Bioacoustics
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Bioacoustics: Listening to Biodiversity, Wildlife, and Ecosystem Change
Bioacoustics is the study and application of biological sound. It includes research into how animals produce, transmit, receive, and interpret sound, as well as the use of recordings to detect species, monitor populations, study behavior, evaluate habitats, and measure ecological change. As recording equipment has become cheaper and computational analysis more powerful, bioacoustics has expanded from the detailed study of individual animal calls into a major tool for biodiversity science and conservation.
A central development has been passive acoustic monitoring, in which autonomous recorders are placed in an environment and left to collect sound for hours, months, or even years. These devices can continuously document birds, bats, frogs, insects, marine mammals, fish, and other sound-producing organisms without requiring researchers to remain in the field. Acoustic monitoring can therefore reveal animals that are nocturnal, cryptic, rare, migratory, underwater, or otherwise difficult to observe directly.
Modern bioacoustics increasingly combines these enormous recording archives with machine learning and artificial intelligence. Automated systems can search thousands of hours of sound for particular calls, distinguish species, estimate calling activity, identify individuals, and sometimes detect ecological patterns that would be impractical to measure manually.
Bioacoustics as a Tool for Biodiversity Monitoring
Conservation bioacoustics has become an important method for documenting where species occur and how biological communities change through time. Autonomous recorders can repeatedly sample the same locations using standardized methods, creating permanent records that researchers can revisit as analytical techniques improve.
Large acoustic-monitoring networks increasingly allow scientists to study biodiversity at landscape, national, and potentially continental scales. Networks of recorders can reveal migration timing, seasonal activity, changes in species distributions, responses to weather, and differences among habitats. Because recording stations can operate simultaneously across many locations, acoustic monitoring can capture ecological variation that would be difficult to document through traditional field surveys alone.
Researchers have applied passive acoustic monitoring to forests, farms, wetlands, grasslands, tropical ecosystems, cities, coral reefs, mangroves, oceans, caves, protected areas, and restoration sites. Acoustic observations are also increasingly combined with satellite imagery, camera traps, field surveys, environmental measurements, citizen science, and other biodiversity data.
Bioacoustics does not detect every species equally. Animals must produce detectable sounds, and the probability of detection depends on factors such as distance, vegetation, weather, background noise, microphone placement, recorder quality, call frequency, season, and animal behavior. Acoustic surveys therefore work best when their limitations are explicitly considered and, where necessary, when they are combined with complementary monitoring methods.
Artificial Intelligence and Automated Species Recognition
The enormous volume of data produced by autonomous recorders has made automated analysis one of the most important areas of modern bioacoustics.
Machine-learning systems can transform recordings into spectrograms and search them for recognizable acoustic patterns. Deep neural networks and other classification techniques can identify birds, bats, frogs, whales, dolphins, insects, and many other organisms from their vocalizations or other sounds.
BirdNET has become an influential example of this approach. Deep-learning systems trained on large collections of bird recordings can identify hundreds or thousands of species in complex natural soundscapes. Similar approaches are increasingly being developed for frogs, bats, marine mammals, insects, and other wildlife.
Researchers are also exploring transfer learning, self-supervised learning, computer-vision techniques applied to spectrograms, acoustic embeddings, few-shot learning, convolutional neural networks, random forests, and explainable artificial intelligence. These methods can reduce the amount of labeled data necessary to develop new classifiers and potentially allow models trained on one group of sounds to assist with recognition of entirely different species.
Artificial intelligence can dramatically accelerate acoustic analysis, but automated identification is not automatically reliable. Performance can vary among species, regions, habitats, microphones, and recording conditions. False positives and missed detections can produce misleading ecological conclusions unless classifiers are carefully validated.
Quality assurance, representative training datasets, standardized testing, and transparent reporting of classification errors are therefore essential when automated acoustic detections are used for conservation decisions.
Birds and Acoustic Monitoring
Birds are among the most extensively studied organisms in bioacoustics because vocalizations play such an important role in territorial behavior, mating, migration, social interaction, and species recognition.
Passive recorders can identify bird communities without requiring observers to be physically present during every survey. In some environments, autonomous recorders can detect as many or more species than traditional point counts, particularly when recordings cover long periods of the day or night.
Acoustic monitoring is especially valuable for nocturnal, migratory, rare, and secretive birds. Nocturnal flight calls can reveal migration routes and responses to environmental conditions. Acoustic systems have been used to monitor endangered Hawaiian birds, Northern Spotted Owls, Marbled Murrelets, thrushes, warblers, cuckoos, penguins, and many other species.
Birdsong also provides information beyond simple presence or absence. Researchers study variation in song structure, singing schedules, individual identity, population differences, territorial interactions, cultural transmission, habitat effects, environmental noise, and social behavior.
Large citizen-science projects are increasingly intersecting with acoustic monitoring. Applications capable of identifying birds from recordings can connect individual observations with large biodiversity databases, potentially creating extensive information about where and when species are detected.
Bats and Ultrasonic Bioacoustics
Bats represent another major field of acoustic monitoring. Most insect-eating bats navigate and hunt using ultrasonic echolocation, producing signals above the normal range of human hearing.
Electronic bat detectors convert or record these ultrasonic signals, allowing researchers to document activity without capturing or observing the animals directly. Acoustic characteristics such as frequency, duration, call shape, and pulse structure can sometimes distinguish species or groups of species.
Regional reference libraries are important because bat calls can vary geographically and because closely related species may produce overlapping signals. Researchers have developed acoustic libraries for bats in locations including Argentina, Malta, Algeria, Mexico, Chile, Brazil, and Central Africa.
Machine learning is increasingly used to classify bat calls automatically. Deep convolutional networks, random forests, geometric analysis of call shapes, and hybrid classification systems have all been explored.
Acoustic monitoring and traditional capture methods such as mist nets often detect different portions of a bat community. Consequently, several studies indicate that integrating acoustic methods with physical surveys can provide a more complete picture of bat biodiversity than either technique alone.
New approaches include remote monitoring of caves and even ultrasonic detectors mounted on small drones, potentially allowing researchers to investigate bat activity vertically as well as horizontally across landscapes.
Amphibians and Calling Communities
Frogs and other vocal amphibians are particularly suitable for passive acoustic monitoring because males of many species produce distinctive advertisement calls during breeding.
Long-term recordings can document breeding seasons, calling intensity, daily activity, population presence, and environmental influences on reproductive behavior. Temperature, rainfall, photoperiod, and other environmental factors can strongly influence when amphibians call.
Acoustic monitoring has helped researchers rediscover rare frogs that were difficult to locate through conventional field surveys. It has also been used to monitor threatened populations and investigate potential responses to climate change.
Researchers are developing increasingly sophisticated automated systems for identifying frog calls. These include denoising, call segmentation, machine learning, deep learning, transfer learning, and few-shot recognition.
Bioacoustics also continues to reveal previously unknown aspects of amphibian biology. Species and even entire groups historically considered largely silent have been found to produce structured sounds.
Human-generated noise can interfere with amphibian communication. Studies indicate that traffic and urban noise can alter calling behavior, mating interactions, physiology, and potentially reproductive success.
Whales, Dolphins, and Marine Mammals
Sound is especially important in the ocean because light penetrates only limited distances while sound can travel far underwater. Marine mammals therefore rely heavily on acoustic communication and echolocation.
Hydrophones allow researchers to monitor whales, dolphins, and porpoises continuously without seeing the animals. Passive acoustic networks have been used to document sperm whales, right whales, humpback whales, blue whales, fin whales, minke whales, killer whales, belugas, bottlenose dolphins, harbor porpoises, and numerous other cetaceans.
Recordings can reveal migration, habitat use, feeding activity, social communication, individual identity, population-specific vocal traditions, and responses to environmental change.
Some acoustic systems are moving toward near-real-time detection. Endangered North Atlantic right whales and Mediterranean sperm whales, for example, can potentially be detected acoustically quickly enough for information to contribute to vessel-management and collision-reduction efforts.
Machine learning is also beginning to move marine bioacoustics beyond simple presence detection. Researchers have combined acoustic detections with aerial surveys and other data in attempts to estimate whale abundance.
Long-term whale recordings can contain ecological information as well. Changes in singing activity may correspond with prey availability or environmental conditions, although acoustic activity must be interpreted carefully because the amount an animal vocalizes is not necessarily proportional to the number of animals present.
Animal Communication and Individual Identity
Bioacoustics is not limited to monitoring biodiversity. It remains a fundamental method for studying animal communication.
Researchers analyze how calls convey information about identity, reproductive condition, motivation, aggression, age, body size, social relationships, territorial status, and environmental context.
Some animals produce individually recognizable vocalizations. Signature whistles in dolphins, vocal characteristics in penguins, distinctive leopard calls, and other individual acoustic signatures raise the possibility of identifying particular animals without physically capturing or marking them.
Acoustic studies can also reveal cultural variation. Bird songs and whale call repertoires can differ among populations and change through learning and social transmission.
Long-term acoustic archives therefore provide researchers with a way to examine not only ecological change but also the persistence and evolution of animal communication traditions.
Insects and Other Invertebrates
Bioacoustic monitoring is increasingly expanding beyond vertebrates.
Crickets, grasshoppers, bees, flies, water bugs, and many other invertebrates produce detectable sounds or vibrations associated with movement, feeding, courtship, territorial behavior, and communication.
Improvements in microphones, autonomous recorders, and automated recognition systems are making large-scale insect acoustic monitoring increasingly practical. This could be especially important because insects are extraordinarily diverse while long-term population monitoring remains limited for many groups.
Researchers have examined tropical insect soundscapes, grasshopper and cricket monitoring, bee flight buzzing, floral sonication vibrations, fruit-fly courtship songs, and underwater sounds made by aquatic insects.
Bioacoustic sensors combined with artificial intelligence may also have applications in agriculture. Automated systems could potentially detect pest species through sounds produced during feeding, movement, flight, or communication, enabling continuous monitoring while reducing dependence on labor-intensive manual inspections.
Soundscapes and Ecosystem Health
Ecoacoustics expands the focus from individual species to entire acoustic environments.
A soundscape consists of biological sounds, environmental sounds, and sounds generated by human activity. Birds, insects, frogs, mammals, fish, wind, rain, waves, vehicles, aircraft, machinery, and other sources can all contribute to the acoustic character of an ecosystem.
Researchers increasingly investigate whether changes in soundscapes can reveal changes in biodiversity or ecological condition.
