Gray whales went extinct in the Atlantic 200 years ago. One was just seen south of Nantucket

Researchers from the New England Aquarium saw a gray whale swimming 30 miles south of Nantucket late last week — more than 200 years after the species went extinct in the Atlantic Ocean.

Orla O’Brien, a researcher for the New England Aquarium, saw the whale while flying over it, and noted it’s distinctive lack of a dorsal fin and mottled gray and white skin. But said she couldn’t believe her eyes at first.

“We know what a gray whale is supposed to look like,” she said, “and you're looking at it and you're like, ‘I know this is a gray whale, but there's no way that this could be a gray whale, right? Because they just don't live in the Atlantic.’”

She theorized that it came to local waters after embarking on a exceptionally long journey. Gray whales are regularly seen in the Pacific Ocean, swimming off the coast of California and Alaska.

This whale most likely continued traveling north around Alaska then turned east when it hit Canada. It would have through the Northwest Passage in the Arctic Ocean, which connects the Atlantic and Pacific.

The Northwest Passage used to be filled with sea ice limiting the species’ range, but that was before climate change.

“As waters have warmed and the Arctic has less ice in it  — or not 100% coverage everywhere — it means that passages have opened up where an animal could actually swim all the way through,” O’Brien said. 

It’s extremely rare to see a gray whale off the East Coast, but in the last 15 years, researchers have seen gray whales in Atlantic and Mediterranean waters five times. One was even seen off the coast of Florida last December.

“Based on photographs from that sighting,” O’Brien said, “we believe this is actually the same animal, which is very cool, and also the most reasonable explanation for there being two sightings, as opposed to two separate whales.”

She said these sightings of gray whales in the Atlantic are a reminder of how quickly marine species respond to climate change, if given the chance.