A roadmap for survey designs in terrestrial acoustic monitoring

Remote Sensing in Ecology and Conservation, Journal Year: 2019, Volume and Issue: 6(3), P. 220 - 235

Published: Nov. 13, 2019

Abstract Passive acoustic monitoring ( PAM ) is increasingly popular in ecological research and conservation programs, with high‐volume long‐term data collection provided by automatized sensors offering unprecedented opportunities for faunal ecosystem surveys. Practitioners newcomers interested can easily find technical specifications microphones, but guidelines on how to plan survey designs are largely scattered over the literature. Here, we (i) review spatial temporal sampling used passive monitoring, (ii) provide a synthesis of crucial aspects design (iii) propose workflow optimize recording autonomy schedules. From 1992 2018, most 460 studies applying terrestrial environments have single recorder per site, covered broad scales rotated recorders between sites effort. Continuous specific diel periods was main procedure used. When schedules were applied, larger number recordings hour generally associated smaller length. For design, proposed estimate memory/battery costs, assess signal detectability order recover maximum biological information evaluate cost‐benefit scenarios effort budget address potential biases from given design. Establishing standards will improve quality inferences scope promote essential standardization cross‐scale understand biodiversity trends changing world.

Language: Английский

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Comparative bioacoustics: a roadmap for quantifying and comparing animal sounds across diverse taxa

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2021, Volume and Issue: 96(4), P. 1135 - 1159

Published: March 2, 2021

Animals produce a wide array of sounds with highly variable acoustic structures. It is possible to understand the causes and consequences this variation across taxa phylogenetic comparative analyses. Acoustic evolutionary analyses are rapidly increasing in sophistication such that choosing appropriate approaches increasingly difficult. However, correct choice analysis can have profound effects on output inferences. Here, we identify address some challenges for growing field by providing roadmap quantifying comparing sound context researchers broad range scientific backgrounds. Sound, as continuous, multidimensional trait be particularly challenging measure because it hard variables compared also no small feat process analyse resulting high-dimensional data using subsequent analysis. Additionally, terminological inconsistencies role learning development traits need considered. Phylogenetic their own sets caveats consider. We provide set recommendations delimiting signals into discrete, comparable units. present three-stage workflow extracting relevant data, including options multivariate dimensionality reduction compatible then summarize available how they been used bioacoustics, limitations behavioural data. Lastly, recommend apply these methods study systems. In way, an integrated framework aid quantitative cross-taxa animal addition, advocate standardization terminology disciplines taxa, adoption automated feature extraction, establishment strong archival practices recordings Combining our proposed will greatly advance reproducibility, biological interpretation, longevity bioacoustic studies.

Language: Английский

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THE STUDY OF BIRD VOCALIZATIONS IN NEOTROPICAL HABITATS: CURRENT KNOWLEDGE AND FUTURE STEPS

Ornitología Neotropical, Journal Year: 2025, Volume and Issue: 35(2)

Published: Jan. 18, 2025

Research on avian bioacoustics in the Neotropics has surged over last several decades due to increased interest large diversity of vocal behaviors and vocalization broader accessibility recording equipment software. Here, we present a synthesis current past knowledge Neotropical bird bioacoustics. This is result symposium "Bioacoustics Neotropics", organized for XI Ornithological Congress San Jose, Costa Rica, July 2019. We covered what consider main topics that have been studied this region 30 years. Our review includes repertoire descriptions, geographic variation, behaviors, seasonality, duetting, genetic association, playback experiments. Additionally, information believe may be veins investigation coming future Neotropics, considering species are found new investigations developed other areas. expect work as summary literature guide stimulate research important areas within field Neotropics.

Language: Английский

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MAARU: Multichannel Acoustic Autonomous Recording Unit for spatial ecosystem monitoring.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 26, 2024

Acoustic localisation, which relies on simultaneous multi-microphone recording, adds spatial information to recorded audio and has been used in ecosystem monitoring count individuals improve abundance estimates, locate illegal activities such as logging/poaching, monitor behaviour habitat use or species interactions. Studies have shown many advantages of acoustic but uptake remains limited the equipment is often expensive, inaccessible, only suitable for short-term deployments. Here, we present a low-cost, open-source, 6-channel recorder built entirely from commercially available components can be integrated into solar-powered, networked system. The MAARU (Multichannel Autonomous Recording Unit) works long-term autonomous, passive, ad-hoc We introduce MAARU's hardware software results lab field tests investigating device's durability, localisation accuracy, other applications. provides multichannel data with similar costs power demands equivalent omnidirectional recorders. devices deployed UK Brazil, where MAARUs accurately localise pure tones up 6kHz 65dB bird calls far 8m away (±10° range, 100% >60% signals respectively), louder may even further detection radii. also show how beamforming ID confidence scores by 20%+ recall 10%+ when using BirdNET automated identification algorithms. an accessible, low-cost option those looking explore soundscape ecology easily. Ultimately, added directional element recording provided allows new type exploration sonic environments.

Language: Английский

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Global analysis of acoustic frequency characteristics in birds

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2034)

Published: Nov. 1, 2024

Animal communication plays a crucial role in biology, yet the wide variability vocalizations is not fully understood. Previous studies birds have been limited taxonomic and analytical breadth. Here, we analyse an extensive dataset of >140 000 recordings from 8450 bird species, representing nearly every avian order family, under structural causal model framework, to explore influence eco-evolutionary traits on acoustic frequency characteristics. We find that body mass, beak size, habitat associations geography characteristics, with varying degrees interaction song acquisition type. no evidence for vegetation density, sexual dimorphism, range size competition our measures Our results, built decades researchers’ empirical observations collected across globe, provide new breadth about how processes shape communication.

