Narwhals ‘arctic oceanographers’

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Scientists have enlisted some supremely qualified recruits to retrieve important data on one of the most remote and inhospitable places on Earth. And all these recruits want is a nice fish dinner.

That’s because they are narwhals, a deep-diving arctic whale famous for the males’ long, spiral tusk.

University of Washington marine biologist Kristin Laidre and colleague Mads Peter Heide-Jorgensen of the Greenland Institute of Natural Resources have equipped three narwhals with sophisticated satellite transmitters to send data on water temperatures in ice-clogged seas between Greenland and Canada.

“In a way, we’ve converted these animals into oceanographers,” Laidre said this week.

“We’re not only learning about their ecology and biology, but we’re collecting data that can be useful for bigger-picture climate change questions.”

The whales are collecting data about Baffin Bay, their winter habitat between northeast Canada and Greenland. Baffin Bay joins with the Arctic Ocean to the north and west and the Atlantic Ocean to the south via Davis Strait.

Laidre said there had been essentially no such data on this region from wintertime, when it is covered in ice and impassable to ships. It is an important link in global ocean circulation and a good place to detect ocean changes in due to climate change.

But the whales thrive in these winter conditions. They dive to depths of 1.1 miles (1,800 metres) to feed on Greenland halibut, a deep-water flatfish living on bottom of Baffin Bay.

The devices placed on their backs record water temperatures at various depths and track narwhal movements and diving behaviour, adding to the understanding of these elusive whales. The devices transmit 400 readings a day.

‘FANTASTIC DATA’

“If you can attach an instrument to a whale that’s going down to the bottom of Baffin Bay and coming back up again