Results of low-frequency playback of M-sequence noise to humpback whales, Megaptera novaeangliae, in Hawai′i

1998 ◽  
Vol 76 (3) ◽  
pp. 521-535 ◽  
Author(s):  
A S Frankel ◽  
C W Clark
Keyword(s):  
Biological Significance ◽  
Low Frequency ◽  
Sine Wave ◽  
Sound Level ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Sound Levels ◽  
M Sequence ◽  
Behavioral Variables ◽  
Source Signal

The behavior of humpback whales, Megaptera novaeangliae, exposed to playback of low-frequency sounds, was examined to test whether animals would respond to this signal when received sound levels exceeded 120 dB re: 1 µPa. The source signal was an M-sequence (essentially a sine wave with a series of phase reversals) centered at 75 Hz with a 30-Hz bandwidth. Behavior and movements of whales were described before, during, and after playback. Eighty-five trials were conducted, of which 50 had an experimental condition of M-sequence playback. Thirty-four were no-sound controls and a single trial used a playback of the Alaska humpback whale feeding call. The received playback sound level at the whales ranged from ambient level ( approx 90 dB) to 130 dB re: 1 µPa (60-90 Hz). A comparison revealed no difference in whale tracks and bearings between control and playback conditions. Behavior rates were examined statistically using independent variables describing pod composition, nearby vessels, and playback sound level. Natural variables of pod composition were the most important factors predicting behavior rates. Vessels had a larger impact and affected more behavioral variables than playback. A slight increase in the duration and distance between successive surfacings was found as the received playback sound level increased. Eleven playbacks in which whales passed within the 120-dB isopleth yielded only three potential responses (one movement away and two toward the sound source) and eight nonresponses. Overall, subtle responses to M-sequence playbacks could only be detected statistically, but the biological significance of these responses is uncertain.

Incubator Noise

PEDIATRICS ◽  
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.

scholarly journals INFRASOUND AND LOW FREQUENCY NOISE IMMISION FROM PIPELINES. iMPROVING THE ISO 1996-2:2017 PROPOSED METHODS. CASES STUDIES CONDUCTED AT LOS ANDES AND PERUVIAN RAINFOREST

Akustika ◽  
2019 ◽  
Vol 32 ◽  
pp. 335-345
Author(s):  
Walter Montano
Keyword(s):  
Low Frequency ◽  
Sound Level ◽  
Frequency Noise ◽  
Gas Extraction ◽  
Howler Monkeys ◽  
Noise Sources ◽  
Industrial Facilities ◽  
Sound Levels ◽  
Continuous Noise ◽  
Amazonian Rainforest

The gas extraction wells are in Amazonian rainforest and by them there are their industrial facilities. The pipeline has about 800 km with four pumps stations and two compressor stations. The challenge of conducting sound measurements was important-there is no specialized literature-and other noise "sources" are howler monkeys, cicadidae chirping, woodpeckers, trees´foliage, etc. However the problem is simply because those fixed industrial facilities are the only ones. People live in isolated hamlet on the side of dirt roads, so they are exposed 24/7 to the continuous noise; at homes 4 km away from the plants the sound level is 60 dBC, but in the spectrum of ILFN tones could not be identified. This Paper presents the procedures that were developed to identify the ILFN tones, improving the methods proposed in ISO 1996-2, writing a software that "automatically eliminates" the sound levels that don´t belong to the industry,

scholarly journals How Can Low-Frequency Noise Exposure Interact with the Well-Being of a Population? Some Results from a Portuguese Municipality

2019 ◽  
Vol 9 (24) ◽  
pp. 5566 ◽  
Author(s):  
Juliana Araújo Alves ◽  
Lígia Torres Silva ◽  
Paula Remoaldo
Keyword(s):  
Urban Areas ◽  
Noise Exposure ◽  
Low Frequency ◽  
Noise Pollution ◽  
Well Being ◽  
Sound Level ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Sound Levels ◽  
Exposed Population