Soundscape monitoring has been applied to tropical forests, agricultural landscapes, cities, soil ecosystems, reefs, mangroves, temperate marine habitats, and restoration projects.
Because autonomous recorders can collect standardized data repeatedly, soundscapes may provide a relatively inexpensive way to track ecological change across large areas and long periods.
However, soundscape measurements require careful interpretation. A louder or more acoustically complex environment does not necessarily contain more species. Weather, human activity, recorder design, animal behavior, and a small number of especially vocal species can substantially influence acoustic measurements.
Acoustic Indices and Measuring Biodiversity
Researchers have developed numerical acoustic indices intended to summarize complex recordings.
These measurements can describe properties such as acoustic complexity, frequency occupancy, temporal variation, or the distribution of acoustic energy. In principle, they offer an attractive way to process enormous datasets without manually identifying every sound.
Results have been mixed.
Some studies find relationships between acoustic indices and ecological characteristics, while others show that indices do not consistently predict species richness across unrelated ecosystems.
Recorder type, environmental noise, data compression, habitat structure, and sampling design can all alter index values. Consequently, acoustic indices should not automatically be interpreted as direct measurements of biodiversity.
Their strongest use may be in detecting changes within well-characterized environments where acoustic measurements have been calibrated against independent ecological observations.
Habitat Restoration and Conservation Management
One promising application of bioacoustics is evaluating whether ecological restoration actually produces biological recovery.
Recorders can be placed in degraded, recovering, and reference ecosystems to compare changes in birds, insects, frogs, bats, fish, and entire soundscapes.
Research in restored forests and mangroves has shown that acoustic communities can differ according to habitat age and structural complexity. Recorders have also been deployed before and after wildlife reintroductions to determine whether released animals establish populations.
Coral-reef restoration provides another example. Underwater soundscapes can change as reef communities recover, although different analytical methods may produce different estimates of the pace or magnitude of recovery.
Bioacoustics therefore offers conservation managers a potentially scalable method of repeatedly measuring restoration outcomes without requiring continuous human surveys.
Human Noise and Wildlife
Human-generated sound has become a major subject of bioacoustic research.
Traffic, ships, industrial activity, aircraft, machinery, artificial infrastructure, and other sources can interfere with animal communication by masking biologically important signals.
Animals may respond by altering the pitch, timing, duration, intensity, or frequency of their calls. Noise can also change territorial behavior, vigilance, feeding efficiency, mating behavior, and habitat use.
Studies of birds, frogs, whales, dolphins, and other animals demonstrate that acoustic pollution can affect wildlife even when populations appear otherwise intact.
Passive acoustic monitoring can document both biological sounds and anthropogenic noise simultaneously. This makes it possible to measure how sound-producing animals respond as human acoustic disturbance changes through time.
Monitoring Rare and Endangered Species
Bioacoustics can be especially useful for species that are difficult to observe.
Rare animals may occur at densities too low for conventional surveys. Nocturnal species may be active when visual observation is difficult. Forest vegetation can conceal animals only meters away, while marine species may spend most of their lives underwater.
If these animals vocalize, autonomous recording devices can continuously search for evidence of their presence.
Acoustic monitoring has been applied to endangered whales, threatened forest birds, rare frogs, gibbons, wolves, elephants, bats, and many other conservation-sensitive species.
Automated classifiers can further increase monitoring capacity by searching enormous datasets for rare calls. Nevertheless, detections of highly consequential species require careful validation because even low false-positive rates can produce large numbers of errors when millions of acoustic events are processed.
From Recorders to Continental Monitoring Networks
Bioacoustic monitoring is gradually increasing in scale.
Early projects often involved researchers placing a small number of microphones at individual study sites. Modern programs may deploy hundreds or thousands of autonomous recorders across forests, countries, or large ecological regions.
Edge computing may eventually allow recorders to analyze sounds locally rather than transmitting every recording to centralized servers. Solar power, inexpensive electronics, wireless communications, open-source hardware, and citizen-science participation may further reduce the cost of maintaining large monitoring networks.
Existing infrastructure may sometimes serve multiple purposes. Underwater telemetry systems, for example, may also record environmental sound that can provide information about marine ecosystems.
At the largest scale, coordinated acoustic networks could contribute to national and international biodiversity monitoring by documenting changes in animal distributions, migration, phenology, ecosystem condition, and human disturbance.
Challenges and Limitations
Despite its rapid development, bioacoustics has important limitations.
Not all animals vocalize frequently enough to be detected reliably. Calling behavior can change with season, time of day, weather, breeding status, population density, disturbance, and social context.
Sound propagation also varies. Vegetation, terrain, water depth, atmospheric conditions, microphone height, recording equipment, and the frequency of the signal all influence detection range.
Automated classifiers introduce additional uncertainty. Systems trained in one environment may perform poorly in another. Background sounds may resemble target calls, while overlapping signals can conceal real vocalizations.
Data storage is another challenge. Continuous high-quality recordings from thousands of sensors can generate enormous datasets. Compressing audio reduces storage requirements but may remove information and reduce the accuracy of both automated classifiers and human listeners.
Standardization remains important. Differences in equipment, sampling schedules, file formats, annotation practices, classifier thresholds, and analytical methods can make comparisons among projects difficult.
Bioacoustics should therefore be viewed as a powerful component of biodiversity monitoring rather than a universal replacement for field ecology.
The Future of Conservation Bioacoustics
The future of bioacoustics is increasingly connected with artificial intelligence, inexpensive sensors, open datasets, citizen science, satellite observations, ecological modeling, and large distributed monitoring networks.
Improved machine-learning systems may eventually identify enormous numbers of species from sound while simultaneously detecting previously unknown acoustic patterns.
Transfer learning and foundation models could make it easier to develop monitoring systems for poorly studied species with limited training data. Explainable artificial intelligence may help researchers understand why models classify particular sounds and identify conditions under which predictions become unreliable.
Real-time acoustic systems could also become more important. Instead of collecting recordings that are analyzed months later, sensors may detect endangered animals, invasive species, ecological disturbances, or illegal activities quickly enough to support immediate management responses.
At the same time, researchers are increasingly emphasizing that technological sophistication does not eliminate the need for ecological knowledge. Automated detections must still be interpreted in the context of animal behavior, habitat, environmental conditions, sampling design, and conservation objectives.
Conclusion
Bioacoustics has developed from the study of individual animal sounds into a broad scientific toolkit for understanding biodiversity and environmental change.
Autonomous recorders can listen continuously in forests, farms, cities, caves, wetlands, oceans, and restoration sites. Artificial intelligence can search these recordings for species and ecological patterns at scales that were previously impossible. Birds, bats, frogs, whales, dolphins, insects, fish, terrestrial mammals, and even soil communities can increasingly be investigated through the sounds they produce.
The greatest strength of bioacoustics is its ability to create permanent, repeatable records of biological activity while minimizing disturbance to wildlife. These archives can reveal species presence, migration, behavior, ecosystem recovery, human disturbance, and changes that unfold over years or decades.
Its limitations are equally important. Acoustic activity is not identical to biodiversity, automated classifications can be wrong, and environmental conditions strongly influence what microphones detect.
Used carefully and combined with field ecology, remote sensing, citizen science, and other monitoring methods, conservation bioacoustics offers one of the most promising ways to listen to ecological change across the planet.
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General Conservation, Soundscapes & Ecosystem Monitoring
Listening Forward: Emerging Roles of Bioacoustics in Ecology, Evolution, and Conservation
| Sándor Zsebők | Biologia Futura | 2026-06-09
Advances in autonomous recorders, machine learning, transfer learning, edge computing, and explainable AI are changing bioacoustics from a largely descriptive science into a powerful tool for predicting ecological change and studying animal communication.
The Role of Conservation Bioacoustics in Achieving Global Biodiversity Goals
| Multiple authors | Nature Reviews Biodiversity | 2026
Conservation bioacoustics is emerging as an important tool for measuring species distributions, ecosystem change, restoration outcomes, and human impacts. The review examines passive acoustic monitoring, machine learning, occupancy modeling, soundscapes, and the growing role of acoustic data in meeting global biodiversity conservation targets.
Suggestions for Extending, Expanding, and Integrating Passive Acoustic Monitoring Programs
| Multiple authors | Ecological Indicators | 2026
Long-term acoustic monitoring programs can become more valuable when recording hardware, data storage, staffing, analysis pipelines, and collaboration are planned from the beginning for expansion across larger areas and additional species.
Acoustic Recordings from Narrow-Band Telemetry Arrays Allow Long-Term Monitoring of the Marine Ecological State
| Multiple authors | Ecological Informatics | 2026
Researchers show that underwater acoustic telemetry infrastructure can also collect environmental sound useful for detecting changes in marine biological activity, potentially turning existing telemetry networks into economical long-term ecosystem-monitoring systems.
Predicting the Ecological Condition of Grazed Australian Landscapes Using Passive Acoustic Monitoring
| Multiple authors | Ecological Indicators | 2026
Researchers combine satellite observations, landscape metrics, bird data, and passive acoustic monitoring to develop a scalable method for measuring ecological condition across large agricultural landscapes.
The Role of Ecoacoustics in Monitoring Ecosystem Degradation and Restoration
| Multiple authors | Restoration Ecology | 2025-08-13
Researchers review how soundscapes can provide relatively inexpensive and repeatable measurements of ecological degradation and recovery while discussing limitations involving interpretation, standardization, and environmental noise.
Zoo Soundscapes Could Be a New Frontier in Bioacoustics Studies
| International Centre for Zoo Science - Chester Zoo | Phys.org | 2025-07-16
Researchers argue that zoos offer valuable controlled environments for studying animal vocalizations, soundscapes, welfare, communication, and conservation questions while building reference recordings useful for field research.
Human Contributions to Global Soundscapes Are Less Predictable Than the Acoustic Rhythms of Wildlife
| Panu Somervuo et al. | Nature Ecology & Evolution | 2025-07-09
A global analysis of soundscapes finds that wildlife often follows strong daily acoustic rhythms while human-generated sounds are more irregular, helping distinguish biological and anthropogenic components of acoustic environments.
Sensors Versus Surveyors: Comparing Passive Acoustic Monitoring, Camera Trapping and Observer-Based Monitoring for Terrestrial Mammals
| Sebastian Hoefer et al. | Methods in Ecology and Evolution | 2025
The study compares acoustic recorders, camera traps, and human surveys for terrestrial mammals, addressing how remote monitoring technologies differ in species detection and their usefulness for large-scale conservation.
