A North Atlantic right whale spotted in Irish waters last year has been identified on the North American coast.
While conducting an aerial survey on November 19th, observers from the Centre for Coastal Studies (CCS) Right Whale Ecology Program sighted a North Atlantic right whale off the coast of Boston.
Scientists in the New England Aquarium’s Anderson Cabot Centre for Ocean Life confirmed it had previously only been seen in Donegal Bay, Ireland, in July 2024, as reported by the Irish Whale and Dolphin Group (IWDG).
There have been rare instances of known North Atlantic right whales from the western Atlantic travelling to the eastern Atlantic and back, but the IWDG says this appears to be the first documented case of a whale initially sighted in the eastern North Atlantic and later seen in the western North Atlantic.
The sighting suggests that historical North Atlantic right whale habitats may still hold value and that right whales continue to search widely for suitable habitat, scientists say.
CCS researchers Ryan Schosberg and Annie Bartlett were conducting the centre’s second aerial survey of the 2025-2026 season in Massachusetts Bay when they made the sighting.
“About four-and-a-half hours into the survey, we broke from our trackline to document a group of humpback whales about 23 nautical miles east of Boston,” they said.
“While photographing the humpbacks, we were surprised to spot a lone right whale feeding at the surface nearby. We quickly diverted to photo-document the whale, our first right whale sighting of the season,” they said.
“The first sighting of the year is always exciting, but we didn’t yet realise just how remarkable this one would turn out to be,” said Schosberg.
North Atlantic right whales are critically endangered, with a population estimated at just 384. Every year, CCS documents roughly half of the entire right whale population in and around Cape Cod Bay.
This means it is unusual for the centre to encounter an individual it doesn’t recognise or can’t quickly find in the greater North Atlantic Right Whale Catalogue.
CCS researchers quickly realised this whale didn’t match any known right whales and reached out to colleagues at the Anderson Cabot Center for Ocean Life at the New England Aquarium, the curators of the aforementioned catalogue, for their assessment.
Read the IWDG website here
