North Atlantic right whale mother, Caterpillar (#3503), right, surfaces with her first calf in April in Cape Cod Bay, Mass.CENTER FOR COASTAL STUDIES (NOAA PERMIT 25740-02)
The critically endangered North Atlantic right whale population reached 384 animals in 2024, a 2-per-cent increase from the previous year, according to the latest estimate.
The update, released Tuesday by the North Atlantic Right Whale Consortium, shared at its annual meeting in New Bedford, Mass., marks the fourth consecutive year of slow growth for the species. More than 450 researchers, conservationists, government officials and industry representatives from the U.S. and Canada gathered for the two-day meeting to assess the status of one of the world’s most endangered large whales.
Entanglements in fishing gear and vessel strikes are the leading threats to the species. While scientists welcome the positive trend, and the absence of any detected deaths so far in 2025, they say recovery depends on sustained management efforts on both sides of the U.S.-Canada border – efforts that face mounting challenges from regulatory delays.
“With small population increases year to year, we still need strong protective measures for continued growth,” said Heather Pettis of the New England Aquarium, who chairs the consortium. “We don’t want to take our foot off the gas when it comes to management and conservation efforts.”
The 2024 estimate, calculated by aquarium scientists with the National Oceanic and Atmospheric Administration (NOAA), includes a margin of error that puts the population somewhere between 375 and 394 whales, up from last year’s recalculated range of 373 to 380.
Philip Hamilton, a senior scientist at the aquarium, said the modest growth follows a decade of decline triggered by climate-driven changes in feeding habitat that left whales vulnerable in unprotected areas and led to an “unusual mortality event” that began in 2017 and continues today.
“It took approximately a decade for both whales and managers to adapt,” Mr. Hamilton said. The current growth rate matches what the population achieved in the 1980s and 90s before the decline.
The fact that four known mothers gave birth this year at four-year intervals – when whales are healthy, they can reproduce every three to four years beginning at about age 10 – suggests some whales are successfully adapting. “They’re doing their part, and we have to continue to do ours,” Mr. Hamilton said.
Among this year’s 11 calves are the offspring of whales whose life histories illustrate both resilience and vulnerability.
Grand Teton (#1145), at least 44 years old, gave birth to her ninth calf in January, one of only a handful of females to do so.
Caterpillar (#3503) gave birth to her first calf at age 20 – more than a decade later than normal. She was struck by a vessel at age two, leaving a large scar on her flank.
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The 2024 estimate includes 72 reproductive females, while the aquarium estimates another 45 females aged 10 to 20 could join their ranks. Four of those became first-time mothers at an average of 16 years of age, in the 2025 calving season.
“We’d like to see more first-time moms at younger ages, which says they’re healthy enough to carry a pregnancy to term,” Prof. Pettis said.
Mr. Hamilton said the mothers carry an enormous burden, travelling the eastern seaboard and crossing a gamut of danger. “The future of the species really is resting on their broad backs.”
Caterpillar (#3503), right, was struck by a vessel at age 2, leaving a large scar on her flank. Now 20, the first-time North Atlantic right whale mother surfaces with her calf, making the species’ distinctive V-shaped blow.Center for Coastal Studies/Supplied
Coming off a difficult 2024 that saw five right whale deaths, 16 entanglements and eight vessel strikes, this year has brought welcome relief: one new entanglement without attached fishing gear and one vessel strike detected so far.
But scientists caution that reduced detection doesn’t necessarily mean fewer injuries. “Detecting entanglements requires two things to align: people to be looking and whales to be present in those times and locations where they’re looking,” Mr. Hamilton said.
Half of last year’s entanglements weren’t detected until the latter half of the year, including four in December. “The news is definitely better than last year,” Mr. Hamilton said. “We just don’t know what the final story will look like once the year is over.”
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Fisheries and Oceans Canada has yet to release its whale-safe gear strategy, originally scheduled for the spring.
In the U.S., a government shutdown has suspended NOAA’s fisheries monitoring, stock assessment and survey work since Oct. 1.
Meanwhile, congressional legislation prevents NOAA Fisheries from implementing additional right whale protection measures until 2029 – a decision that effectively froze new regulations during a critical period for recovery.
The U.S. also withdrew its proposal to amend vessel speed rules in January after pushback from mariners and lawmakers.
Prof. Pettis emphasized that protecting a species whose range spans two countries requires sustained collaboration. “You cannot protect the animal in one country and not the other,” she said.
Despite the positive trajectory, Mr. Hamilton stressed that the population remains critically vulnerable. “There are fewer right whales alive today than are going to be people at this conference,” he said. “I am so relieved that the numbers are going up slowly, but that relief does not make me feel any less urgency.”
This story is part of a series produced in partnership with the Pulitzer Center’s Ocean Reporting Network.