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In the Southeast USA, major contributors to estuarine soundscapes are the courtship calls produced by fish species belonging to the family Sciaenidae. Long-term monitoring of sciaenid courtship sounds may be valuable in understanding reproductive phenology, but this approach produces massive acoustic datasets. With this in mind, we designed a feature-based, signal detector for sciaenid fish calls and tested the efficacy of this detector against manually reviewed data. Acoustic recorders were deployed to collect sound samples for 2 min every 20 min at four stations in the May River estuary, South Carolina, USA from February to November, 2014. Manual analysis of acoustic files revealed that four fish species, belonging to the family Sciaenidae, were the major sound producers in this estuarine soundscape, and included black drum (Pogonias cromis), silver perch (Bairdiella chrysoura), spotted seatrout (Cynoscion nebulosus), and red drum (Sciaenops ocellatus). Recorded calls served as an acoustic library of signature features that were used to create a signal detector to automatically detect, classify, and quantify the number of calls in each acoustic file. Correlation between manual and automatic detection was significant and precision varied from 61% to 100%. Automatic detection provided quantitative data on calling rates for this long-term data set. Positive temperature anomalies increased calling rates of black drum, silver perch, and spotted seatrout, while negative anomalies increased calling rates of red drum. Acoustic monitoring combined with automatic detection could be an additional or alternative method for monitoring sciaenid spawning and changes in phenology associated with climate change. [ABSTRACT FROM AUTHOR]

Invasive silver carp (Hypophthalmichthys molitrix) dominate large regions of the Mississippi River drainage, outcompete native species, and are notorious for their prolific and unusual jumping behavior. High densities of juvenile and adult (~25 kg) carp are known to jump up to 3 m above the water surface in response to moving watercraft. Broadband sound recorded from an outboard motor (100 hp at 32 km/hr) can modulate their behavior in captivity; however, the response of wild silver carp to broadband sound has yet to be determined. In this experiment, broadband sound (0.06–10 kHz) elicited jumping behavior from silver carp in the Spoon River near Havana, IL independent of boat movement, indicating acoustic stimulus alone is sufficient to induce jumping. Furthermore, the number of jumping fish decreased with subsequent sound exposures. Understanding silver carp jumping is not only important from a behavioral standpoint, it is also critical to determine effective techniques for controlling this harmful species, such as herding fish into a net for removal. [ABSTRACT FROM AUTHOR]

The endangered North Atlantic right whale is susceptible to increased risks associated with the developing energy market off the Virginia coast of the U.S.A., including increased noise exposure from shipping and energy exploration and extraction, and shipping activity. Primarily viewed as a migratory corridor between northern feeding and mating areas and the southern calving area, Virginia waters have not been intensely monitored for right whales. We conducted a 1 yr, continuous, passive acoustic survey from the Virginia coast to the continental shelf to better describe the seasonal occurrence and spatial distribution of right whales in this area. We found that whales were acoustically detected in every month of the year, with increased seasonal occurrences in fall and late winter/early spring, and not just during limited periods of the year. As industry activities continue to increase in the area, these new right whale occurrence data have implications for siting and permitting of offshore energy activities. [ABSTRACT FROM AUTHOR]

Delimiting species is important to every subfield in biology. Templeton's cohesion species concept uses genetic and ecological exchangeability to identify sets of populations that ought to be considered as the same species, and the lack of exchangeability helps determine which populations can be grouped as evolutionarily significant units (ESU) in conservation science. However, previous work assessing genetic and ecological interchangeability among populations has been limited in scope. Here, we provide a method for assessing exchangeability that incorporates multiple, independent lines of multivariate evidence in genetic, behavioural and morphological data. We use this approach to assess exchangeability across three disjunct groups of populations of the Pine Barrens Treefrog ( Hyla andersonii) from the eastern United States. This species is considered threatened by each state in which it occurs and conservation management of this taxon requires a clearer understanding of how populations in these three regions may differ from one another. We find a strikingly concordant pattern in which the first axis of variation for each of the three types of data distinguishes populations along a latitudinal gradient and the second axis distinguishes the set of populations occurring in the Carolinas from those occurring in the New Jersey and Florida/Alabama regions. We know of no comparable data set that displays such concordance among different types of data across so large a geographic range. The overlap in trait values (i.e. exchangeability) between neighbouring regions, however, is substantial in all three types of data, which supports continued consideration of this taxon as a single species. [ABSTRACT FROM AUTHOR]

