A Right Whale Calf Slipped Past a Whole Winter of Surveys
The New England Aquarium said Nov. 2, 2026, that scientists who keep the North Atlantic Right Whale Catalog have identified a calf nobody had recorded, raising the number counted for the 2025–2026 calving season from 23 mother-calf pairs to 24.
The catalog is a photo-identification database that scientists in the Aquarium's Anderson Cabot Center for Ocean Life curate with research groups along the eastern coasts of the United States and Canada. The Aquarium's announcement says that it holds each whale's births, injuries, migration patterns and age, and that the scientists use it to compile a list of mother-calf pairs for every calving season.
Researchers from the Mingan Island Cetacean Study photographed a right whale with a calf near Anticosti Island, Quebec, on Sept. 25, 2026. They shared the images with the catalog team, which spent weeks comparing photographs and sighting records before concluding that this was a new calf, likely born during that season and missed by winter surveys. The mother is a whale the catalog calls Silt, at least 38 years old, and the calf is her sixth.
"Silt was briefly seen in the southeastern U.S. calving grounds in February 2026, so it's possible she had the calf there but snuck away before they were documented together. This is an exciting discovery for us so late in the year," said Amy Warren, a scientist in the Aquarium's Anderson Cabot Center.
The Aquarium calls the 23 pairs counted during the season the fourth-highest count ever. It also calls the species critically endangered, with an estimated population of about 380, and names fishing-gear entanglements and vessel strikes among the threats the whales still face. Silt has survived at least five entanglements, and her 2022 calf died of a severe one earlier this year.
Scientists hope to document the new calf again. The list of the season's mother-calf pairs, with a biography of each whale, is posted on the Aquarium's website.