The Potential of Soundscapes as an Ecosystem Monitoring Tool for Urban Biodiversity
| Multiple authors | Journal of Urban Ecology | 2025
The review examines how soundscape ecology could help monitor biodiversity in cities while emphasizing challenges created by traffic, machinery, human activity, analytical bias, and the difficulty of interpreting acoustic indices.
Integrating Soundscape to Landscape in the Understanding of Agricultural Transformation in the Neotropical Context
| Angela M. Mendoza-Henao et al. | Philosophical Transactions of the Royal Society B | 2025
Researchers connect acoustic measurements with landscape characteristics to investigate how agricultural transformation changes the biological soundscape of tropical environments.
Tuning into Nature: The Sonic Boost Transforming Tropical Biodiversity Research
The authors examine the rapid expansion of tropical bioacoustics and argue that autonomous recorders, open datasets, artificial intelligence, and regional collaborations can transform biodiversity research in species-rich tropical ecosystems.
Wild Frequencies: Podcast Miniseries from India Explores Wild Animal Sounds
| Mongabay.com | Mongabay | 2024-12-30
This overview of the Wild Frequencies series introduces field researchers using bioacoustics across forests, grasslands, and cities in India to study animals that range from large mammals to insects.
An Inventory for Acoustic Monitoring: Interview with Kevin Darras
| Abhishyant Kidangoor | Mongabay | 2024-10-05
The Worldwide Soundscapes initiative is assembling information about where, when, and how biodiversity acoustic monitoring occurs globally to encourage data sharing, collaboration, and large-scale ecological analysis.
Wild Frequencies: Us and Them
| Shreya Dasgupta & Kartik Chandramouli | Mongabay India | 2024-08-01
Changes in the frequency, timing, pitch, and occurrence of animal calls can reveal how birds, mammals, and insects respond to urbanization, infrastructure, agriculture, and other human modifications of landscapes.
Wild Frequencies: Know Them
| Shreya Dasgupta & Kartik Chandramouli | Mongabay India | 2024-07-25
Bioacoustic researchers examine calls in behavioral context to investigate how animals communicate about mating, danger, social relationships, and other aspects of their lives.
Wild Frequencies: Find Them
| Shreya Dasgupta & Kartik Chandramouli | Mongabay India | 2024-07-18
Researchers explain how animal sounds ranging from bird calls to ultrasonic bat signals can reveal the presence of wildlife that may be extremely difficult to detect visually.
Counting the Chorus: A Bioacoustic Indicator of Population Density
| Multiple authors | Ecological Indicators | 2024
Researchers found that the density of detected calls can correlate with independently estimated animal density, suggesting a potentially scalable way to convert acoustic detections into measures useful for wildlife population management.
The Efficacy of Acoustic Indices for Monitoring Abundance and Diversity in Soil Soundscapes
| Multiple authors | Ecological Indicators | 2024
Researchers test whether commonly used acoustic indices can measure the abundance and diversity of sound-producing soil organisms, extending ecoacoustics below ground.
Passive Acoustic Monitoring in Terrestrial Vertebrates: A Review
| Sebastian Hoefer et al. | Bioacoustics | 2023
A review comparing passive acoustic monitoring with observer-based surveys found that acoustic methods often performed similarly or better for vocal terrestrial vertebrates while emphasizing the need to combine methods for quiet species.
Passive Acoustic Monitoring Provides a Fresh Perspective on Fundamental Ecological Questions
| Samuel R. P.-J. Ross et al. | Functional Ecology | 2023
The review argues that passive acoustics can address fundamental ecological questions involving biodiversity, population trends, phenology, species distributions, disturbance, recovery, and ecological processes across large spatial and temporal scales.
Using Passive Acoustic Monitoring to Examine the Impacts of Ecological Restoration on Faunal Biodiversity in the Western Ghats
| Multiple authors | Biological Conservation | 2023
Recordings along a forest-restoration gradient in India detected differences among birds, insects, and other vocal animals, demonstrating how acoustic monitoring can evaluate recovery across several faunal groups simultaneously.
What Conservation Sounds Like
| Living Bird Staff | All About Birds | 2023
This overview explores how modern conservation bioacoustics is used to monitor owls, whales, insects, fish, forest biodiversity, illegal logging, and many other conservation problems as cheap recorders and automated recognizers become widely available.
Exploring Spatio-Temporal Variation in Soundscape Saturation of an African Tropical Forest Landscape
| Multiple authors | Ecological Indicators | 2022
Long-term recordings reveal how the amount and timing of biological sound vary across tropical forest habitats, helping researchers understand when acoustic communities become crowded with overlapping signals.
Terrestrial Passive Acoustic Monitoring: Review and Perspectives
| Larissa Sayuri Moreira Sugai et al. | BioScience / BioAcoustica | 2019
A systematic review of hundreds of terrestrial acoustic studies documented rapid growth in the field while identifying strong biases toward bats, temperate regions, nighttime monitoring, and manual analysis.
A Methodology for Analyzing Biological Choruses from Long-Term Passive Acoustic Monitoring in Natural Areas
| Multiple authors | Ecological Informatics | 2017
Researchers develop analytical techniques for identifying recurring biological choruses in long-duration recordings, helping transform massive sound archives into ecologically meaningful temporal patterns.
AI, Analytics & Monitoring Methods
Harnessing Edge Computing and Citizen Science: A New Prototype Design for Continental-Scale Acoustic Monitoring
| Andrea S. Griffin et al. | Methods in Ecology and Evolution | 2026-06-16
Researchers propose combining low-cost recorders, edge computing, open-source tools, and citizen participation to make continental-scale biodiversity monitoring more technically and financially practical.
PNW-Cnet: An Evolving Convolutional Neural Network to Support Broad-Scale Passive Acoustic Monitoring
| Multiple authors | Ecological Informatics | 2026
PNW-Cnet uses deep learning to identify more than 100 wildlife species and sound types from massive passive-acoustic datasets. The system is designed for broad-scale biodiversity monitoring and includes techniques for improving detection of rare calls.
Promise and Pitfalls: Variable Performance of AI-Assisted Passive Acoustic Monitoring of Birds and Frogs Using BirdNET and VicFrogNET
| Multiple authors | Ecological Informatics | 2026
Researchers evaluate automated acoustic-identification systems for birds and frogs and find that performance can vary substantially among species, habitats, and recording conditions, emphasizing the importance of validating AI detections before using them for ecological inference.
BioSoundSCape: A Bioacoustic Dataset for the Fynbos Biome
| Andrew A. Turner et al. | Scientific Data | 2025-08-15
Recordings from hundreds of sites across South Africa's Fynbos biome create a large standardized acoustic dataset that can support research on biodiversity, ecological change, species recognition, and soundscape ecology.
The MAMBAT Framework for Acoustic Tracking of Multiple Animals
| Pina Gruden, Eva-Marie Nosal & E. Elizabeth Henderson | Scientific Reports | 2025-05-13
The MAMBAT framework estimates the locations and movement of multiple simultaneously vocalizing animals from microphone-array recordings, expanding the potential of bioacoustics for behavioral and spatial ecology.
The Use of BirdNET Embeddings as a Fast Solution to Find Novel Sound Classes in Audio Recordings
Instead of using BirdNET only to identify known birds, researchers use its internal acoustic representations to search recordings for previously unlabeled sounds, potentially making large sound archives easier to explore.
Using Tropical Reef, Bird and Unrelated Sounds for Superior Transfer Learning in Marine Bioacoustics
| Ben Williams et al. | Philosophical Transactions of the Royal Society B | 2025
Machine-learning models pretrained on large acoustic datasets—including sounds outside the marine environment—can improve recognition of underwater biological sounds, demonstrating the value of transfer learning in marine bioacoustics.
Birds, Bats and Beyond: Evaluating Generalization in Bioacoustics Models
Researchers examine whether machine-learning representations trained on some animal sounds can generalize to new taxa and recording tasks, an important question for developing broadly useful foundation models for bioacoustics.
All Thresholds Barred: Direct Estimation of Call Density in Bioacoustic Data
Researchers develop an approach for estimating calling activity directly from classifier predictions without relying on a single arbitrary detection threshold, potentially improving quantitative analysis of automated acoustic surveys.
Advancements in Preprocessing, Detection and Classification Techniques for Ecoacoustic Data
| Thomas Napier et al. | Expert Systems with Applications | 2024
This review examines datasets, noise reduction, event detection, classification, machine learning, and analytical frameworks for processing the enormous amounts of data created by large passive-acoustic monitoring programs.
Parselmouth for Bioacoustics: Automated Acoustic Analysis in Python
| Yannick Jadoul, Bart de Boer & Andrea Ravignani | Bioacoustics | 2024
Parselmouth allows Python programs to use the acoustic-analysis capabilities of Praat, making it easier for researchers to automate measurements and process large collections of animal recordings.
Efficient Quality Assurance and Quality Control for Passive Acoustic Monitoring Data: Reducing and Documenting False-Positive and False-Negative Errors
| Janine M. McManus, Barry G. Robinson & Steven L. Van Wilgenburg | Bioacoustics | 2024
The authors present procedures for validating automated acoustic detections and documenting classification errors so that large monitoring programs can produce defensible ecological results.
An Inadequate Sampling of the Soundscape Leads to Overoptimistic Estimates of Recogniser Performance: A Case Study of Two Sympatric Macaw Species
Acoustic classifiers can appear highly accurate when validation datasets fail to represent the full diversity of real-world background sounds, illustrating a major source of bias in automated wildlife recognition.
Passive Acoustic Monitoring of Animal Populations with Transfer Learning
| Multiple authors | Ecological Informatics | 2022
Researchers tested pretrained convolutional neural networks on wildlife recordings and found that transfer learning can produce useful acoustic classifiers even when only small numbers of verified animal calls are available.
Utility of Acoustic Indices for Ecological Monitoring in Complex Sonic Environments
| Multiple authors | Ecological Indicators | 2021
Acoustic indices are evaluated in environments containing complex combinations of biological, environmental, and human sounds, illustrating why index values cannot always be interpreted as straightforward biodiversity measurements.
