Undersea internet cables could help save endangered orcas: Scientists

By Esra Tekin

ISTANBUL (AA) - At daybreak in the Salish Sea, a team of scientists aboard a research barge meticulously deployed more than a mile of fiber-optic cable into the cold, deep waters below, according to a media report.

Illuminated only by headlamps, the researchers extended the cable from the rugged shoreline of San Juan Island to the seafloor -- a critical habitat for the endangered Southern Resident orca population.

Their goal is to transform the hair-thin internet cables into a vast underwater listening network that could revolutionize marine conservation.

Using a technology known as Distributed Acoustic Sensing (DAS), researchers from the University of Washington are experimenting with turning standard fiber-optic cables typically used for transmitting data into continuous, real-time underwater microphones.

These cables could capture the clicks, calls and whistles of passing whales, helping scientists understand how the animals respond to ship traffic, food scarcity and climate change.

If successful, this could unlock a global ocean monitoring network using the 1.4 million kilometers (870,000 miles) of fiber-optic cables already crisscrossing the ocean floor.

“We can imagine that we have thousands of hydrophones along the cable recording data continuously,” said Shima Abadi, professor at the University of Washington Bothell School of STEM and the UW School of Oceanography.

“We can know where the animals are and learn about their migration patterns much better than hydrophones,” Abadi said.

Unlike traditional hydrophones, which listen from a single location, DAS technology turns the entire cable into a distributed sensor.

That means researchers can detect sounds over a wide area and determine not just what was heard, but where it came from and which direction the animal was heading.

The technology has already been proven effective with large baleen whales.

In a previous study off the Oregon coast, the research team successfully captured the low-frequency calls of blue and fin whales using existing telecommunications cables.

But orcas — especially the Southern Resident population — pose a new challenge. Their vocalizations operate at much higher frequencies, and DAS has not yet been tested at that range.

To find out, the team recently deployed about one mile of fiber-optic cable in the Salish Sea -- a critical habitat for the Southern Resident orcas. If the system can reliably detect their sounds, it would mark a major step forward in non-invasive ocean monitoring.

The timing of the project is crucial. In January, the High Seas Treaty enters into force, allowing the creation of new marine protected areas in international waters. But despite the growing urgency to protect marine biodiversity, scientists still lack basic data on how human activity affects many ocean species — and where protections are most needed.

“One of the most important challenges for managing wildlife, conserving biodiversity and combating climate change is that there’s just a lack of data overall,” said Yuta Masuda, director of science at Allen Family Philanthropies, which helped fund the project.

If the experiment in the Salish Sea succeeds, scientists envision a future where the ocean itself can be continuously and passively monitored — using cables that are already in place beneath nearly every ocean.

“It’s like turning the internet into an ear to the sea,” one researcher said, Euronews reported.