A North Atlantic right whale and its calf break the ocean’s surface for a breath of fresh air. Photo courtesy of Florida Fish and Wildlife Conservation Commission

Climate Change Forcing North Atlantic Right Whales Migration

Fewer than 350 North Atlantic right whales exist. Warming temperatures in the Gulf of Maine have put the endangered species in new peril.

By Michayla Savitt

1/26/2023

Climate change, which has touched every aspect of nature, now has the dwindling ranks of  the North Atlantic right whale on the move, new research shows.

A recent study published in Scientific Reports found the whales have migrated from the fast-warming Gulf of Maine to an old feeding ground in the New England Shelf — posing a challenge to conservation efforts.

The North Atlantic right whale has been endangered since 1970. But with fewer than 350 of the whales remaining, they’re now considered critically endangered. Policies exist along the U.S. East Coast to reduce vessel speed, and seasonally close commercial fisheries where the whales congregate in an effort to shield them from potentially fatal boating strikes and fishing rope entanglement. But experts say this new research is alarming because if the whales are spending time in areas without proper protection, they may be in greater peril.

“All of these policies are put in place to protect right whales,” said Dr. Erin Meyer-Gutbrod, with the School of the Earth, Ocean and Environment at the University of South Carolina. “But if right whales are somewhere else, and we’re not protecting their new habitat, then the policies are completely ineffective.”

Orla O’Brien, an associate scientist at the Center for Ocean Life at the New England Aquarium and lead researcher for the study, noted large shifts in right whale migration over the last decade.

She and her New England Aquarium colleagues observed Southern New England waters from a plane over 80 times from 2013 to 2019 to count the whales just south of Nantucket and Martha’s Vineyard. The right whale can grow to be over 50 feet, and has a black body with white marks on their head, which is used to identify them in tracking population.

Researchers concluded that more right whales were found in the southern New England waters between 2017 and 2019 than between 2013 and 2015, indicating that the species may be changing migration patterns.

“They’re abandoning some habitats that they used to very reliably return to every year to feed,” O’Brien said. “And then they’re finding new habitats that are cropping up where researchers didn’t find them before.”

Scientists first detected a decline in the right whale population in 2010. This is partially tied to a decrease in birth rates because of the availability of one of their primary prey: copepods, a kind of zooplankton. A female whale will migrate to where there’s food so they can build up enough fat to carry their calf to term, said Sean Hayes, Chief of NOAA Fisheries.

O’Brien further pointed to warming temperatures in the Gulf of Maine — where the right whales used to spend a lot of time — as a factor in food availability.

“So if their main source of prey, copepods, relies on certain temperatures for different life stages, and all of a sudden that’s changing, then that is going to stream upwards to right whales as well,” she said.

Meyer-Gutbrod, who was not involved in the study, noted that southern New England waters used to be just a stopover area as right whales went between feeding sites. In the winter and spring, whales traveled from the southeastern U.S. to Cape Cod. Come summer, they went up to the Bay of Fundy and Roseway Basin in Canada.

She emphasized that this research shows a need for further monitoring in the New England shelf to track habitat location changes. In particular, warming temperatures that affect zooplankton availability can drive right whales to seek food elsewhere.

Meanwhile, there are plans to build the first large-scale commercial wind farm in 2023 in the New England shelf. This could lead to further displacement, behavior disruption, and stress for the right whale due to the noise and obstacles caused by construction. Study researchers noted this challenge in their report. They recommended further aerial surveys and efforts to identify and protect conservation areas that might be vital to the right whale, and other marine mammals.