Abstract
The future productivity of pelagic ecosystems and fisheries globally remains uncertain due to a lack of data on mid-trophic mesopelagic micronekton communities. Here, we demonstrate that integrating readily available autonomous profiling floats with autonomous echosounders enables vertically resolved abundance estimates of mesopelagic micronekton communities, a platform we are naming the “Sonophore”. This successful demonstration is a first step towards addressing critical data gaps identified by fisheries management, earth system and ecosystem modelling communities. With planned engineering enhancements, this platform offers a scalable solution for rapid, cost-effective, year-round monitoring of the planet’s largest vertebrate (but deeply uncertain) biomass. The platform is specifically designed for long-term monitoring of remote and spatially extensive oceanic habitats of the global ocean, without the need for large, expensive research vessels.
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Data availability
The dataset generated during the current study are available in the CSIRO Data Access Portal, https://doi.org/10.25919/1gkd-6r28.
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Acknowledgements
The work was supported under the collaboration agreement between the Pacific Community and CSIRO to implement the Climate Science for Ensuring Pacific Tuna Access grant (ACT-0103048) provided to the Pacific Community by the New Zealand Ministry for Foreign Affairs and Trade under the New Zealand Aid Programme.
Funding
Open access funding provided by CSIRO Library Services. Authors from The Pacific Community, CSIRO and Aqualyd were funded through the Climate Science for Ensuring Pacific Tuna Access grant (ACT-0103048) provided to the Pacific Community by the New Zealand Ministry for Foreign Affairs and Trade under the New Zealand Aid Programme.
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R.D., P.J. and G.M. designed and built the Sonophore and executed the field surveys. G.M., P.J. and R.D. analysed the data and prepared Figs. 1 and 2. R.D., H.P., G.M., C.D. and S.N. wrote the main manuscript text. All authors contributed intellectually and reviewed the manuscript.
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Downie, R.A., Jansen, P., Macaulay, G.J. et al. Sonophore enables autonomous observation of micronekton communities in the ocean twilight zone.
Sci Rep (2026). https://doi.org/10.1038/s41598-026-41581-5
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DOI: https://doi.org/10.1038/s41598-026-41581-5
Keywords
- Twilight zone
- Micronekton
- Biogeochemical cycles
- Pelagic ecosystem
- Climate change
- Marine acoustics
- Environmental monitoring
Source: Ecology - nature.com