Noise pollution is the second most harmful environmental stressor in Europe. Portugal is the fourth European country most affected by noise pollution, whereby 23.0% of the population is affected. This article aims to analyze the effects of exposure to low frequency noise pollution, emitted by power poles and power lines, on the population’s well-being, based on a study of “exposed” and “unexposed” individuals in two predominantly urban areas in north-western Portugal. To develop the research, we used sound level (n = 62) and sound recording measurements, as well as adapted audiometric test performance (n = 14) and surveys conducted with the resident population (n = 200). The sound levels were measured (frequency range between 10 to 160 Hz) and compared with a criterion curve developed by the Department for Environment, Food and Rural Affairs (DEFRA). The sound recorded was performed 5 m away from the source (400 kV power pole). Surveys were carried out with the “exposed” and “unexposed” populations, and adapted audiometric tests were performed to complement the analysis and to determine the threshold of audibility of “exposed” and “unexposed” volunteers. The “exposed” area has higher sound levels and, consequently, more problems with well-being and health than the “unexposed” population. The audiometric tests also revealed that the “exposed” population appears to be less sensitive to low frequencies than the “unexposed” population.

Measurement and Analysis of the Structural Noise of Urban Bridges

2014 ◽  
Vol 548-549 ◽  
pp. 1623-1626
Author(s):  
Tao Jin ◽  
Qi Huang ◽  
Yong Ding ◽  
Li Feng Zhu
Keyword(s):  
Sound Pressure ◽  
Low Frequency ◽  
Measured Data ◽  
Sound Level ◽  
Frequency Noise ◽  
Acoustic Environment ◽  
The Road ◽  
Sound Levels ◽  
Measurement And Analysis ◽  
The City

To explore the noise generated by bridges during operational period, the equivalent continuous sound pressure levels of 12 bridges in the city of Ningbo were measured and analyzed. The measured data show that (1) Although the measured sound levels of these bridges meet the requirement of Chinese codes, they are near the maximum limit and the vibration and noise reduction is necessary; (2) A-weighted sound level of bridge is close to that of the road nearby; (3) Z-weighted sound level of bridge is much greater than that of the road nearby, it indicates that the bridge noise contains much low frequency noise, so that A-weighted sound level can’t reflect the noise of bridge accurately, and Z-weighted sound level shall be used to evaluate the acoustic environment near bridges.

Health effects related to wind turbine sound: A review

2021 ◽  
Vol 263 (1) ◽  
pp. 5415-5423
Author(s):  
Irene van Kamp ◽  
Frits van den Berg
Keyword(s):  
Wind Turbine ◽  
Health Effects ◽  
Scientific Literature ◽  
Low Frequency ◽  
Sound Level ◽  
Costs And Benefits ◽  
Sound Levels ◽  
Local Decision ◽  
Local Residents ◽  
Local Decision Making

Worldwide questions about health effects play a role in local debates about windfarms. A review was prepared for the Swiss Federal Office for the Environment of the literature published since 2017 about the health-effects of wind turbine sound. Scientific literature was collected on the effect on annoyance, sleep disturbance, cardiovascular disease and metabolism. Also, visual annoyance and other non-acoustic factors, such as appraisal of the local decision making process were investigated. Annoyance came forward as a consequence of wind turbine sound: the louder the receiver sound level, the stronger the annoyance response. For other health effects, results of scientific research are inconsistent. Effect are not a consequence of the sound levels, but rather related to the residents' annoyance. The literature did not show that infrasound or low frequency sound leads to other effects when compared to sound at higher frequencies. Evidence shows that residents experience less annoyance when they participate in the siting process. By being able to take part in the siting and in balancing costs and benefits, residents experience less annoyance. It is therefore important to take worries of local residents seriously and involve them in the process of planning and the siting of wind turbines.

scholarly journals First analysis of behavioural responses of humpback whales (Megaptera novaeangliae) to two acoustic alarms in a northern feeding ground off Iceland

