Ocean next to an iceburg. There are three whales in it

Whale watching from space

Scientists are deploying an unlikely tool in the bid to track and monitor whale populations: satellites.

Narwhal (a) and beluga (b) individuals detected from panchromatic WorldView-3 satellite images at a 1:265 scale. Image credit: DigitalGlobe, Inc

As described in a new paper in PLOS ONE, a team of researchers from whale-watching technology company Whale Seeker analysed images from the WorldView-3 (WV3) satellite, a very high-resolution (VHR) Earth-observation satellite that’s hovering in orbit 670km up, to track populations of two Arctic whale species, the narwhal (Monodon monoceros) and the beluga whale (Delphinapterus leucas).

Monitoring whales in the frigid waters of the Arctic has often been troublesome for scientists because the area is remote, difficult to access, and because whales tend to disperse across vast distances with broad migratory patterns.

“Monitoring cetaceans using satellite images has huge advantages, not only for wildlife but also for the humans studying them,” says Bertrand Charry, one of the principal researchers on the study.

“As the lead biologist at Whale Seeker I’ve experienced first-hand the harsh environmental conditions of the Arctic during field studies. Obtaining imagery using aerial technology (the most common method) is highly dependent on weather patterns, it is dangerous for the researchers, expensive, and can disturb the animals in their habitat.”

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So, satellite imagery offers a powerful way to track these species from the comfort of the office or laboratory, rather than through risky aerial flights over remote locations or complicated and invasive tagging operations.

The researchers searched through the satellite’s images for signs of two major populations: the beluga whale population of the Cumberland Sound, an Arctic waterway in Nunavut, Canada; and the narwhal population of Baffin Bay, also in Nunavut. The team found that 12 images taken between 2017 and 2019 showed a total of 292 beluga whales and 109 narwhals across the locations.

While satellite imagery has been used to track larger whale species in the past, the authors say this is the first time it’s been proven to reliably pick up mid-sized whales, like the narwhal and the beluga.

“This was made possible by the advancements in satellite technology over the last few years,” Charry says, which include “accessibility and extremely high-resolution levels, which facilitated the work of the scientists processing the imagery”.

The authors say the method is still in its infancy: it still requires clear weather, and can only detect whales at or near the surface. But they argue that space-based solutions to population monitoring offer a safer, simpler alternative to the costly and dangerous methods of the past.

“Our hope is that scientists are encouraged to keep up with the latest technological developments and see the potential in collaborating with companies in the field,” Charry says. “With an increase in Marine Protected Areas worldwide, we need better tools to monitor vast areas, safely.”