Repurposing the internet’s backbone to advance whale monitoring

Bioacoustics researcher Léa Bouffaut, at the Cornell K. Lisa Yang Center for Conservation Bioacoustics, has spent the past several years eavesdropping on the conversations of whales. But instead of using underwater microphones like other marine scientists, she listens by tapping into fiber-optic cables lying on the ocean floor - a powerful tool to aid in marine mammal conservation.

The cables - originally installed for telecommunications or power transmission - also pick up vibrations from sound waves. The technology, known as distributed acoustic sensing (DAS), works by using special instrumentation, sending laser pulses through fiber-optic cables and measuring tiny changes caused by passing sound waves, including whale sounds. By measuring these disturbances, she can detect sounds along many miles of cable where vocalizing whale species leaves a unique fingerprint.

Distributed acoustic sensing using fiber-optic cables essentially turns long stretches of seafloor into dense networks of virtual acoustic sensors that are critical for monitoring whales - details needed to safeguard declining whale populations.