Sound Finder: A New Software Approach for Localizing Animals Recorded with a Microphone Array
| David R. Wilson, Matthew Battiston, John Brzustowski & Daniel J. Mennill | Bioacoustics | 2014
Sound Finder software calculates the positions of vocalizing animals from the arrival times of sounds at multiple microphones, making spatial acoustic analysis more accessible to behavioral researchers.
Real-Time Bioacoustics Monitoring and Automated Species Identification
| T. Mitchell Aide et al. | PeerJ | 2013
The ARBIMON project demonstrated an early integrated system in which solar-powered remote stations automatically collected, transmitted, stored, visualized, and analyzed wildlife sounds from tropical ecosystems using machine-learning species detectors.
Acoustic Monitoring in Terrestrial Environments Using Microphone Arrays
| Daniel T. Blumstein et al. | Journal of Applied Ecology | 2011
This influential review explains how microphone arrays can record and locate calling animals, allowing researchers to study spatial behavior, communication, abundance, and interactions without continuously observing the animals themselves.
A Field Test of the Accuracy of a Passive Acoustic Location System
| J. L. Bower & C. W. Clark | Bioacoustics | 2005
A microphone-array system was tested for locating calling birds in the field and achieved high positional accuracy when animals vocalized within or near the recording array, demonstrating the potential of acoustics for spatial wildlife studies.
Birds
Birdsong Data from Merlin ID App to Help Global Biodiversity Project
| Sandra Laville | The Guardian | 2026-07-04
Cornell's Merlin bird-identification app is expanding the conservation value of automated birdsong recognition by connecting acoustic identifications with large citizen-science biodiversity datasets.
Scientist Wins Prize for Decoding Birdsong
| Multiple contributors | The Guardian | 2026-06-26
Machine learning is accelerating research into the structure and possible meaning of animal vocalizations, including birds and primates, while scientists caution that decoding calls remains very different from achieving true two-way communication.
Forest Type Consistently Shapes Bird Communities Across Seasons: Insights from Passive Acoustic Monitoring
Passive acoustic monitoring reveals persistent differences in bird communities among forest types across seasons, demonstrating how autonomous recording can help evaluate forest-management effects on biodiversity.
National-Scale Acoustic Monitoring of Avian Biodiversity and Migration
| I. Avery Bick et al. | Communications Biology | 2026-05-30
A nationwide network of acoustic sensors in Norway collected more than 37,000 hours of recordings during spring migration, demonstrating how passive acoustics can reveal large-scale changes in bird diversity, migration timing, and responses to environmental conditions.
Bioacoustics Monitoring of Bird Vocal Behavior for Species Identification, Survey, and Habitat Impact
| Multiple authors | International Journal of Zoology | 2026
Bioacoustic surveys around Ethiopia's Lake Tana identified dozens of bird species across island, agricultural, grazing, and urban habitats and improved detection of cryptic and nocturnal species compared with traditional field observation alone.
Vocal Repertoire and Acoustic Cues to Individual Identity in the Northern Rockhopper Penguin
| Vittoria Turone et al. | Bioacoustics | 2026
Northern Rockhopper Penguins produce several distinct vocal types used during conflict, contact, territorial defense, and mate attraction, and the calls contain acoustic information capable of identifying individual birds.
Factors Affecting Acoustic Propagation of Birdsong in Bachman's Sparrow
| Hans R. Gonzembach, Heather Wolverton & Rindy C. Anderson | Bioacoustics | 2026
Experiments with Bachman's Sparrow songs investigate how habitat and song structure influence sound transmission, providing insight into how environments may shape the evolution and effectiveness of animal communication.
Effects of Different Anthropogenic Noise Levels on an Urban-Living Bird
| Grace Blackburn & Amanda R. Ridley | Bioacoustics | 2026
Research on Western Australian magpies shows that even intermediate levels of human-generated noise can alter wildlife behavior, including foraging efficiency, vigilance, and aspects of vocal activity.
Passive Acoustic Monitoring Predicts Higher Avian Diversity Metrics Than Traditional Bird Surveys Across Multiple Australian Bioregions
Comparisons across Australian landscapes show that passive acoustic surveys can detect greater bird diversity than conventional observer surveys, although differences in sampling effort and detection processes need to be considered.
Audubon Receives $2 Million to Harness AI for Bird Conservation in Latin America
| National Audubon Society | Audubon | 2025-10-26
Audubon plans to expand community-based acoustic monitoring in the Tropical Andes using autonomous recording units and artificial intelligence to track bird populations and habitat change.
Comparing Point Counts, Passive Acoustic Monitoring, Citizen Science and Machine Learning for Bird Species Monitoring in the Mount Kenya Ecosystem
| Ciira wa Maina & Peter Njoroge | Philosophical Transactions of the Royal Society B | 2025-06-12
Researchers compare several approaches to monitoring birds around Mount Kenya and examine how autonomous recordings, automated identification, field observations, and citizen-science data can complement one another.
Why Is the Early Bird Early? An Evaluation of Hypotheses for Avian Dawn-Biased Vocal Activity
| Multiple authors | Philosophical Transactions of the Royal Society B | 2025-06-12
Researchers use large acoustic datasets to investigate why birds concentrate singing around dawn and examine environmental, behavioral, and communication hypotheses for the widespread dawn chorus.
AI Uncovers How Birds Remix Their Songs Over Time
| Abhishyant Kidangoor | Mongabay | 2025-04-17
Artificial intelligence helped researchers analyze thousands of hours of Great Tit songs and investigate how age, dispersal, and population structure influence the persistence and spread of different song types.
Traffic Noise Turns Galápagos Warblers into Angry Birds
| Shreya Dasgupta | Mongabay | 2025-04-03
Playback experiments with Galápagos Yellow Warblers indicate that traffic noise can alter territorial behavior, illustrating how anthropogenic sound changes communication and social interactions even in relatively isolated ecosystems.
Acoustic Monitoring Network for Birds Enhances Forest Management
| Cornell Lab of Ornithology | Cornell Lab of Ornithology | 2025-03-11
More than 1,600 recording sites across millions of acres of Sierra Nevada forest generated hundreds of thousands of hours of bird sounds, allowing researchers to monitor indicator species and provide information relevant to forest management.
How to Tell if Mangrove Restoration Is Working? Listen to the Birds
| Carolyn Cowan | Mongabay | 2025-02-03
Bioacoustic monitoring in Malaysian mangroves found richer bird communities in older and structurally more complex forests, suggesting bird sound recordings could help measure biodiversity recovery during mangrove restoration.
Sounds That Matter: How Passive Acoustic Monitoring Transforms Science and Benefits the Community
| Juliana Londoño | Audubon | 2025-01-31
Community conservation partners in Colombia are using autonomous recorders and AI-assisted bird identification to monitor protected areas and build locally managed biodiversity datasets.
From Chirps to Insights: Measuring Biodiversity with Audubon's Bird-Friendliness Index
| National Audubon Society | Audubon | 2025
Audubon's Bird-Friendliness Index incorporates bird observations and acoustic monitoring to assess functional diversity and ecological condition rather than relying only on simple species counts.
Identification of Nocturnal Flight Calls of Bicknell's Thrush and Gray-Cheeked Thrush
| E. Brisson-Curadeau et al. | Bioacoustics | 2025
Researchers analyzed nocturnal migration calls to determine whether rare Bicknell's Thrushes could be distinguished acoustically from closely related Gray-cheeked Thrushes, potentially improving migration monitoring.
Singing Behaviour of the Western Bonelli's Warbler Correlates with Social Context and Environmental Factors
| Sandro Carlotti & Gilberto Pasinelli | Bioacoustics | 2025
Western Bonelli's Warblers modify singing activity and song characteristics according to pairing status, breeding stage, weather, and season, illustrating the ecological information contained in animal acoustic behavior.
Continuous Real-Time Acoustic Monitoring of Endangered Bird Species in Hawai‘i
| Multiple authors | Ecological Informatics | 2025
A solar-powered real-time monitoring system uses BirdNET models to detect endangered Hawaiian birds continuously and provide rapid information that can support wildlife protection and operational decisions.
Nocturnal Flight Call Monitoring Reveals Behavioral Alteration by Migratory Birds in Response to Artificial Light
| Multiple authors | Biological Conservation | 2025
More than 100,000 hours of migration recordings were used to investigate how artificial lighting changes nocturnal bird flight behavior, with results suggesting that lighting design can influence the magnitude of the disturbance.
Passive Acoustic Monitoring and Acoustic Indices Reveal Noise-Related Changes in Bird Vocalizations
| M. Briseño-Jaramillo et al. | Bioacoustics | 2025
Recordings from Mexican forests show that several bird species alter the frequency, duration, or rate of their calls as natural and anthropogenic noise increases, demonstrating how acoustic monitoring can measure behavioral responses to noise.
A Grassroots Effort to Re-Bird the Empty Forests of Aratanha, Brazil
| Cornell Lab of Ornithology | All About Birds | 2025
Autonomous acoustic recorders are being used before and after bird reintroductions in Brazilian forests to determine whether translocated birds establish populations and how the surrounding soundscape changes.
The Utility of Passive Acoustic Monitoring for Using Birds as Indicators of Sustainable Agricultural Management Practices
The study considers how autonomous bird recordings can help assess whether agricultural management practices maintain habitat quality and biodiversity while reducing the cost of repeated field surveys.
Using Acoustic Cameras to Study Vocal Mobbing Reveals the Importance of Learning in Juvenile Arabian Babblers
An acoustic-camera system helps identify which individual Arabian Babblers are vocalizing during mobbing events, revealing how young birds develop appropriate alarm behavior through experience.
The Impact of Vehicular Noise on Acoustic Indices within Simulated Bird Assemblage Soundscapes
| Rebecca L. Ducay & Brent S. Pease | Bioacoustics | 2024-04-16
Simulated bird communities were combined with vehicle noise to test how common acoustic indices respond to anthropogenic sound, highlighting the need to understand noise effects before treating indices as direct measures of biodiversity.
Detection Ranges of Forest Bird Vocalisations: Guidelines for Passive Acoustic Monitoring
| Dominika Winiarska, Paweł Szymański & Tomasz S. Osiejuk | Scientific Reports | 2024-01-09
Field experiments quantify how far different forest bird songs can be detected by autonomous recorders and show that frequency, vegetation, microphone characteristics, and sound amplitude influence detection distance.
Passive Acoustic Monitoring and Convolutional Neural Networks Facilitate Broadscale Monitoring of a Threatened Species
| Multiple authors | Ecological Indicators | 2024
Researchers developed a convolutional neural network for identifying Marbled Murrelet calls, demonstrating how automated acoustic monitoring can track rare and cryptic threatened species across large landscapes.