Language: Английский

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Geographically well-distributed citizen science data reveals range-wide variation in the chipping sparrow's simple song

Animal Behaviour, Journal Year: 2020, Volume and Issue: 161, P. 63 - 76

Published: Feb. 9, 2020

Geographical variation has been widely studied in oscine songbirds, with particular attention paid to the interplay between variables associated learned song and dispersal. While most field-based studies have focused on discrete dialects, analysing data from quickly growing citizen science libraries could uncover geographical patterns species previously thought exhibit random song. Specifically, using birdsong databases, we test whether chipping sparrow, Spizella passerina, is geographically structured a continental scale. The sparrow particularly well-suited for this study, since individuals simple of one repeated syllable, only beginning their first breeding season adjust before crystallization shown match nearby neighbour while establishing territory. If sparrows adopt neighbour-matching strategy, might expect local syllable similarity; contrast, field that diversity maintained over time. We analyse 820 individual recordings simple, yet diverse, assess long-range formed despite variation. found significant correlations features distance, longitude but not latitude: eastern United States Canada sing at slower rate (fewer, longer syllables) than western population. However, comparing types regions, diverse persist across species' range. To better contextualize our findings, re-evaluate available genetic sequences differentiation populations which differences. Our results suggest there are two culturally distinct subpopulations migratory genetically indistinguishable mitochondrial DNA, motivating future migration additional sequencing nuclear DNA.

Language: Английский

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Ecological adaptation and birdsong: how body and bill sizes affect passerine sound frequencies

Behavioral Ecology, Journal Year: 2022, Volume and Issue: 33(4), P. 798 - 806

Published: April 21, 2022

Abstract The avian bill is finely adjusted to foraging ecology and, as part of the vocal tract, it may also affect sexual signals such songs. Acoustic theory predicts that larger bills lower resonant frequency tracts, allowing larger-billed species emphasize sound frequencies. Theory identical changes in gape allow singing over a wider bandwidth species. We tested these associations between size and frequencies song, controlling for body mass, across ca. 1000 taxonomically-diverse passerines. Phylogenetically informed analyses indicated both sizes are negatively related songs, with additive effects similar strength. Analyses reduced datasets, decrease bill-body associations, effect remains thus not an artefact its covariation size. Sound was only but size, perhaps because large greater modulation hinder fast movement. Since has major role explaining differences birdsong frequency, can be magic trait promotes reproductive isolation consequence ecological divergence.

Language: Английский

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Body size shapes song in honeyeaters

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2021)

Published: April 24, 2024

Birdsongs are among the most distinctive animal signals. Their evolution is thought to be shaped simultaneously by habitat structure and constraints of morphology. Habitat affects song transmission detectability, thus influencing (the acoustic adaptation hypothesis), while body size beak shape necessarily constrain characteristics morphological constraint hypothesis). Yet, support for hypotheses remains equivocal, their simultaneous examination infrequent. Using a phenotypically diverse Australasian bird clade, honeyeaters (Aves: Meliphagidae), we compile dataset consisting song, environmental, variables 163 species jointly examine predictions these two hypotheses. Overall, find that constrains frequency pace in honeyeaters. Although type environmental temperature influence aspects indirect, likely via effects variation on size, with some evidence elevation peak frequency. Our results demonstrate morphology has an overwhelming birdsong, hypothesis, environment playing secondary role generally rather than structure. These suggest changing (a consequence both global such as climate change local transformation) will substantially nature birdsong.

Language: Английский

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How index selection, compression, and recording schedule impact the description of ecological soundscapes

Ecology and Evolution, Journal Year: 2021, Volume and Issue: 11(19), P. 13206 - 13217

Published: Aug. 26, 2021

Acoustic indices derived from environmental soundscape recordings are being used to monitor ecosystem health and vocal animal biodiversity. Soundscape data can quickly become very expensive difficult manage, so compression or temporal down-sampling sometimes employed reduce storage transmission costs. These parameters vary widely between experiments, with the consequences of this variation remaining mostly unknown.We analyse field North-Eastern Borneo across a gradient historical land use. We quantify impact experimental (MP3 compression, recording length subsetting) on descriptors (Analytical Indices convolutional neural net AudioSet Fingerprint). Both descriptor types were tested for their robustness parameter alteration usability in classification task.We find that both drive considerable calculated index values. However, we effects subsetting performance models is minor: much more strongly determined by acoustic choice, Audioset fingerprinting offering substantially greater (12%-16%) levels classifier accuracy, precision recall.We advise using Fingerprint analysis, finding superior consistent even small pools data. If bottleneck study, recommend Variable Bit Rate encoded (quality = 0) file size 23% without affecting most Analytical Index The be compressed further Constant encoding 64 kb/s (8% size) any detectable effect. recommendations allow efficient use restricted whilst permitting comparability results different studies.

Language: Английский

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Continent‐wide patterns of song variation predicted by classical rules of biogeography

Ecology Letters, Journal Year: 2022, Volume and Issue: 25(11), P. 2448 - 2462

Published: Sept. 20, 2022

Physiological constraints related to atmospheric temperature pose a limit body and appendage size in endothermic animals. This relationship has been summarised by two classical principles of biogeography: Bergmann's Allen's rules. Body may also constrain other phenotypic traits important ecology, evolution behaviour, such effects have seldom investigated at continental scale. Through multilevel-modelling approach, we demonstrate that continent-wide morphology African barbets follows predictions rule, mirrors variation song pitch, an acoustic trait species recognition sexual selection. Specifically, on frequency accordance with rule dwarf those adaptation Our findings suggest macroecological patterns can influence ecology evolution, provide baseline for further studies the environmental change bird song.

Language: Английский

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