Narwhals have evolved to spend Arctic winters below densely packed ice, where they are safe from killer whales. Photo: Glenn Williams/Wikimedia Commons

From the comfort of your home computer, you can keep tabs on one of the world’s most mysterious creatures in its watery world 1.5 kilometres beneath the sea.

An international team of researchers headed by Fisheries and Oceans Canada (DFO) is tracking seven narwhals that were fitted with satellite transmitters last August off the coast of North Baffin Island. The tags send signals to a satellite 850 kilometres above Earth that relays coordinates in real time back to antennas on the ground.

Scientists are using the information to better understand and protect this at-risk species, which is thought to number 100,000 worldwide, including roughly 80,000 in Canadian waters.

The information is also being used to raise public awareness. Beginning in 2011, the weekly tracking data on the seven narwhals were made available to the public via a website maintained by World Wildlife Fund Canada and DFO.

Known as “sea unicorns” for the male’s ivory tusklike tooth, which can grow up to 2.5 metres long, narwhals are an ice-dependent species; they have evolved to spend the long Arctic winter below densely packed ice, safe from killer whales. Arctic ice cover, however, is melting. By identifying the narwhals’ feeding and calving areas, scientists hope to develop a better understanding of the movement and behaviour of these animals, says Jack Orr, DFO’s project lead for Arctic operations.

According to the tracking data, narwhals spend the winter in central and southern Baffin Bay and northern Davis Strait, diving up to 1.5 kilometres below the surface. This could have important implications for Arctic development.

Down there in the icy darkness, the narwhals are probably feeding on Greenland halibut, says Pete Ewins, the Toronto-based Arctic species specialist with World Wildlife Fund Canada. He and other scientists believe the halibut in this area represent the whales’ main energy source.

“These are the same areas people are starting to explore for oil and gas,” says Ewins. “If you know these areas are important to acoustically sensitive and pollution-sensitive animals for eight months of the year, you want to assess decisions about industrial shipping or hydrocarbon exploration in a smart way.”

In 2007, Canada protected part of this habitat, closing the Greenland halibut fishery on the slope of southern Baffin Bay, a core area where several pods of narwhals spend the winter.

Scientists are also tracking migration routes to the inlets farther north, where narwhals calve, says DFO marine biologist Steve Ferguson. “We can identify which communities they’re passing by and which communities are hunting them,” he says. “We can proportion out the number harvested to make sure it’s sustainable.”

Since the project began in the 1990s, more than 100 narwhals have been tagged. But the cellphone-sized tags — fitted painlessly to the whale’s blubbery dorsal ridge — fall off after 6 to 12 months. So every summer, scientists and hunters camp on Arctic beaches to net and tag more narwhals.

“This is a great example of technology being deployed to get information you wouldn’t otherwise get,” says Ewins. “I mean, who goes out into the sea ice of northern Baffin Bay in the middle of winter, let alone down to 1.5 kilometres?”