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A wave glider for passive acoustic monitoring of cetaceans and anthropogenic sources in the central Mediterranean Sea

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Abstract

Passive acoustic monitoring has become a widely used method to study cetaceans, especially for populations facing escalating threats from noisy human activities, including shipping traffic, fishing industry and marine constructions. Here, we conducted a study using an autonomous surface vehicle to explore the distribution and acoustic behavior of cetaceans and to characterize anthropogenic sound sources in the central Mediterranean Sea. A wave glider equipped with a single-towed acoustic recorder was deployed from 13th September 2022 to 3rd March 2023. The recording yielded 19,115 files of 460s each (approximately 2 TB), a third of which was kept for a preliminary analysis based on spectrogram visualization and audio listening. The results showed that nearly half of the dataset contained delphinid signals (Delphinidae), followed by sperm whales (Physeter macrocephalus) and fin whales (Balaenoptera physalus), with notable hotspots in the southern Tyrrhenian and the Ionian Sea. Moreover, the almost continuous detection of anthropogenic sources highlighted the widespread acoustic impact of human activities in the area. These findings demonstrate the value of passive acoustics in the use of autonomous vehicles as a versatile tool for large-scale and long-term monitoring, offering a promising approach to support conservation efforts for vulnerable species while advancing strategies to mitigate human impacts on marine ecosystems.

Data availability

Acoustic data is available on request to the corresponding author.

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Acknowledgements

This research would not have been possible without the work of many colleagues at the Stazione Zoologica Anton Dohrn. In particular, the authors would like to thank Robin Caron, Florence Rappin and Gerardo Sorrentino. During the writing of this manuscript, S.F. was supported by the Stazione Zoologica Anton Dohrn and the University of Turin through a SUSTNET PhD scholarship (n°39-033-31-DOT21BX3F7-8932). The PhD funder had no role in study design, data collection, or data analysis. Part of the work conducted for this study by F.C., S. F. and A. E. was carried out within the framework of the projects PRIN DIVES (CUP: C53D23003430006, Grant Assignment Decree n°1015-07/07/2023) and PRIN PNRR KNOWhale (CUP: C53D23007160001, Grant Assignment Decree n°1370-01/09/2023), funded by the European Union – Next GenerationEU – under the National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.1, Calls for tender No. 104 and 1409 published on 2022 by the Italian Ministry of University and Research (MUR). This work was also supported by NRRP, Mission 4, Component 2, Investment 1.4, Call for tender N. 3138 of 16/12/2021, rectified by Decree n.3175 of18/12/2021 of MUR, funded by the European Union – NextGenerationEU (Project code: CN_00000033, Concession Decree No. 1034 of 17/06/2022adopted by the MUR, CUP: C63C22000520001, project National Biodiversity Future Center – NBFC).

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Author notes

  1. Sara Ferri and Anaëlle Evrard contributed equally to this work.

Authors and Affiliations

  1. Department of Marine Animal Conservation and Public Engagement, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy

    Sara Ferri, Anaëlle Evrard, Livio Favaro & Francesco Caruso

  2. Department of Life Sciences and System Biology, University of Torino, Via Accademia Albertina, 13, 10123, Torino, Italy

    Sara Ferri & Livio Favaro

  3. Department of Research Infrastructures for Marine Biological Resources, Stazione Zoologica Anton Dohrn, Via Po’ 25c, 00189, Rome, Italy

    Simonepietro Canese & Augusto Passarelli

  4. Department of Biology and Evolution of Marine Organisms, Sicily Marine Centre, Stazione Zoologica Anton Dohrn, Villa Pace – Contrada Porticatello 29, 98167, Messina, Italy

    Teresa Romeo

  5. National Biodiversity Future Center, Piazza Marina 61, 90133, Palermo, Italy

    Simonepietro Canese, Teresa Romeo & Francesco Caruso

  6. National Institute for Environmental Protection and Research, Via dei Mille 46, 98057, Milazzo, Italy

    Teresa Romeo

  7. University of Gastronomic Sciences, Piazza Vittorio Emanuele 9, 12060, Pollenzo, Italy

    Silvestro Greco

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  1. Sara Ferri
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Contributions

Conceptualization, F.C, S.F. A.E.; methodology, F.C, S.C., A.P, S.F., A.E.; data analysis, F.C., S.F., A.E.; writing—original draft preparation, S.F., A.E.; writing—review and editing, F.C., L.F; supervision, F.C.; project administration, S.C., A.P., T.R; funding acquisition, T.R, S.G. All authors have read and agreed to the published version of the manuscript.

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Francesco Caruso.

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Ferri, S., Evrard, A., Canese, S. et al. A wave glider for passive acoustic monitoring of cetaceans and anthropogenic sources in the central Mediterranean Sea.
Sci Rep (2025). https://doi.org/10.1038/s41598-025-32142-3

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  • DOI: https://doi.org/10.1038/s41598-025-32142-3

Keywords

  • Autonomous vehicles
  • Mediterranean basin
  • Underwater acoustics
  • Marine mammals
  • Cetaceans’ distribution
  • Marine conservation

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