Summer Calling Activity Patterns of a Bird Assemblage in a Valdivian Temperate Rainforest
| Felipe N. Moreno-Gómez et al. | Bioacoustics | 2024
Passive acoustic monitoring in Chile's Valdivian rainforest found strong daily variation in bird vocal activity, including peaks around sunrise and sunset, information that can improve the timing and design of biodiversity surveys.
Common Cuckoo Vocalisations as an Indicator for Avian Diversity – A Study with Passive Acoustic Monitoring
| Multiple authors | Ecological Indicators | 2024
Common Cuckoo calls were associated with relatively diverse bird communities in agricultural landscapes, suggesting that easily detected vocal indicator species might complement broader automated biodiversity surveys.
Influence of Recording Devices and Environmental Noise on Acoustic Index Scores: Implications for Bird Sound-Based Assessments
| Multiple authors | Ecological Indicators | 2024
Acoustic-index values can change according to recorder characteristics and background noise as well as actual biodiversity, showing why comparisons among sites require consistent equipment and careful calibration.
Audio Data Compression Affects Acoustic Indices and Reduces Detections of Birds by Human Listening and Automated Recognisers
| Alexander G. MacPhail et al. | Bioacoustics | 2024
Compressing wildlife recordings to save storage space can remove acoustic information, reduce automated and human bird detections, and change soundscape indices, creating important tradeoffs for large monitoring programs.
Limits to the Accurate and Generalizable Use of Soundscapes to Monitor Biodiversity
| Sarab S. Sethi et al. | Nature Ecology & Evolution | 2023-07-31
Analysis of thousands of recordings found that common soundscape indices and models did not reliably predict bird species richness across unrelated ecosystems, although soundscape changes were useful indicators of changes within ecological communities.
Hard of Hearing: Effect of Distance and Experimental Noise on Mountain Chickadee Song Transmission
| C. L. Snell, M. W. Reudink & K. A. Otter | Bioacoustics | 2023
Playback experiments show how distance and background noise affect the transmission of Mountain Chickadee songs, illustrating how anthropogenic sound can reduce communication range.
The Relationship Between the Acoustic Complexity Index and Avian Species Richness and Diversity
| Jade Bateman & Antonio Uzal | Bioacoustics | 2022
A review of studies using the Acoustic Complexity Index found inconsistent relationships between the index and actual bird richness or diversity, emphasizing that acoustic indices must be calibrated and interpreted within particular ecosystems.
Higher-Pitched Song Towards the Coast Supports a Role for Selection in Ocean Noise Avoidance
| Matteo Sebastianelli, Daniel T. Blumstein & Alexander N. G. Kirschel | Bioacoustics | 2022
Geographic variation in bird song frequency near noisy coastal environments suggests that long-term exposure to low-frequency ocean noise may contribute to selection for higher-pitched signals.
BirdNET: A Deep Learning Solution for Avian Diversity Monitoring
| Stefan Kahl et al. | Ecological Informatics | 2021
BirdNET demonstrates that deep neural networks can identify hundreds of bird species in complex field recordings, providing one of the most influential examples of large-scale automated animal-sound recognition.
The Sounds Between the Strophes: Different Chiffchaff Taxa Perform Different Tret Calls in Their Song
| Vladimir Ivanitskii, Irina Ilina & Irina Marova | Bioacoustics | 2021
Detailed analysis of calls embedded within chiffchaff songs reveals consistent differences among taxa that may contribute useful information to studies of geographic variation and avian taxonomy.
Song Amplitude and Population Density in Two Sympatric Warblers
| A. S. Opaev & E. M. Shishkina | Bioacoustics | 2021
Researchers investigate whether birds alter song amplitude in response to the density of neighboring singers, contributing to understanding how social environments shape acoustic communication.
House Finches Learn Canary Trills
| Dan C. Mann, David C. Lahti, Laura Waddick & Paul C. Mundinger | Bioacoustics | 2021
Evidence that House Finches can acquire trill patterns resembling those of captive canaries provides insight into vocal learning, imitation, and the flexibility of learned bird song.
Automatic Bird Sound Detection: Logistic Regression Based Acoustic Occupancy Model
| Yi-Chin Tseng, Bianca N. I. Eskelson, Kathy Martin & Valerie LeMay | Bioacoustics | 2021
Researchers integrate automated bird-call detection with occupancy modeling to estimate species occurrence while accounting for imperfect acoustic detection.
Passive Acoustic Monitoring Effectively Detects Northern Spotted Owls and Barred Owls
| Zachary J. Ruff et al. | Ornithological Applications | 2020-04-27
Autonomous recorders successfully detected Northern Spotted Owls and invasive Barred Owls across a range of forest conditions, supporting a shift toward acoustic methods for large-scale owl monitoring.
An Analysis of Avian Vocal Performance at Note and Song Levels
| David M. Logue et al. | Bioacoustics | 2020
The study examines methods for quantifying how rapidly birds can change frequency during songs and explores whether measures made at individual-note and whole-song scales reveal different aspects of vocal performance.
Autonomous Sound Recording Outperforms Human Observation for Sampling Birds
| Kevin Darras et al. | Ecological Applications | 2019
A systematic review found autonomous sound recorders can sample bird communities as effectively as or better than conventional human observation while producing permanent, standardized records that can be repeatedly analyzed.
Automated Birdsong Recognition in Complex Acoustic Environments: A Review
| Nirosha Priyadarshani et al. | Journal of Avian Biology | 2018
The review examines the technical challenges of automatically identifying birds in noisy field recordings, including overlapping calls, distant signals, environmental noise, feature extraction, and classifier design.
A Practical Comparison of Manual and Autonomous Methods for Acoustic Monitoring
| Andrew Digby et al. | Methods in Ecology and Evolution | 2013
A study of Little Spotted Kiwi compared field listening, manual review of recordings, and automated recognition, helping establish the practical advantages and limitations of autonomous acoustic wildlife surveys.
Using Songs to Identify Individual Mexican Antthrush: Comparison of Four Classification Methods
| Alexander N. G. Kirschel et al. | Bioacoustics | 2009
Researchers compared several statistical and machine-learning approaches for distinguishing individual Mexican Antthrushes from their songs, an early example of automated acoustic individual identification in wild birds.
Long-Term Stability of Song Elements in the Yellowhammer Emberiza citrinella
| P. Hansen | Bioacoustics | 1999
Long-term recordings reveal persistence in Yellowhammer song elements, illustrating how bioacoustic archives can be used to investigate cultural stability and change across years.
Bats
Linking Energy Metabolism and Echolocation: The Relationship Between Basal Metabolic Rate and Peak Frequency in Bats
| Multiple authors | Bioacoustics | 2026-02-06
A comparative analysis across bat families investigates whether the energetic demands of producing high-frequency echolocation signals are related to basal metabolic rate, linking bioacoustics with physiology and evolutionary ecology.
From Traditional to Geometric Morphometrics: A Novel Approach in Bat Bioacoustic Analysis
| Natalia Ramirez-Ortiz, M. Cristina MacSwiney G. & Sandra M. Ospina-Garcés | Bioacoustics | 2026
Researchers apply geometric morphometric techniques to the shapes of bat echolocation calls, exploring whether call shape can improve species discrimination when traditional measurements of frequency and duration overlap.
Acoustic Signal Detection of Search-Phase Echolocation Bat Calls Using a Hybrid Classification Model
A hybrid machine-learning approach is developed to recognize search-phase bat echolocation calls automatically, contributing to efforts to process large ultrasonic monitoring datasets without manual inspection.
The Bat Detector Story
| David Pye | Bioacoustics | 2025-04-21
A historical perspective traces the development of electronic bat detectors and explains how technological advances allowed researchers to convert ultrasonic echolocation into signals humans could hear, visualize, and analyze.
New Bat Detection System in India Promises More Efficient Data Collection
| Mongabay.com | Mongabay | 2025-04-11
BatEchoMon combines ultrasonic detectors, microcomputers, automated processing, solar power, and remote data transmission to make long-duration monitoring of insectivorous bats more practical in India.
Acoustic Monitoring with Miniature Drones Shows Reduced Myotis Bat Occurrence with Altitude and Drone Movement
| Lauren Dobie, David M. Bird & Kyle H. Elliott | Scientific Reports | 2025-04-10
Researchers mounted ultrasonic detectors on small drones to investigate bat activity in three dimensions and found that flight altitude and drone movement affected detections, revealing both opportunities and limitations for aerial bioacoustics.
Passive Acoustic Monitoring of Cave-Dwelling Bats with a Sonotype Classifier
| Morgane Labadie et al. | Bioacoustics | 2025
Long-term monitoring at caves in the Republic of Congo combined recordings, bat captures, and automated sonotype classification to quantify bat activity in a region where many species' acoustic repertoires remain poorly documented.
First Characterisation of Bat Echolocation Calls in Argentina
| Camila S. González Noschese et al. | Bioacoustics | 2025
Recordings from 13 bat species in northwestern Argentina provide an important regional reference library that can improve future acoustic identification and biodiversity surveys.
Importance of the Integrated Use of Bioacoustics and Mist Nets for Bat Surveys
| Jeanneson Silva de Sales et al. | Bioacoustics | 2025
Surveys in Brazil found substantial differences between bats detected with mist nets and those detected acoustically, showing that combining techniques produces a more complete picture of bat diversity.
Using Automated Passive Acoustic Monitoring to Measure Changes in Bird and Bat Vocal Activity Around Hedgerows of Different Ages
| Multiple authors | Biological Conservation | 2024
Thousands of hours of recordings from English farmland show how bird and bat acoustic activity differs around hedgerows of different ages, structures, and landscape connectivity.
Automated Bat Call Classification Using Deep Convolutional Neural Networks
| E. Schwab et al. | Bioacoustics | 2023
Deep convolutional neural networks trained on bat-call spectrograms achieved high classification performance, demonstrating how image-recognition architectures can be adapted to identify animals from sound.
Listening in the Dark: Acoustic Indices Reveal Bat Species Diversity in a Tropical Savannah
| Claysson de Aguiar Silva et al. | Bioacoustics | 2023
Hundreds of hours of recordings from Brazil's Cerrado were used to compare acoustic indices with taxonomic, phylogenetic, and functional bat diversity, showing both the potential and limitations of index-based biodiversity measurement.
