Acoustic monitoring for conservation in tropical forests: examples from forest elephants
Abstract
Summary: The accelerating loss of biodiversity worldwide demands effective tools for monitoring animal populations and informing conservation action. In habitats where direct observation is difficult (rain forests, oceans), or for cryptic species (shy, nocturnal), passive acoustic monitoring (PAM) provides cost‐effective, unbiased data collection.PAM has broad applicability in terrestrial environments, particularly tropical rain forests. Using examples from studies of forest elephants in Central African rain forest, we show how PAM can be used to investigate cryptic behaviour, mechanisms of communication, estimate population size, quantify threats, and assess the efficacy of conservation strategies. We discuss the methodologies, requirements, and challenges of obtaining these data using acoustics. Where applicable, we compare these methods to more traditional approaches. While PAM methods and associated analysis are maturing rapidly, mechanisms are needed for processing the dense raw data efficiently with standard computer hardware, speeding development of detection algorithms, and harnessing communication networks to move data from the field to research facilities. Passive acoustic monitoring is a viable and cost‐effective tool for conservation and should be incorporated in monitoring schemes much more broadly. The capability to quickly assess changes in behaviour, population size, and landscape use, simultaneously over large geographical areas, makes this approach attractive for detecting human‐induced impacts and for assessing the success of conservation strategies.
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These cloud-linked systems are already being used to track forest elephants, detect poaching, and monitor rare species on scales once thought impossible.
“These systems are already being used to track forest elephants, detect poaching, and monitor rare species on scales once thought impossible”
From Listening forward: emerging roles of bioacoustics in ecology, evolution, and conservation (2026) · cites this paper as Wrege et al. 2017
By streaming sound and processing it locally with edge AI, real-time monitoring systems alert rangers to gunshots, chainsaws, or endangered species calls within minutes, enabling rapid intervention.
“By streaming sound and processing it locally with edge AI, these systems alert rangers to gunshots, chainsaws, or endangered species calls within minutes, enabling rapid intervention (Aide et al. 2013; Wrege et al. 2017).”
From Listening forward: emerging roles of bioacoustics in ecology, evolution, and conservation (2026) · cites this paper as Wrege et al. 2017
Real-time monitoring networks are no longer just experimental; they are beginning to reshape conservation practice.
“Real-time monitoring networks (see Sect. 3.1) are no longer just experimental—they are beginning to reshape conservation practice.”
From Listening forward: emerging roles of bioacoustics in ecology, evolution, and conservation (2026) · cites this paper as Wrege et al. 2017
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“These systems are already being used to track forest elephants, detect poaching, and monitor rare species on scales once thought impossible (Wrege et al. 2017).”
- Authors
- Wrege, P. H., Rowland, E. D., Keen, S., & Shiu, Y.
- Affiliations
- Cornell Lab of Ornithology (US)
- Corresponding author
- Wrege, Peter H.
- Venue
- Methods in Ecology and Evolution
- Publisher
- Wiley
- Published
- 2017-02-09
- Volume
- 8
- Issue
- 10
- Pages
- 1292-1301
- ISSN
- 2041-210X (ISSN-L)
- OpenAlex
- W2567936177
- Cited by
- 191
- References
- 48
- Citations by year
- 2026: 20 · 2025: 33 · 2024: 9 · 2023: 21 · 2022: 27 · 2021: 34 · 2020: 17 · 2019: 15 · 2018: 10 · 2017: 5
- FWCI
- 9.70
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Methods in Ecology and Evolution (publishedVersion)
- Funders
- U.S. Fish and Wildlife Service
- International Fund for Animal Welfare
- Topics
- Physical Sciences › Environmental Science › Ecology › Wildlife Ecology and Conservation
- Physical Sciences › Environmental Science › Ecology › Marine animal studies overview
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Developmental Biology › Animal Vocal Communication and Behavior
- Keywords
- passive acoustic monitoring, forest elephants, cryptic species, animal communication, population size estimation, conservation monitoring, tropical rainforest, detection algorithm
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