On Thursday, officials from Transport Canada and the Department of Fisheries and Oceans announced new widespread speed limits in the shipping lanes around Anticosti Island in the Gulf of St. Lawrence to protect the endangered right whales.Moira Brown/Cabot Center at the New England Aquarium
As climate change warmed the deep waters off the coast of Nova Scotia and Maine, endangered North Atlantic right whales headed out to sea in greater numbers searching for plankton. Four of those whales showed up dead this week, bringing the total number this month to six.
Federal officials said at a press conference on Thursday that at least one whale was struck and killed by a vessel as they announced stricter shipping rules designed to protect the approximately 400 remaining whales. But scientists say the real threat may be climate change, which has scattered the whales’ food source and left them travelling into new habitats searching for sustenance.
“We have a lot of skinny whales,” said Tony Lacasse, spokesperson for the New England Aquarium, which tracks the species. “They found more food in the Gulf of St. Lawrence. … But not only is that habitat new and a risk to right whales – it’s a new problem for government officials and fishermen."
With this year’s deaths, the total number of North Atlantic right whales found dead in the Gulf of St. Lawrence since 2015 climbed to 21. Necropsies have shown that many of them died after being hit by vessels or becoming tangled in fishermen’s lines. At least three of the whales that died this year were female, a double blow for the population.
On Thursday, officials from Transport Canada and the Department of Fisheries and Oceans announced new widespread speed limits in the shipping lanes around Anticosti Island in the Gulf of St. Lawrence to protect the whales. Parts of the gulf have been closed to fishermen, whose vertical crab or lobster lines can entangle the whales, keeping them from surfacing until they drown.
Many North Atlantic right whales used to congregate in the summer off the northeastern coast of the United States where copepods – a type of plankton the whales prefer to eat that thrives in colder water – were plentiful. The U.S. and Canadian governments have implemented rules protecting the whales in that area since the 1990s.
But around 2010, the whales began spending less time in their summer feeding grounds. They began swimming farther in search of food with many making their way into the Gulf of St. Lawrence.
“Probably prior to 2014 [the Gulf of St. Lawrence] would have a handful of sightings a year,” Mr. Lacasse said. “It was nothing compared to what’s happened in the past three years [because] now there are hundreds of whales using that area.”
A recent study conducted by a coalition of maritime experts and published in Oceanography magazine connected recent changes in the movement of North Atlantic right whales to rising ocean temperatures off the Northeastern United States. The deep waters in the Gulf of Maine are warming faster than any other part of the ocean affecting the copepods the whales love to eat. They dispersed farther in search of food making them “more vulnerable to ship strikes and gear entanglements,” according to the study.
In 2017, 12 North Atlantic right whales were found dead around the Gulf of St. Lawrence, a statistic that devastated scientists who have seen the population of whales take a steep dive in recent years. Two of those whales died after they became entangled in fishing lines, five were likely struck by vessels and five died of unknown causes.
Since then, federal authorities have implemented no-go zones where fishermen aren’t allowed to set traps and the measures seemed to work – in 2018, there were no deaths in Canadian waters.
The mitigation measures can be a headache for some fishermen, according to Martin Mallet, executive director of the Maritime Fishermen’s Union.
“It’s been tough on fishermen,” he said. “Some fishermen have had issues getting their quotas but at the end of the day we think that the measures have enabled us to get out of the way of the whales.”
Experts couldn’t determine how Wolverine, a young male found earlier this month, died. On June 20, Punctuation, a mature female who had raised eight calves, was found dead – struck by a vessel. Another male named Comet, an unnamed female and one whale yet unidentified were found dead this week. Another was found drifting off the Gaspé Peninsula Thursday.
Necropsies will be performed by scientists on some of the other deceased whales in the coming days to determine how they died.
“I’ve been studying this population for over 30 years. I’ve seen many of these whales as calves growing up. Punctuation is one we’ve been watching since 1981. … So it’s heartbreaking," said Philip Hamilton, a research scientist at the Anderson Cabot Center for Ocean Life.
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