Exploring the potential of distributed acoustic sensing for fish bioacoustics

Abstract

Underwater soundscapes are critical indicators of marine ecosystem health, but traditional passive acoustic monitoring with hydrophones is spatially limited and logistically challenging for long-term observations. This study investigates the potential of distributed acoustic sensing (DAS) to overcome these limitations. A field trial was conducted using a bespoke fiber-optic cable deployed off the coast of Monaco, focusing on three sound-producing Mediterranean species: Ophidion rochei , Sciaena umbra , and Epinephelus marginatus , all known for their distinct acoustic signatures. DAS recordings reveal species-specific patterns consistent with documented behaviors, and are validated by co-located hydrophone recordings. Due to its high sensor density, DAS allows the isolation and localization of individual sounds over tens of meters. The results demonstrate that DAS can detect and locate fish sounds under real-world conditions, while also assessing ambient noise levels. The DAS setup in this experiment may not match the performance of conventional hydrophones, but the approach’s potential for dense, continuous, and low-maintenance monitoring, particularly where suitable fiber-optic infrastructure already exists, points to a promising complementary role in marine conservation in the context of climate change and biodiversity loss.