The short version
- A laser sent down an ordinary telecom cable can pick up whale calls, because passing sound makes tiny changes in the glass fiber.
- This spring the method caught bowhead whales off Alaska for the first time, a harder target than the deep-voiced blue and fin whales it was first tested on.
- A new review by the same researcher says fiber listening still needs standard tests and automated analysis before it can be used for routine monitoring.
Léa Bouffaut, a researcher at Cornell’s K. Lisa Yang Center for Conservation Bioacoustics, has recorded bowhead whale calls on a fiber-optic telecommunications cable for the first time. The work used distributed acoustic sensing, in which instruments fire laser pulses down the fiber and measure the tiny changes a passing sound makes in the glass. In spring 2026, working with the Barrow Whaling Captains Association and the North Slope Borough Department of Wildlife Management, she listened along an existing cable off Utqiaġvik, Alaska, owned by the operator Quintillion. The calls turned up after weeks of combing terabytes of data. Cornell’s release gives no count of calls, cable length or distances.
Bouffaut first caught blue and fin whales this way in 2022, but their calls sit below 100 Hz and are loud. Bowheads and North Atlantic right whales call higher, around 150 to 300 Hz, and more quietly. “Being able to detect bowhead whales on a telecommunication cable is the proof of concept we need,” she said. Her review, published November 9 in Methods in Ecology and Evolution, says routine use still needs two things: tests of how well cables hear different species across different cable layouts, and automated ways to sift the data.
The cables are meant to complement underwater microphones, not to replace them.
