DeepForestSound: a multi-species automatic detector for passive acoustic monitoring in African tropical forests, a case study in Kibale National Park
Authors: Gabriel Dubus, Théau d'Audiffret, Claire Auger, Raphaël Cornette, Sylvain Haupert, Innocent Kasekendi, Raymond Katumba, Hugo Magaldi, Lise Pernel, Harold Rugonge, Jérôme Sueur, John Justice Tibesigwa, Sabrina Krief
Organizations: Eco-Anthropologie, Muséum National d’Histoire Naturelle, UMR7206, Paris, France · Sebitoli Chimpanzee Project, Great Ape Conservation Project, Sebitoli, Kibale National Park, Fort Portal, Uganda · N’lab, Nitidae Association, Montpellier, France · Institut de Systématique, Evolution, Biodiversité (ISYEB), UMR7205 Centre National de la Recherche Scientifique, MNHN, SU, EPHE-PSL, UA, Paris, France · Centre d’Ecologie et des Sciences de la Conservation (CESCO), UMR CNRS Sorbonne Université 7204, Muséum national d’Histoire naturelle, Paris, France · Uganda Wildlife Authority, Kampala, Uganda
Passive Acoustic Monitoring (PAM) is widely used for biodiversity assessment. Its application in African tropical forests is limited by scarce annotated data, reducing the performance of general-purpose ecoacoustic models on underrepresented taxa. In this study, we introduce DeepForestSound (DFS), a multi-species automatic detection model designed for PAM in African tropical forests. DFS relies on a semi-supervised pipeline combining clustering of unannotated recordings with manual validation, followed by supervised fine-tuning of an Audio Spectrogram Transformer (AST) using low-rank adaptation, which is compared to a frozen-backbone linear baseline (DFS-Linear). The framework supports the detection of multiple taxonomic groups, including birds, primates, and elephants, from long-term acoustic recordings. DFS was trained on acoustic data collected in the Sebitoli area, in Kibale National Park, Uganda, and evaluated on an independent dataset recorded two years later at different locations within the same forest. This evaluation therefore assesses generalization across time and recording sites within a single tropical forest ecosystem. Across 8 out of 12 taxons, DFS outperforms existing automatic detection tools, particularly for non-avian taxa, achieving average AP values of 0.964 for primates and 0.961 for elephants. Results further show that LoRA-based fine-tuning substantially outperforms linear probing across taxa. Overall, these results demonstrate that task-oriented, region-specific training substantially improves detection performance in acoustically complex tropical environments, and highlight the potential of DFS as a practical tool for biodiversity monitoring and conservation in African rainforests.
TABLE I: Number of annotated vocalizations used for training and number of positive files used for evaluation, per taxon. Sebitoli 2023 refers to passive acoustic recordings collected in 2023 in the Sebitoli area. RHD denotes recordings collected with handheld devices during direct field observations. CT refers to audio segments extracted from camera trap videos. PAD denotes publicly available datasets. Sebitoli 2025 (eval) reports the number of positive one-minute audio files used for evaluation.
Passive acoustic monitoring (PAM) enables large-scale biodiversity assessment, but continuous recording generates large amounts of non-informative audio, creating challenges for storage, power consumption, and long-term edge deployment. Bird audio detection (BAD), which identifies bird vocalizations, can reduce this burden by filtering irrelevant recordings before downstream analysis. However, most BAD systems are trained on temperate datasets despite tropical soundscapes being denser, more species-rich, and acoustically unpredictable. To address this gap, we introduce SEABAD (Southeast Asian Bird Activity Detection), a dataset of 50,000 curated three-second clips from Southeast Asian soundscapes, evenly balanced between bird-present and bird-absent samples. The dataset spans 1,677 bird species and is standardized to 16 kHz mono audio for embedded and low-power inference. We developed a dual-branch curation pipeline: a six-stage positive-label workflow applied to Xeno-Canto recordings, alongside six source-specific negative-label extractions from environmental datasets. These procedures reduced class imbalance by 13.7% (Gini coefficient: 0.601 to 0.519). A manual audit of 1,000 positive clips confirmed 97.8% +/- 0.9% labeling accuracy. Baseline experiments using MobileNetV3-Small achieved 99.57% +/- 0.25% accuracy and 0.9985 +/- 0.0002 AUC across three random seeds. SEABAD and the full curation pipeline are publicly released to support tropical BAD research and energy-efficient acoustic monitoring.