Tradition vs. Innovation: Comparing Bioacoustics and Mist-Net Results to Bat Sampling
| Matheus Camargo Silva Mancini et al. | Bioacoustics | 2022
Comparing ultrasonic monitoring with mist-net captures shows that each technique detects different portions of bat communities and that combining methods can produce more complete biodiversity inventories.
Development and Test of a Bat Calls Detection and Classification Method Based on Convolutional Neural Networks
| Y. Paumen, M. Mälzer, S. Alipek, J. Moll, B. Lüdtke & H. Schauer-Weisshahn | Bioacoustics | 2022
Convolutional neural networks are used to detect and classify ultrasonic bat calls, illustrating the increasing role of deep learning in processing large acoustic datasets.
Random Forest Is the Best Species Predictor for a Community of Insectivorous Bats Inhabiting a Mountain Ecosystem of Central Mexico
| Jorge Ayala-Berdon et al. | Bioacoustics | 2021
Several classification methods are compared for identifying Mexican bats from echolocation calls, with random forests performing particularly well for the local multispecies community.
Monitoring Cave-Dwelling Bats Using Remote Passive Acoustic Detectors: A New Approach for Cave Monitoring
| Natalia Revilla-Martín et al. | Bioacoustics | 2021
Remote ultrasonic detectors placed at cave entrances can monitor bat activity repeatedly without requiring researchers to enter sensitive roosts, reducing disturbance while producing long-term information.
Variant Maps for Bat Echolocation Call Identification Algorithms
| Olga Heim et al. | Bioacoustics | 2020
The authors introduce a method for visualizing how bat-call identification algorithms respond to variations in acoustic measurements, making classifier behavior easier to understand and evaluate.
Isolation Calls from Twin Siblings Are Similar in Asian Parti-Coloured Bats
| Yu Li et al. | Bioacoustics | 2020
Vocalizations of young sibling bats show similarities that provide insight into how genetics, development, and social experience contribute to individual and family-specific acoustic signatures.
First Data on the Acoustic Characteristics of Some Chiropteran Species from Northern Algeria
| Mourad Ahmim, Ridha Dalhoumi & Dragos Stefan Mantoiu | Bioacoustics | 2020
Acoustic descriptions of bats from northern Algeria provide baseline echolocation information for a poorly documented region and improve the potential for non-invasive bat surveys in North Africa.
Spectral Call Features Provide Information About Aggression Level in Greater Mouse-Eared Bats
| Michael H. Walter & Hans-Ulrich Schnitzler | Bioacoustics | 2019
Acoustic characteristics of social calls change with aggressive context, suggesting that bat vocalizations convey information about the motivational state of the caller.
Acoustic Characterisation of Bats from Malta: Setting a Baseline for Monitoring and Conservation of Bat Populations
| Clare Marie Mifsud & Adriana Vella | Bioacoustics | 2019
Echolocation recordings establish reference characteristics for Maltese bats and provide baseline data that can support long-term monitoring of island bat populations.
Potential of Bat Pass Duration Measures for Studies of Bat Activity
| Christian Kerbiriou et al. | Bioacoustics | 2019
Researchers examine whether the duration of recorded bat passes provides useful information beyond conventional counts of acoustic events and discuss implications for estimates of bat activity.
Geographical Variation in High-Duty Cycle Echolocation of the Cryptic Common Mustached Bat Pteronotus cf. rubiginosus
| Adrià López-Baucells et al. | Bioacoustics | 2018
Echolocation calls vary geographically across populations of mustached bats, demonstrating why regional call libraries are important when identifying cryptic bat species acoustically.
Unravelling the Calls of Discrete Hunters: Acoustic Structure of Echolocation Calls of Furipterid Bats
| Fábio Falcão, Joaquín A. Ugarte-Núñez, Deborah Faria & Christini B. Caselli | Bioacoustics | 2015
Researchers characterize echolocation calls of little-known furipterid bats, adding reference information important for identifying these species during passive acoustic surveys.
Acoustic Identification of Four Species of Bats in Central Chile
| Annia Rodríguez-San Pedro & Javier A. Simonetti | Bioacoustics | 2013
Echolocation recordings from central Chile identify acoustic characteristics useful for distinguishing four bat species and demonstrate the potential for non-invasive regional bat monitoring.
The Shape of Sound: Elliptic Fourier Descriptors Discriminate Echolocation Calls of Myotis Bats
| Mathieu Lundy et al. | Bioacoustics | 2011
Researchers apply geometric shape-analysis techniques to bat-call spectrograms and show that call contour can provide information for distinguishing acoustically similar Myotis species.
Social Calls in Clear-Winged Woolly Bats Kerivoula pellucida from Malaysia
| T. Kingston, G. Jones, Z. Akbar & T. Kunz | Bioacoustics | 2000
Researchers describe social vocalizations of Malaysian woolly bats and help broaden bat bioacoustics beyond the echolocation signals most commonly studied.
Other Terrestrial Mammals
Beyond the Howl: An Acoustic Framework for Wolf Monitoring and Pack-Composition Inference
| Multiple authors | Ecologies | 2026-04-29
Recordings of free-ranging wolves in Denmark show that passive bioacoustics can help detect packs, identify individuals, and detect pups, offering a non-invasive complement to DNA surveys and other wolf-monitoring techniques.
How a Sanctuary Outside Los Angeles Has Cared for Rare Endangered Gibbons
| Associated Press | AP News | 2026
The Gibbon Conservation Center has contributed decades of research on endangered gibbons, including studies of their elaborate vocalizations, while maintaining breeding and conservation programs for several threatened species.
Forest Elephants Modulate Their Behaviour to Adapt to Sounds of Danger
| Multiple authors | Philosophical Transactions of the Royal Society B | 2025-06-12
Long-term acoustic monitoring in Central African forests shows that elephants alter patterns of activity and vocal behavior following threatening sounds such as gunfire, revealing behavioral responses that conventional surveys may miss.
Leopards' Unique "Sawing" Sounds Could Aid Conservation Efforts
| Dann Okoth | Mongabay | 2025-01-30
Researchers paired microphones with camera traps in Tanzania and found that the distinctive roaring calls of leopards contain enough individual information to potentially identify and monitor particular animals acoustically.
Detection and Classification of Captive Coppery Titi Monkey Calls
| Jen Muir et al. | Bioacoustics | 2025
Researchers developed a machine-learning model capable of detecting and classifying several Coppery Titi Monkey call types, with potential applications to animal welfare and conservation monitoring.
On Feature Representations for Marmoset Vocal Communication Analysis
| Eklavya Sarkar et al. | Bioacoustics | 2025
Self-supervised learning and other computational approaches were tested for identifying call type, caller identity, and sex in marmoset vocalizations, demonstrating how techniques developed for human speech can contribute to animal bioacoustics.
Early Detection of Human Impacts Using Acoustic Monitoring: An Example with Forest Elephants
| P. H. Wrege, F. B.-D. Bambi, P. J. F. Malonga, O. J. Samba & T. Brncic | PLOS ONE | 2024-07-26
Long-term recordings of forest elephant calls demonstrate how changes in vocal activity can reveal responses to human disturbance before population declines become obvious through conventional surveys.
Bioacoustic Classification of a Small Dataset of Mammalian Vocalisations Using Deep Learning
| Rodrigo Manriquez P, Sonja A. Kotz, Andrea Ravignani & Bart de Boer | Bioacoustics | 2024
Researchers explore deep-learning approaches designed for situations in which only limited labeled recordings are available, a common problem when studying rare or difficult-to-record mammals.
The Content of Reindeer Male Vocalisations: Acoustic Cues to Age and Size
| Laura Puch, Robert B. Weladji, Øystein Holand & Jouko Kumpula | Bioacoustics | 2024
Analysis of male reindeer calls investigates whether vocal characteristics encode information about body size and age that could be important during reproductive competition.
Evaluating Factors Affecting Species Detection Using Passive Acoustic Monitoring in Neotropical Forests
| Anja Hutschenreiter et al. | Bioacoustics | 2023
Playback experiments involving spider monkeys and other species show that recorder height, forest age, call frequency, bandwidth, and habitat structure can substantially influence the distance at which wildlife vocalizations are detected.
Toward Passive Acoustic Monitoring of Lemurs
| Multiple authors | International Journal of Primatology | 2022
Low-cost open-source acoustic recorders were tested for monitoring pale fork-marked lemurs in Madagascar, including experiments designed to estimate detection distance and investigate whether calling rates could help estimate population density.
Using Bioacoustics to Monitor Gibbons
| Multiple authors | Biodiversity and Conservation / BioAcoustica | 2021
Researchers used ordinary smartphones as low-cost acoustic recorders to detect endangered gibbon groups in Vietnam and estimate their probability of occurrence across a protected landscape.
Non-Invasive Acoustic Detection of Wolves
| Stefan M. Suter et al. | Bioacoustics | 2017
Passive recorders detected spontaneous wolf howling from free-ranging packs, demonstrating a non-invasive alternative to elicited howling surveys for monitoring an elusive and highly mobile carnivore.
Amphibians
Rediscovery of Frogs of Conservation Concern in Panama Using Passive Acoustic Monitoring and Pattern-Matching Analysis
| Brian Gratwicke et al. | Frontiers in Amphibian and Reptile Science | 2026-01-21
Automated analysis of long-term recordings helped locate rare frogs of conservation concern in Panama, illustrating how acoustic monitoring can rediscover populations that are difficult to find with conventional field surveys.
From Croaks to Species: A Review of Advances in Automated Acoustic Analysis for Anurans
| Multiple authors | Ecological Informatics | 2026
This review examines preprocessing, denoising, call segmentation, feature extraction, machine learning, deep learning, transfer learning, and few-shot learning for automatically identifying frogs and other anurans from recordings.
Monitoring Amphibians in a Changing Climate: Conservation Assessment of Natterjack Toad Using Ecoacoustics
| Multiple authors | Journal for Nature Conservation | 2026
Passive acoustic recorders were used across several breeding seasons to monitor Natterjack Toad activity in Scotland, illustrating how long-term recordings can track breeding phenology and potentially reveal responses to changing climate conditions.
Environmental Drivers of Calling Activity in a Southern Subtropical Anuran Assemblage
| Paula Pouso, Álvaro Cabana & Clara Nieto Methol | Bioacoustics | 2026
Year-round passive acoustic monitoring in Uruguay found strong seasonal patterns in frog calling and showed that temperature and photoperiod can substantially influence when reproductive vocalizations occur.
