Tracking the North Atlantic right whale
When the North Atlantic right whale seemingly vanished from its spring/summer foraging grounds near the Gulf of Maine in 2010, scientists and conservation groups were alarmed and mystified.
“After 30 years of coming to the Bay of Fundy, they almost completely abandoned that habitat,” says Kimberley Davies, an associate professor in the Department of Biological Sciences at the University of New Brunswick (UNB).
The slow-swimming mammals, measuring up to 52 feet, weighing 140,000 pounds and living up to 70 years, had been hunted almost to extinction. Even after industrial whaling ended in the early 1970s, their population continued to decline. Numbering in the low hundreds, they were considered a species at risk.
It took five years, says Davies, to track them down. A scientist who studies the North Atlantic right whale’s foraging and prey, she had a hunch that the baleen whales had shifted their habitat in search of a new food supply.
By this time, Davies was working with the Ocean Tracking Network (OTN), a global aquatic animal tracking, data management and partnership platform headquartered at Dalhousie University. Supported since 2008 by the Canada Foundation for Innovation, OTN has pioneered the remote offloading of acoustic data using ocean-going marine autonomous vehicles called gliders.
As one of Canada’s 16 national research facilities, says Sara Iverson, scientific director at OTN, “we’ve established the country’s largest glider program.” The underwater drones gather data, track ocean conditions and carry equipment that detects and monitors the movement of marine animals.
Fred Whoriskey, executive director of OTN, adds that the gliders are a cost-effective approach to monitoring large areas that present a “mass reduction of carbon footprint” compared to other surveillance methods.
“There’s a huge increase in safety because they are unmanned and can function in any weather conditions,” he says. ”They can travel the open ocean 24/7 at any depth, at any time.”
Deploying the gliders in Canadian waters, “we discovered the animals in the southern Gulf of St. Lawrence,” says Davies. Further investigation determined that warming of the waters in the Gulf of Maine had led to declines in the whales’ food source. They’d headed north where food is more abundant.
While this explained why the whales had left and where they went, the scientists were confronted by another dire problem, she says. “They started to be killed or injured by fishing gear entanglement and ship strikes in very high numbers.”
In 2017, the death of 17 North Atlantic right whales shook both the scientific community and the public. It triggered governments and other agencies to accelerate research, monitoring and protection of the species, which had now been listed as critically endangered.
In 2021, OTN announced that it had extended its North Atlantic right whale monitoring project for five years in partnership with UNB and Transport Canada. The additional funding of $3.6-million allowed OTN to purchase a state-of-the-art G3 Slocum glider, supplementing the fleet of gliders operated and maintained by Dalhousie’s Coastal Environmental Observation Technology and Research (CEOTR) group.
The Slocum glider, explains Iverson, features a hydrophone developed at the Woods Hole Oceanographic Institution in Massachusetts. “It is outfitted with a mobile transceiver that can detect animals with an acoustic tag. In the case of the right whales, we use ‘passive acoustic’ monitoring. Basically, these special hydrophones listen for whale calls,” she says. “We can relay information of whale presence in real time or near real time to ships to basically alter their course, slow their speed or to create closures.”
The addition of the new glider is critically important, says Whoriskey. “The more gliders we can add, the better job we can do covering areas of high probability of risk — in the fishing regions, in the shipping lanes — in order to avoid fatalities.”
Hansen Johnson, a PhD student at Dalhousie University who studies baleen whale acoustic and habitat ecology, appreciates that the gliders are collecting “huge amounts of continuous information about whale presence and habitat.” As part of his research, Johnson has developed an interactive map tracking right whale distribution.
The gliders have “really expanded our observational capacity in a profound way,” he says.
Davies is hopeful that through “continuous monitoring and mitigation of threats, by introducing new and better tools and technologies to alleviate risks, and with ongoing effort on all fronts, the North Atlantic right whale will soon be back on the road to recovery.”
This story was originally published on Friday, November 19, 2021, as part of the “Excellence in Research and Innovation” feature in The Globe and Mail that marked the CFI’s 25th anniversary.