New Underwater Tool Helps Ecologists Identify Fish by Sound

Underwater coral reefs are filled with thumps, pops, and snaps from shrimp and fish, yet ecologists have struggled to interpret these sounds due to the multitude of species present. A new tool developed by the FishEye Collaborative, which includes bioacoustic researchers from the Cornell Lab of Ornithology and Aalto University, has changed this by combining underwater sound recordings with a 360-degree camera to identify individual fish sounds.

This innovative technology, named the Omnidirectional Underwater Passive Acoustic Camera, or UPAC-360, has already identified 46 fish species from the coral reefs of Curacao, with over half of these species previously unknown to produce sounds.

Marc Dantzker, the lead author and Director of FishEye Collaborative, noted that the diversity of fish sounds in a coral reef is comparable to that of birds in a rainforest, estimating that more than 700 fish species in the Caribbean alone produce sounds.

The UPAC-360 allows for spatial audio analysis, enabling researchers to visualize sound direction and correlate it with the 360-degree imagery, ultimately creating a video that reveals which sound comes from which fish.

This extensive collection of fish sounds is now publicly accessible at fisheyecollaborative.org/library, where they can be utilized to train machine learning systems for automatic fish species detection in underwater recordings.

Aaron Rice, a senior author of the study and principal ecologist at the Cornell Lab, mentioned that while building a system like the Merlin Bird ID for oceans is still a future goal, the current sounds serve as valuable resources for scientists and conservationists.

The researchers plan to expand their efforts to other reefs, including those in Hawaii and Indonesia, in the coming months, further enhancing their library of marine sounds for conservation purposes. The findings were published in the journal Methods in Ecology and Evolution, highlighting the potential of acoustic monitoring as a crucial tool for ocean conservation.