The Influence of the Chytrid Fungus on the Vocalization of Dendropsophus minutus
| Letícia Lessio, João Pedro Bovolon & Luís Felipe Toledo | Bioacoustics | 2026
Researchers investigated whether infection by the amphibian chytrid fungus alters frog vocalizations, highlighting the possibility that bioacoustic measurements could provide information about disease-related changes affecting reproduction.
State of Knowledge of Advertisement Calls in Pristimantis Frogs
| Sebastián Duarte-Marín et al. | Bioacoustics | 2026
A systematic review found that advertisement calls remain undocumented for most species in the enormous Pristimantis frog genus, creating major gaps for taxonomy, passive acoustic monitoring, automated recognition, and conservation.
Not So Silent: A Review of Sound Production in Salamanders
| Evelyn L. Beeler et al. | Bioacoustics | 2026
Contrary to their reputation as largely silent animals, at least dozens of salamander species across nearly every salamander family have documented sound production associated with behaviors including defense, reproduction, and social interactions.
Environmental Drivers of Calling Activity in the Critically Endangered Lemur Leaf Frog, Agalychnis lemur
| Fabiola Chirino et al. | Philosophical Transactions of the Royal Society B | 2025-06-12
Passive acoustic monitoring identifies environmental conditions associated with calling in the critically endangered Lemur Leaf Frog, information that can improve survey timing and conservation monitoring.
A Systematic Review of Passive Acoustic Monitoring for Anuran Conservation
| Marco Lassandro, Liam Bolitho & David Newell | Bioacoustics | 2025
A review of more than 70 studies documents rapid growth in acoustic frog monitoring while identifying geographic biases, inconsistent protocols, analytical challenges, and opportunities for standardized global monitoring.
Geographic Variation of Advertisement Calls in the Terrestrial Frog Eleutherodactylus nitidus in Southern Mexico
| Zeltzin Karina Vázquez-Hernández et al. | Bioacoustics | 2024
More than 1,600 calls from several frog populations reveal geographic differences in call structure that cannot be explained entirely by body size or temperature and may reflect evolutionary divergence.
Low Temperature Induces a Significant Decrease in Auditory Sensitivity of Xenopus laevis
| Wenxiu Li, Bicheng Zhu, Xiaomeng Zhao, Jun Li & Jianguo Cui | Bioacoustics | 2024
Auditory brainstem measurements demonstrate that cold temperatures substantially reduce hearing sensitivity in African clawed frogs, linking environmental temperature with acoustic communication and sensory ecology.
Effects of Anthropogenic Noise on Anuran Amphibians
| Valentina Zaffaroni-Caorsi et al. | Bioacoustics | 2023
A review of dozens of frog studies finds that traffic, urban development, and other human noise can alter calling, mate selection, physiology, abundance, and reproductive behavior.
Complex Acoustic Signals in Crossodactylodes, a Frog Genus Historically Regarded as Voiceless
| Marcus Thadeu T. Santos et al. | Bioacoustics | 2022
Frogs from a genus historically believed to be largely silent were found to produce structured acoustic signals, showing how basic natural-history assumptions can change when sensitive recording methods are used.
Active or Passive Acoustic Monitoring? Assessing Methods to Track Anuran Communities
| Multiple authors | Ecological Indicators | 2021
Comparisons in tropical savanna wetlands found that passive recorders could detect high frog species richness, particularly when recordings covered broader portions of the day and breeding season.
Auditory Sensitivity Changes with Diurnal Temperature Variation in Little Torrent Frogs
| Xiaoqian Sun, Longhui Zhao, Qinghua Chen, Jichao Wang & Jianguo Cui | Bioacoustics | 2020
Auditory brainstem measurements reveal that natural daily temperature changes alter hearing sensitivity at some frequencies in torrent frogs, linking environmental conditions directly to acoustic perception.
Estimating Density of Calling Male Eleutherodactylus coqui in Hawaii from Audio Recordings of Nighttime Frog Chorus
| Francis L. Benevides Jr. et al. | Bioacoustics | 2019
Researchers investigate whether the intensity and structure of nighttime frog choruses can be converted into estimates of invasive Coqui Frog population density.
A Test of the Matched Filter Hypothesis in Two Sympatric Frogs, Chiromantis doriae and Feihyla vittata
| Multiple authors | Bioacoustics | 2019
Hearing sensitivity and advertisement-call frequencies are compared in two frog species sharing the same habitat to test whether auditory systems are tuned specifically to the spectral characteristics of their own species' calls.
Atmospheric and Underwater Propagation of Bullfrog Vocalisations
| S. S. Boatright-Horowitz, C. A. Cheney & A. M. Simmons | Bioacoustics | 1999
Researchers compare how bullfrog calls propagate through air and water, providing insight into how the physical environment shapes the transmission and reception of amphibian communication signals.
Underwater Acoustic Communication in the African Pipid Frog Xenopus borealis
| D. D. Yager | Bioacoustics | 1992
The fully aquatic Xenopus borealis produces several distinct underwater call types associated with mate attraction, approach, and aggression, demonstrating a sophisticated acoustic communication system beneath the water surface.
Marine Mammals
How Decoding Beluga Whales' Chitchat May Save Them
| Phoebe Weston | The Guardian | 2026-08-27
Scientists studying beluga vocalizations are discovering complex repertoires of clicks, whistles, and other calls that maintain social relationships and transmit information, while vessel noise threatens to mask communication important to whale survival.
Summer Acoustic Occurrence of Southern Resident Killer Whales off Southern Vancouver Island
| Katherine Gavrilchuk et al. | Bioacoustics | 2026
Multi-year passive acoustic monitoring revealed important differences in the summer occurrence of endangered Southern Resident killer whales across monitoring sites near Vancouver Island and identified areas of particularly frequent acoustic presence.
Exploring YOLOv8 for Automatic Detection of Dolphin Whistles in Spectrograms
| Vicent Avaria-Avaria et al. | Bioacoustics | 2026
Researchers adapted the YOLOv8 computer-vision system to recognize dolphin whistles displayed as spectrograms, demonstrating another way image-recognition technologies can automate processing of large marine acoustic datasets.
Listening to Whales Is Key to Their Conservation
| Mike DiGirolamo | Mongabay | 2025-04-29
Researchers discuss how whale songs can provide information about feeding conditions and ecosystem change while emphasizing that acoustic activity must be interpreted carefully when estimating whale abundance.
Counting Whales by Eavesdropping on Their Chatter, with Help from Machine Learning
| Abhishyant Kidangoor | Mongabay | 2025-03-18
Researchers combined underwater recordings, machine learning, and aerial surveys to estimate numbers of North Atlantic right whales, advancing efforts to move acoustic monitoring from simple presence detection toward population estimation.
Whale Songs Rise and Fall with Food Supply
| Bobby Bascomb | Mongabay | 2025-03-12
Long-term hydrophone recordings indicate that singing activity in humpback, blue, and fin whales can change alongside prey availability, showing that whale acoustics may reveal ecological conditions as well as whale presence.
Acoustic Characteristics and Context of Buzzes and Rasps Produced by Northern Bottlenose Whales
| Caroline E. Haas et al. | Bioacoustics / University of St Andrews | 2025-02-18
Tag recordings from deep-diving Northern Bottlenose Whales distinguish rapid click sequences associated with different behavioral contexts and expand knowledge of the acoustic repertoire of this poorly observed cetacean.
Listening for Whales: Using Passive Acoustic Monitoring to Track North Atlantic Right Whales
| NOAA Fisheries | NOAA Fisheries | 2024-11-20
NOAA describes how underwater acoustic systems are moving toward near-real-time detection of endangered North Atlantic right whales, information that can help warn mariners and reduce vessel-strike risks.
Dolphin Self-Talk: Unusual Acoustic Behavior of a Solitary Bottlenose Dolphin
Researchers document unusual vocal production by a solitary bottlenose dolphin, providing insight into the functions of dolphin calls when normal social partners are absent.
Extracting Dolphin Whistles in Complex Acoustic Scenarios: A Case Study in the Bay of Biscay
| Ramón Miralles, Carles Gallardo, Guillermo Lara & Manuel Bou Cabo | Bioacoustics | 2024
A signal-processing method improves extraction of dolphin whistle contours from recordings containing overlapping vocalizations and variable noise, addressing an important bottleneck in automated cetacean analysis.
Sperm Whale Coda Patterns in the Gulf of Catania, South-Western Ionian Sea, Italy
| Davide M. Lelong et al. | Bioacoustics | 2024
Analysis of Mediterranean sperm whale codas reveals several recurring click patterns and contributes to research showing that culturally transmitted coda repertoires can differ among whale populations.
Evidence of Signature Whistles Produced by Indian Ocean Bottlenose Dolphins in Mozambique
| Rachel Probert, Angie Gullan, Diana Rocha, Sasha Dines & Tess Gridley | Bioacoustics | 2023
Twelve years of recordings provide evidence that Indian Ocean bottlenose dolphins produce individually distinctive, stable whistle types and suggest that acoustic identity signaling may differ among dolphin populations.
Passive Acoustic Monitoring of Sperm Whales and Anthropogenic Noise in the Mediterranean Sea
| Marion Poupard et al. | Scientific Reports | 2022-02-07
Multi-year underwater recordings from the Pelagos Sanctuary were used to study both sperm whale acoustic activity and human-generated noise, demonstrating the value of long-term marine listening stations.
Acoustic Identification of Sympatric Indo-Pacific Finless Porpoise and Indo-Pacific Humpback Dolphin
| Satoko S. Kimura, Tomoka Sagara, Ken Yoda & Louisa S. Ponnampalam | Bioacoustics | 2022
Researchers identify acoustic characteristics that can distinguish two cetaceans occupying the same waters, improving the usefulness of passive acoustic surveys where visual species identification is impossible.
Characterization and Classification Method of Burst Pulses Produced by Guiana Dolphins
Guiana dolphin burst-pulse sounds are analyzed and classified to better understand a vocalization type that may play important roles in social behavior and communication.
I Beg Your Pardon? Acoustic Behaviour of a Wild Solitary Common Dolphin Who Interacts with Harbour Porpoises
| Mel Cosentino et al. | Bioacoustics | 2022
Recordings of a solitary common dolphin interacting with harbor porpoises provide an unusual opportunity to investigate whether cetaceans modify their acoustic behavior during interspecies encounters.