Abstract: Fine-structure (centimeters to meters) in vertical profiles of acoustic volume scattering strength is a common and ecologically significant characteristic of the coastal marine water column. The processes that create these structures modify the availability of food and exposure to predation for secondary producers at and below spatial and temporal scales that characterize their daily ambits. Thin acoustic scattering layers may persist for weeks at a particular coastal location, but they may also appear and disappear in only a few hours. These layers are usually evidence of mesozooplankton and micronekton having aggregated at peaks, gradients, or boundaries in the vertical distribution of various water column properties that characterize a marine ecosystem. The behaviors of both predators and prey are implicated in the generation of complex, time-dependent patterns of fine-structure. Specifically, diel vertical migration to layers of prey, isolumes, isotherms, isopycnals, or chemoclines can be responsible for the nighttime formation of thin acoustic layers. Physical processes such as horizontal shear, internal waves, water mass intrusions, tidal forcing, wind mixing of the upper water column, and horizontal advection modify acoustic scattering patterns by changing the vertical distributions of organisms that scatter sound. [Copyright &y& Elsevier]

Vocalizations from the northern right whale dolphin, Lissodelphis borealis, were recorded during a combined visual and acoustic shipboard survey of cetacean populations off the west coast of the United States. Seven of twenty single-species schools of L. borealis produced click and pulsed vocalizations. No whistles were detected during any of the encounters. Clicks associated with burst-pulse vocalizations were lower in frequency and shorter in duration than clicks associated with echolocation. All burst-pulse sounds were produced in a series containing 6–18 individual burst-pulses. These burst-pulse series were stereotyped and repeated. A total of eight unique burst-pulse series were detected. Variation in the temporal characteristics of like units compared across repeated series was less than variation among all burst-pulses. These stereotyped burst-pulse series may play a similar communicative role as do stereotyped whistles found in other delphinid species. [ABSTRACT FROM AUTHOR]

Distortion product otoacoustic emission (DPOAE) suppression tuning curves (STCs) typically are constructed using suppression criteria of 3 or 6 dB. This paper describes a technique for generating DPOAE STCs using criteria ranging from 3 dB to complete suppression. The criterion effect was examined at various primary levels (f2=4 kHz) in normal-hearing ears. As expected, QERB and tip-to-tail differences decreased as probe level (L2) increased. QERB values were not systematically dependent on criterion. For low L2s, tip-to-tail differences decreased as criterion increased. Given similarities in methodology, DPOAE STCs constructed from completely suppressed responses might be most appropriate for comparison to psychophysical tuning curves. 2004 Acoustical Society of America. [ABSTRACT FROM AUTHOR]

The article reports on developments related to acoustics standards as of November 2004. Accredited Standards Committees S2, Mechanical Vibration and Shock, and S3, Bioacoustics approved ballots authorizing changes in their scopes in the United States. The primary responsibility for the working group (WG 39) will be transferred from S3 to S2.

Presents information on the events held by several acoustical associations in the U.S. from 2003 to 2004. Outcome of the meetings held by the Acoustical Oceanography in 2003; Sessions held by Animal Bioacoustics; Number of people who attended the Technical Committee meeting of the Techical Committee on Architectural Acoustics.

The article reports on the American Acoustical Society's publication of the American National Standards developed by the Accredited Standards Committees in the areas of acoustics, mechanical vibration and shock, bioacoustics and noise. The society has also published Catalogs of Acoustical Standards.