2019 ◽  
Author(s):  
Charla J. Basran ◽  
Benno Woelfing ◽  
Charlotte Neumann ◽  
Marianne H. Rasmussen
Keyword(s):  
Swimming Speed ◽  
Low Frequency ◽  
Mixed Effects ◽  
Megaptera Novaeangliae ◽  
Mixed Effects Models ◽  
Humpback Whales ◽  
Mitigation Measures ◽  
Linear Mixed Effects Models ◽  
Linear Mixed Effects ◽  
Feeding Grounds

AbstractMitigating cetacean entanglement in fishing industries is of global interest. Strategies include the use of acoustic alarms to warn whales of fishing gear. For baleen whales, responses to acoustic alarms are poorly understood. This behavioural response study compared the behaviour of humpback whales (Megaptera novaeangliae) in their feeding grounds off Iceland prior to, during, and after exposure to a low-frequency whale pinger (Future Oceans) and a high-frequency seal scarer (Lofitech ltd.). Linear mixed effects models and binary generalized linear mixed effects models were used to analyze the effect of the alarms on surface feeding, swimming speed, breathing rate, directness and dive time. We observed a significant decrease in surface feeding and a significant increase in swimming speed during exposure to the whale pinger. Changes in dive time between the phases of a trial differed significantly between individuals indicating that responses may depend on individual or behavioural state. We did not find any significant reactions in response to the seal scarer. In addition to the experimental exposures, a trial of whale pingers on a capelin purse seine net was conducted. Results from this trial showed that whales entered the net from the bottom while the pingers were attached at the top, but the encircled whales were able to locate an opening free of pingers and escape without damaging the net. Our results suggest that whale pingers may be a useful entanglement mitigation tool in humpback whale feeding grounds given that a reduction in feeding around nets likely reduces the risk of whales swimming through them. Pingers may also minimize net damage if whales are encircled by aiding the whales in finding their way out. However, given the uncertain long-term consequences of the behavioural changes reported here, whale pingers are most advisable for short-term use in conjunction with other entanglement mitigation measures.

SOURCES OF SOUND LEVELS IN NICU AND INCUBATOR

2021 ◽  
pp. 18-20
Author(s):  
Dilip Kumar ◽  
V Shankar Vengalapudi ◽  
Maneesha Panduranga Halkar ◽  
Ranjan Kumar Pejaver
Keyword(s):  
Low Frequency ◽  
Sound Level ◽  
Assessment System ◽  
Frequency Noise ◽  
Intrauterine Environment ◽  
Sound Levels ◽  
Auditory Development ◽  
Level Ii ◽  
Level 3 ◽  
Level 2

Introduction: Currently there is limited research regarding estimated intrauterine sound levels. Benzaquen, Gagnon, Hunse& Foreman (1990) suggest however that intrauterine noise consists predominantly of low-frequency noise with sound levels being 40 dB above 500 Hz. Ideally, to promote healthy auditory development, sound levels in the NICU should be consistent with intrauterine environment. Each part has two sections A and B, the section A Methodology: is from more sick babies requiring Level 3 NICU care, whereas the section B is for babies requiring Level 2 NICU care. Our unit is 20 beded NICU with 15 beds level III and 5 beds level II unit, the study was conducted in level III unit. All sources of noise levels higher than 55 dBA in the NICU n Results: eed to be eliminated or mitigated. Since the alarms of equipments were important sources of noise in the NICU, eliminating or decreasing volume of alarms will reduce sound level. Every NICU requires a sound level assessment system in order to achieve environmental noise limiting guidelines and to get closer to the standard sound levels. Conclusion:By evaluating sound levels, the sources of noise can be identied and their effects on sound levels can be studied.

scholarly journals Fluctuations in Hawaii’s humpback whale Megaptera novaeangliae population inferred from male song chorusing off Maui