Intraspecific Variation in Short-Beaked Common Dolphin's Whistle Repertoire
| Bruna Pagliani, Thiago O. S. Amorim, Franciele R. De Castro & Artur Andriolo | Bioacoustics | 2022
More than 1,600 whistles reveal geographic and temporal variation in common dolphin vocalizations, illustrating how whistle characteristics can differ within a single species.
Are Dolphins Modulating Whistles in Interspecific Group Contexts?
| Yasmin Viana et al. | Bioacoustics | 2022
Bottlenose dolphins produced acoustically different whistles when associating with other dolphin species, suggesting that social context and mixed-species interactions can influence vocal behavior.
Humpback Whale Social Call Production Reflects Both Motivational State and Arousal
| Dana A. Cusano, Katherine L. Indeck, Michael J. Noad & Rebecca A. Dunlop | Bioacoustics | 2022
Humpback whale groups altered call rates, call bouts, and repertoire diversity when social conditions changed, suggesting that non-song vocalizations carry information about motivation and arousal.
Hidden Markov Model for Detection of Mysticetes' Vocalisations Based on Principal Component Analysis
Researchers combine principal component analysis with hidden Markov models to automate detection of humpback and Bryde's whale vocalizations in large passive-acoustic datasets.
An Automated Passive Acoustic Monitoring System for Real-Time Sperm Whale Threat Prevention
| M. Sanguineti et al. | Applied Acoustics | 2021
An automated monitoring system was developed for detecting endangered Mediterranean sperm whales in near real time, illustrating how acoustic detection could contribute to reducing collisions and other human threats.
Optimizing Passive Acoustic Systems for North Atlantic Right Whale Detection and Localization
| Cédric Gervaise et al. | Applied Acoustics | 2021
Researchers modeled how passive acoustic networks should be designed to detect and locate North Atlantic right whale calls in the noisy Gulf of St. Lawrence, where shipping can complicate whale monitoring.
First Description of Whistles of Black Sea Short-Beaked Common Dolphins
| Elena Panova, Alexandr Agafonov & Irina Logominova | Bioacoustics | 2021
Analysis of more than 1,000 whistles provides the first detailed acoustic description of the endemic Black Sea form of the short-beaked common dolphin and identifies characteristics useful for passive monitoring.
Use of Recurrence Plots for Identification and Extraction of Patterns in Humpback Whale Song Recordings
| F. Malige, D. Djokic, J. Patris, R. Sousa-Lima & H. Glotin | Bioacoustics | 2021
Recurrence plots provide a mathematical way to visualize repeated patterns and hierarchical structures in continuous humpback whale songs while reducing reliance on subjective human classification.
Vocalizations of Common Minke Whales in an Eastern North Pacific Feeding Ground
| Katrina Nikolich & Jared R. Towers | Bioacoustics | 2020
Researchers document previously undescribed calls from North Pacific minke whales on a summer feeding ground and explore ecological explanations for why the animals vocalize relatively infrequently there.
Crowd Intelligence Can Discern Between Repertoires of Killer Whale Ecotypes
| Anastasya Yu. Danishevskaya et al. | Bioacoustics | 2020
Multiple independent human observers classified killer whale calls, and combining their judgments improved recognition of differences among some populations and ecotypes compared with relying on individual observers.
Presence and Behavior of Harbor Porpoises Around Set Nets Revealed Using Passive Acoustic Monitoring
| Multiple authors | Fisheries Research | 2018
Acoustic loggers recorded harbor porpoise movements around fishing nets and revealed that animals sometimes enter and leave nets without becoming bycatch, providing new information relevant to fisheries management.
Handling Dolphin Detections from C-PODs: Development of Acoustic Parameters for Verification and Identification
| James R. Robbins et al. | Bioacoustics | 2016
Researchers evaluate click-detection data from static acoustic loggers and develop criteria that improve discrimination of genuine dolphin activity from false detections and other underwater sounds.
Detection Rates of Wild Harbour Porpoises and Bottlenose Dolphins Using Static Acoustic Click Loggers Vary with Depth
| Marta Sostres Alonso & Hanna K. Nuuttila | Bioacoustics | 2015
Acoustic detectors positioned at different depths recorded substantially different rates of cetacean clicks, showing how instrument placement can bias estimates of marine mammal occurrence.
Fish, Reefs & Aquatic Ecosystems
Coral Restoration Alters Reef Soundscapes but Machine Learning and Manual Analyses Suggest Different Recovery Rates
| Emily Maria Croasdale et al. | PLOS ONE | 2026-05-27
Researchers examining restored coral reefs found measurable changes in underwater soundscapes, but manual and machine-learning analyses produced different impressions of recovery, highlighting the importance of analytical methodology.
Decoding Coral Reef Soundscapes for Monitoring and Conservation
| Multiple authors | Trends in Ecology & Evolution | 2026
Coral reefs produce complex soundscapes created by fish, invertebrates, environmental processes, and human activity. Researchers argue that passive acoustic monitoring can provide valuable information about reef condition when soundscape patterns are interpreted carefully alongside ecological processes.
Optimal Feature Selection and Model Explanation for Reef Fish Sound Classification
Machine-learning techniques are used to determine which acoustic characteristics are most useful for distinguishing reef-fish sounds, while explainable-AI methods reveal why the classifier makes particular decisions.
Soundscape and Fish Passive Acoustic Monitoring Around a North Sea Gas-Production Platform in the Dogger Bank
| M. Bolgan, S. J. Bhalla, I. B. Todd & V. L. G. Todd | PLOS ONE | 2025-04-02
Hydrophones around an offshore gas platform recorded fish sounds and broader underwater soundscapes, demonstrating how passive acoustics can investigate marine communities around industrial infrastructure.
Passive Acoustic Monitoring of Fish Choruses: A Review to Inform the Development of a Monitoring and Management Tool
| Lauren Amy Hawkins et al. | Reviews in Fish Biology and Fisheries | 2025-03-19
This review examines fish choruses as indicators of spawning, habitat use, biodiversity, and ecosystem condition and discusses how standardized acoustic monitoring could contribute to fisheries management.
The Biological Soundscape of Temperate Reefs in the Wadden Sea
| Maryann S. Watson et al. | Scientific Reports | 2025-03-17
Underwater recordings document a rich temperate-reef soundscape generated by fish, invertebrates, environmental processes, and human activity, providing a baseline for ecological monitoring in the Wadden Sea.
Underwater Soundscape Analysis Reveals Fish Assemblage Contrasts Between Protected and Exploited Areas in an African Mangrove Delta
| Multiple authors | Biological Conservation | 2025
Acoustic recordings from an African mangrove ecosystem reveal differences between protected and harvested areas, showing how underwater soundscapes may provide non-invasive indicators of fish-community condition.
Soundscape Analysis Reveals Fine Ecological Differences Among Coral Reef Habitats
| Multiple authors | Ecological Indicators | 2025
Researchers demonstrate that reef soundscapes contain acoustic differences among habitat types that may be difficult to detect through broad ecological surveys, supporting soundscape monitoring as a tool for reef assessment.
Insects & Other Invertebrates
Bioacoustic Monitoring and AI Applications in Insect Pest Management
| Ivana Majić et al. | Applied Sciences | 2026-05-22
Bioacoustic sensors combined with artificial intelligence could provide continuous monitoring of insect pests by detecting sounds associated with feeding, movement, flight, and communication, potentially reducing dependence on labor-intensive surveys and chemical pesticides.
A Review of Acoustic Systems for Insect Monitoring: From Recording Technologies to Species Recognition Performance
| Multiple authors | Ecological Informatics | 2026
Acoustic monitoring can detect insect communication, feeding, movement, wing beats, and other sounds useful for biodiversity surveys and pest management. The review evaluates recording systems, automated identification methods, performance limitations, and the need for standardized monitoring procedures.
Acoustic Monitoring for Tropical Insect Conservation
| Klaus Riede & Rohini Balakrishnan | Philosophical Transactions of the Royal Society B | 2025-06-12
Tropical insects produce an enormous diversity of sounds, and the authors argue that passive acoustic monitoring could help fill major gaps in insect biodiversity information as automated classifiers and low-cost recorders improve.
Temporal Patterns of Amazonian Insect Acoustic Activity
| Nia Howells et al. | Philosophical Transactions of the Royal Society B | 2025-06-12
Long-term recordings reveal strong daily and seasonal patterns in insect acoustic activity in Amazonian forests, providing a foundation for using insect sound as an ecological monitoring signal.
Recent Technological Developments Allow Passive Acoustic Monitoring of Grasshoppers and Crickets
| Multiple authors | Basic and Applied Ecology | 2025
Cheaper autonomous recorders and improved automated classifiers are making landscape-scale monitoring increasingly feasible for Orthoptera, a group traditionally surveyed through labor-intensive expert fieldwork.
How Well Do Acoustic Recordings Characterize Properties of Bee Floral Sonication Vibrations?
| Paul A. De Luca et al. | Bioacoustics | 2020
Researchers compare airborne recordings with direct vibration measurements to determine how accurately microphones represent the buzzing vibrations bees generate when extracting pollen from flowers.
Predicting Species Identity of Bumblebees Through Analysis of Flight Buzzing Sounds
| Anton Gradisek et al. | Bioacoustics | 2017
Measurements of the characteristic buzzing produced during bumblebee flight are used to determine whether species can be distinguished acoustically, suggesting possibilities for automated pollinator monitoring.
An Automatic Acoustic Response System for Behavioural Studies of Duetting Insects
| T. J. Hammond, W. J. Bailey & G. R. Hammond | Bioacoustics | 2003
An interactive playback system automatically detects male insect calls and produces precisely timed simulated female responses, allowing controlled experiments on the timing and structure of acoustic duets.
A Simple Method for Recording Low-Amplitude Sounds: Application to Courtship Song of Drosophila melanogaster
| T. Aubin, F. Rybak & B. Moulin | Bioacoustics | 2000
A recording technique designed for very quiet animal sounds enables detailed analysis of fruit-fly courtship songs and illustrates specialized methods required for miniature acoustic signalers.
Species-Specific Sounds in Water Bugs of the Genus Micronecta. Part I: Sound Analysis
| I. M. King | Bioacoustics | 1999
Water bugs produce distinctive underwater sounds whose temporal and spectral characteristics can help distinguish species, demonstrating the diversity of acoustic communication among aquatic insects.
