HALIFAX – They are known as the leviathans of the sea — elusive giants that roam the waters of the eastern seaboard, sometimes hidden from scientists’ keen attempts to track them.
The rare North Atlantic right whale was known to have regular haunts off the East Coast, but researchers have struggled to figure out where the hulking mammals go when they’re not there.
Now, technology may be helping crack the case.
Researchers at Dalhousie University in Halifax have been using an arsenal of underwater gliders armed with voice recognition software to search and listen for right whales in the Gulf of St. Lawrence and a long stretch of territory off Nova Scotia.
They have discovered that the endangered whales have been venturing to the Gaspe peninsula in a likely bid to find sufficient food, suggesting the area may be another one of the mammal’s critical habitats.
“That’s definitely one of the big results that’s come out of the project,” said Kim Davies, an oceanographer at Dalhousie.
“We had 46 occurrences of right whale sounds being recorded by the glider on the Gaspe…so we can be pretty confident that they were not using the western Scotian shelf as habitat this year and were using the Gaspe.”
She cautions that there are likely other habitats that they don’t yet know about since the entire population was not in the Gaspe region and were not found in great numbers this year in their usual spots, the Roseway Basin and the Bay of Fundy.
Still, she says the robots are helping to expand their knowledge of animals that were once hunted to near extinction and difficult to track.
The bright yellow gliders have hydrophones that can capture the sounds of several whales — including blue, sei, humpback and grey whales — and determine exactly which species it is while transmitting the data back to headquarters in real time.
The devices can travel thousands of kilometres and stay out at sea for up to four months, quietly collecting data on the marine ecosystem and its inhabitants.
Davies says the idea this summer was to have multiple gliders deployed in different areas at the same time so they could determine if the right whales were using one area over another.
“The gliders fill a key gap in our knowledge,” she said.
The whales’ movements can also be followed on a new website that outlines the bid to find the animals, while letting people see exactly where the whales are.
Sean Brilliant of the Canadian Wildlife Federation is part of the website initiative and says he was amazed by the technology’s ability to readily indicate the whales’ whereabouts and collect water samples to determine such things as the temperature and food is availability.
“I thought that’s amazing that we can just know there’s a group of 70-foot-long mammals swimming off the coast of Nova Scotia right now, so we wanted to share that with everyone,” he said.
“It’s really quite surprising to see how many whales are there all the time.”
The work of trying to figure out where they are is critical to protecting the slow-moving, 60-tonne mammals from their greatest threats — ship strikes and entanglements in fishing gear, says Brilliant.
The population — now pegged at about 520 up from 300 in the late 1990s — are known to travel to Roseway Basin and into the Bay of Fundy in the summer to feed with their calves. Most make the long trek from their breeding grounds off Georgia and Florida, ending up in the bay’s plankton-rich waters around June.
But when most of them didn’t show up in those spots in recent years, scientists launched a robust effort to find them.
“It was an embarrassment of ignorance — we had no idea where these whales were going and how do you search the ocean for whales?” says Brilliant.
“Slowly, but surely we’re starting to understand these animals and see them a bit better… It’s quite an exciting thing.”
The team still has gliders out in the Gulf of St. Lawrence and one getting close to Halifax. It also recently deployed one for the navy’s exercise, Cutlass Fury, to gather acoustic data and help with marine mammal detection.
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