Muhammad Mun'im Ahmad Zabidi, Mohd Yamani Idna Idris, Norisma Idris
Faculty of Computer Science and Information Technology, Universiti Malaya, Kuala Lumpur, Malaysia
Passive acoustic monitoring enables continuous, non-invasive biodiversity assessment across diverse ecosystems. The scale of these datasets has driven the adoption of machine learning, with supervised approaches showing strong performance. However, supervised methods require time-resolved annotated datasets, which remain scarce, especially in complex tropical soundscapes. We present PteroSet, a curated dataset of strongly annotated Neotropical bird vocalizations recorded in Puerto Asis (Putumayo) and Pivijay (Magdalena), Colombia, between 2023 and 2025. The dataset comprises 563 recordings (73.62 h) and 15,372 time-frequency annotations, including 6,702 events identified to the species level across 168 species. We release the annotations in a COCO-inspired JSON schema that unifies audio files, taxonomic categories, and labels for machine learning workflows. Beyond providing annotated data, PteroSet serves as a realistic benchmark that highlights key characteristics of tropical soundscapes, including acoustic co-occurrence and domain shift across recording sites. We provide a deep learning baseline for binary bird detection, demonstrating PteroSet's usability and the challenges it presents.
Daniela Ruiz, Juan Sebastián Ulloa, Zhongqi Miao +11
Microsoft AI for Good Research Lab, Redmond, Washington, United States · Universidad de Los Andes, Bogotá, Colombia, Center for Research and Formation in Artificial Intelligence · Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, Bogotá, Colombia +2
Camera-trap monitoring in African tropical forests increasingly extends beyond closed-canopy interiors to riverbanks, clearings, and park edges. Among available open tools for African forest camera-trap classification, DeepForestVision is the only one providing a matched offline workflow for both photographs and videos, and previous work showed that it outperformed other available baselines on a comparable benchmark. However, it was designed for closed-canopy, ground-level forest interiors and uses a 35-class prediction space that becomes too coarse when deployments encounter arboreal primates, birds, semi-aquatic taxa, or human-associated confounders such as livestock. We present DeepForestVisionV2, an ecology-driven expansion from 35 to 64 prediction classes (61 animal classes plus human, vehicle, and blank) designed to address three recurrent deployment gradients: vertical stratification, scene openness, and anthropogenic interfaces. DeepForestVisionV2 retains the same offline workflow and is trained on 1,535,010 photographs and 243,354 videos from multi-country African tropical-forest projects. Evaluation combines a cross-country cropped-photo validation set, used to assess robustness across sites and camera-trap settings, with three held-out Uganda video benchmarks spanning the targeted gradients. On the validation set, DeepForestVisionV2 reaches 0.86 accuracy, 0.82 macro-F1, and 0.81 balanced accuracy. On the deployment benchmarks, it preserves or improves baseline accuracy despite its harder classification task, while increasing the number of identified taxa from 22 to 29 in forest-interior videos and from 4 to 9 at riverbanks. In the park-edge use case, it raises accuracy from 0.62 to 0.86 and reduces false alarms from 11 to 0. These results show that DeepForestVisionV2 materially improves field utility while preserving robustness across sites, habitats, and camera-trap settings.
Hugo Magaldi, Theau d'Audiffret, Etienne Francois Akomo-Okoue +24
UMR7206 Eco-Anthropologie, MNHN, Paris, France; One Forest Vision initiative · Centre National de la Recherche Scientifique et Technologique, Libreville, Gabon · Institut de Recherche en Ecologie Tropicale, Libreville, Gabon +13