2020 ◽  
Vol 43 ◽  
pp. 421-434
Author(s):  
A Kügler ◽  
MO Lammers ◽  
EJ Zang ◽  
MB Kaplan ◽  
TA Mooney
Keyword(s):  
North Pacific ◽  
Low Frequency ◽  
Humpback Whale ◽  
Megaptera Novaeangliae ◽  
Acoustic Energy ◽  
Humpback Whales ◽  
Underwater Sound ◽  
The North ◽  
The Pacific ◽  
The North Pacific

Approximately half of the North Pacific humpback whale Megaptera novaeangliae stock visits the shallow waters of the main Hawaiian Islands seasonally. Within this breeding area, mature males produce an elaborate acoustic display known as song, which becomes the dominant source of ambient underwater sound between December and April. Following reports of unusually low whale numbers that began in 2015/16, we examined song chorusing recorded through long-term passive acoustic monitoring at 6 sites off Maui as a proxy for relative whale abundance between 2014 and 2019. Daily root-mean-square sound pressure levels (RMS SPLs) were calculated to compare variations in low-frequency acoustic energy (0-1.5 kHz). After 2014/15, the overall RMS SPLs decreased between 5.6 and 9.7 dB re 1 µPa2 during the peak of whale season (February and March), reducing ambient acoustic energy from chorusing by over 50%. This change in song levels co-occurred with a broad-scale oceanic heat wave in the northeast Pacific termed the ‘Blob,’ a major El Niño event in the North Pacific, and a warming period in the Pacific Decadal Oscillation cycle. Although it remains unclear whether our observations reflect a decrease in population size, a change in migration patterns, a shift in distribution to other areas, a change in the behavior of males, or some combination of these, our results indicate that continued monitoring and further studies of humpback whales throughout the North Pacific are warranted to better understand the fluctuations occurring in this recently recovered population and other populations that continue to be endangered or threatened.

scholarly journals Year-round acoustic presence of sperm whales (Physeter macrocephalus) and baseline ambient ocean sound levels in the Greek Seas

2019 ◽  
Vol 20 (1) ◽  
pp. 208 ◽  
Author(s):  
NIKOLETTA DIOGOU ◽  
HOLGER KLINCK ◽  
ALEXANDROS FRANTZIS ◽  
JEFFREY A. NYSTUEN ◽  
EVANGELOS PAPATHANASSIOU ◽  
...  
Keyword(s):  
Low Frequency ◽  
Weather Conditions ◽  
Sperm Whale ◽  
Distribution Patterns ◽  
Sound Level ◽  
Anthropogenic Sources ◽  
Mitigation Measures ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Sound Levels

The sperm whale (Physeter macrocephalus) is the largest odontocete occurring in the Greek Seas. However, monitoring thespecies’ spatiotemporal distribution patterns is especially difficult during the winter months when unfavorable weather conditionsoften hinder survey efforts. In the Greek Seas, visual cetacean surveys are typically not conducted between November and March. In a first attempt to collect year-round baseline information on sperm whale occurrence patterns in Greek waters, two Passive Aquatic Listeners (PALs) were deployed for 19 months, at Pylos Station (36.8 N, 21.6ο E) in the Hellenic Trench, and at Athos Station (40.0 N, 24.7ο E) in the North Aegean Trough. Results revealed the year-round presence of sperm whales at Pylos Station with a higher number of detections observed during late spring and throughout the summer. No sperm whale vocalizations were detected at Athos Station. An ambient sound level analysis revealed higher winter and lower summer levels at both sites largely driven by local weather conditions. Results showed that marine life in the Hellenic Trench area was exposed to higher low frequency (< 1 kHz) sound levels (by up to 10 dB re 1 μPa2/Hz). Ambient noise below 1 kHz is frequently dominated by anthropogenic sources including shipping. Ship strikes and noise disturbance constitute major threats for the small, genetically isolated, endangeredsperm whale population. The results of this study are useful for sperm whale conservation efforts in the region and may helppolicymakers in prioritizing mitigation measures, including the establishment of speed limits and rerouting of ship traffic.

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