Whale watching just went next level.

Purnima Ratilal, an engineering professor from Northeastern University, has a developed a new device that classifies and monitors whales in real time over thousands of miles, using underwater microphones.

The new tech uses an array of 160 microphones to listen to a section of ocean the size of Tennessee. Researchers used resulting data to distinguish between the calls of eight whale species — blue, fin, humpback, sei, minke, sperm, pilot, and killer — and track their locations. The findings were published this week online by Nature.

“[Ours] is the only technique that can instantaneously monitor marine mammal and fish populations over very large areas,” she tells The Atlantic.

The scientists came to a surprising conclusion. Whales divvy up the feeding grounds of the ocean, much like the plant-eaters of African grasslands. It’s unknown how these boundaries are imagined or enforced.

Traditional methods of researching whales involve listening to whale sounds on a small scale, or visually watching and tracking individual pods. This new technology, dubbed passive ocean acoustic waveguide remote sensing or POAWRS, provides a better macro picture of whale habitats than has ever been seen before.

Certainly whales hold many secrets left to be discovered, and this will help researchers peer into their world.

Photos via Wang et al, 2016. Nature, Jim Kravitz / Flickr