Detailed acoustic surveys of benthic sediments were conducted in July 1995 and September 1998 in the vicinity of Humboldt Bay, California. During these surveys, a band of enhanced acoustic backscatter was observed offshore from the bay entrance, approximately parallel to the isobaths, in water depths ranging from 16-24 m. In order to assess the cause of the increase in backscatter levels, a more comprehensive study was conducted in August and September 1999 using 100 kHz side-scan sonar, bottom grab sampling and underwater video recording. New observations indicated that a dense population of sand dollars (Dendraster excentricus) coincided with the enhanced backscatter band. Compared to the two previous acoustic studies, the central section of the band expanded westward by 180 m and the southern section of the band shifted eastward by 160 m, possibly resulting from a change in the biological or physical factors which influence the location and breadth of sand dollars. The relationship between high sand dollar abundance and enhanced acoustic backscatter was further verified in the nearshore region off Samoa Beach California, where a dense, banded population of sand dollars was previously observed. Video footage confirmed the presence of a band of sand dollars, also nominally parallel to the isobaths, in water depths of 8–15 m. A band of enhanced backscatter coincided with the dense sand dollar population. The identification of dense aggregations of sand dollars through enhanced acoustic backscatter could lead to the use of acoustic techniques to study sand dollar distributions and abundance. [ABSTRACT FROM AUTHOR]

A vocalization of the ringtailed lemur (Lemur catta) was examined for individual differences according to several temporal- and frequency-dependent variables. Vocalizations were tape recorded at the Duke University Primate Center (Durham, NC) and spectrographically analyzed. Significant differences were found in pair-wise comparisons of call structure among the study subjects, thus providing the physical basis for individual discrimination. A separate analysis comparing degree of kinship and vocal similarity revealed a positive but nonsignificant correlation between these two variables. This study represents an initial examination of vocal individuality in prosimian primates. [ABSTRACT FROM AUTHOR]

Acoustic recordings of soundscapes are an important category of audio data that can be useful for answering a variety of questions, and an entire discipline within ecology, dubbed "soundscape ecology," has risen to study them. Bird sound is often the focus of studies of soundscapes due to the ubiquitousness of birds in most terrestrial environments and their high vocal activity. Autonomous acoustic recorders have increased the quantity and availability of recordings of natural soundscapes while mitigating the impact of human observers on community behavior. However, such recordings are of little use without analysis of the sounds they contain. Manual analysis currently stands as the best means of processing this form of data for use in certain applications within soundscape ecology, but it is a laborious task, sometimes requiring many hours of human review to process comparatively few hours of recording. For this reason, few annotated data sets of soundscape recordings are publicly available. Further still, there are no publicly available strongly labeled soundscape recordings of bird sounds that contain information on timing, frequency, and species. Therefore, we present the first data set of strongly labeled bird sound soundscape recordings under free use license. These data were collected in the Northeastern United States at Powdermill Nature Reserve, Rector, Pennsylvania, USA. Recordings encompass 385 minutes of dawn chorus recordings collected by autonomous acoustic recorders between the months of April through July 2018. Recordings were collected in continuous bouts on four days during the study period and contain 48 species and 16,052 annotations. Applications of this data set may be numerous and include the training, validation, and testing of certain advanced machine-learning models that detect or classify bird sounds. There are no copyright or propriety restrictions; please cite this paper when using materials within., (© 2021 The Authors. Ecology © 2021 The Ecological Society of America.)

The article reports on the importance of otoacoustic emissions in testing the hearing of newborn infants, based on the study of researchers from the University of Michigan and Oregon Health and Science University in the U.S. Karl Grosh, a professor in the University of Michigan departments of Mechanical Engineering and Biomedical Engineering, explained that they will develop tools to determine the cause of hearing damage of infants. Tianying Ren, associate professor at the Oregon Health, showed that the sound waves travel through the fluid of the inner ear rather than rippling along the basilar membrane of the cochlea.

The world's first antenna that mimics the hearing mechanism of insects has been unveiled by researchers at the University of Wisconsin in the US. Dr Nader Behdad tells us more. [ABSTRACT FROM AUTHOR]

The article offers acoustical news briefs from United States of America. The photographs of the fellows of the Acoustical Society of America including Sergio Beristain, David R. Palmer, Mark V. Trevorrow and Michael Vorlander are published. A report on the 27th F. V. Hunt Postdoctoral Fellow (2005 - 2006) was published. A calendar of meetings related to acoustics to be held in United States in the near future is also presented.

The article reports on the observance of the Better Hearing and Speech Month in the U.S. in May 2008. As reported, failure to diagnose hearing loss at an early age may result to delay in speech, language, social skills and academic achievement. Measures to be done once hearing loss is confirmed are suggested. Additional information is available from the Web site of the Centers for Disease and Control Prevention (CDC).