scenes, while providing expansion possibilities to related interdisciplinary and multimodal fields. Although the evolution of auditory and cognitive models is consistently pursued, listening experiments are still considered the gold standard, usually necessitating a large amount of resources, including travel expenses of study participants. In order to facilitate practical and efficient study execution, we therefore implemented a mobile hearing laboratory by acoustically optimising the interior of a caravan. All necessary technical facilities were integrated to perform listening experiments in virtual acoustic environments under controlled conditions directly on site, for example, in front of schools or senior residential centers. The design and construction of this laboratory are presented and evaluated based on insulation properties, selected room acoustic parameters, and interior ambient noise levels that are to be expected during operation at representative test sites. Limitations, particularly in low-frequency insulation performance, should provide incentives for further optimisations in similar future projects.

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New Insights into the Design and Application of a Passive Acoustic Monitoring System for the Assessment of the Good Environmental Status in Spanish Marine Waters

Sensors ◽

10.3390/s20185353 ◽

2020 ◽

Vol 20 (18) ◽

pp. 5353

Author(s):

Guillermo Lara ◽

Ramón Miralles ◽

Manuel Bou-Cabo ◽

José Antonio Esteban ◽

Víctor Espinosa

Keyword(s):

Ambient Noise ◽

Ad Hoc ◽

Acoustic Monitoring ◽

Passive Acoustic Monitoring ◽

Acoustic Signatures ◽

Environmental Status ◽

Boat Traffic ◽

Using Data ◽

Passive Acoustic ◽

User Friendly

Passive acoustic monitoring systems allow for non-invasive monitoring of underwater species and anthropogenic noise. One of these systems has been developed keeping in mind the need to create a user-friendly tool to obtain the ambient noise indicators, while at the same time providing a powerful tool for marine scientists and biologists to progress in studying the effect of human activities on species and ecosystems. The device is based on a low-power processor with ad-hoc electronics, ensuring that the system has efficient energy management, and that the storage capacity is large enough to allow deployments for long periods. An application is presented using data from an acoustic campaign done in 2018 at El Gorguel (Cartagena, Spain). The results show a good agreement between theoretical maps created using AIS data and the ambient noise level indicators measured in the frequency bands of 63 Hz and 125 Hz specified in the directive 11 of the EU Marine Strategy Framework Directive. Using a 2D representation, these ambient noise indicators have enabled repetitive events and daily variations in boat traffic to be identified. The ship noise registered can also be used to track ships by using the acoustic signatures of the engine propellers’ noise.

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Cues, creaks, and decoys: using passive acoustic monitoring as a tool for studying sperm whale depredation

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv024 ◽

2015 ◽

Vol 72 (5) ◽

pp. 1621-1636 ◽

Cited By ~ 13

Author(s):

Aaron Thode ◽

Delphine Mathias ◽

Janice Straley ◽

Victoria O'Connell ◽

Linda Behnken ◽

...

Keyword(s):

Low Frequency ◽

Field Tests ◽

Sperm Whale ◽

Acoustic Monitoring ◽

Sperm Whales ◽

Passive Acoustic Monitoring ◽

Long Distance ◽

Fishing Activity ◽

Fishing Vessels ◽

Passive Acoustic

Abstract Since 2003, a collaborative effort (SEASWAP) between fishers, scientists, and managers has researched how Alaskan sperm whales locate demersal longline fishing activity and then depredate sablefish from gear. Sperm whales constantly produce relatively low-frequency biosonar signals whenever foraging; therefore, over the past decade, passive acoustic monitoring (PAM) has become a basic tool, used for both measuring depredation activity and accelerating field tests of potential depredation countermeasures. This paper reviews and summarizes past published PAM research on SEASWAP, and then provides a detailed example of how PAM methods are currently being used to test countermeasures. The review covers two major research thrusts: (i) identifying acoustic outputs of fishing vessels that provide long-distance “cues” that attract whales to fishing activity; and (ii) validating whether distinctive “creak” sounds can be used to quantify and measure depredation rates, using both bioacoustic tags and statistical comparisons between visual and acoustic depredation estimates during federal sablefish surveys. The latter part of the paper then provides an example of how PAM is being used to study a particular potential countermeasure: an “acoustic decoy” which transmits fishing vessel acoustic cues to attract animals away from true fishing activity. The results of an initial 2011 field trial are presented to show how PAM was used to design the decoy signals and monitor the efficacy of the deployment. The ability of PAM to detect both whale presence and depredation behaviour has reduced the need to deploy researchers or other specialists on fishing cruises. Instead, volunteer fishers can deploy “user-friendly” acoustic recorders on their gear, greatly facilitating the testing of various deterrents, and providing the industry and regulators a convenient and unobtrusive tool for monitoring both the scale and long-term spread of this behaviour across the Alaskan fishery.

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