Two dozen endangered right whales spotted off Martha’s Vineyard

Two dozen North Atlantic right whales were seen off Martha’s Vineyard on March 10, according to the New England Aquarium, prompting temporary speed restrictions in the area to reduce the risk of vessel strikes.

The federal restrictions recommend a speed of 10 knots or less for all vessels, according to the National Oceanic and Atmospheric Administration, which in a separate aerial survey last week made 39 right whale sightings.

Such restrictions are crucial as vessel strikes are a leading cause of death among North Atlantic right whales, a critically endangered species, said Orla O’Brien, an associate scientist at the New England Aquarium. There are fewer than 350 right whales in the world, researchers estimate.

“Being able to alert mariners in the area to the presence of whales and remind them that they need to keep a lookout and go slowly is really helpful,” O’Brien said.

Another major threat to right whales is becoming entangled in fishing gear, such as nets, ropes, and lines from lobster traps, O’Brien said. It’s common for the whales to carry gear on their bodies for months or even years, leading to serious health issues.

One adult male right whale spotted by the New England Aquarium March 10 was a victim of gear entanglement, O’Brien said. The whale, named Nimbus for a cloud-like spot on its chin, was spotted off the coast of Georgia in January by the state’s department of natural resources, O’Brien said.

The department sent a disentanglement squad that successfully removed most of the line he was tangled in, except for a few stubborn pieces that remained in his mouth, O’Brien said.

By the time Nimbus swam to New England, where he was spotted by the New England Aquarium, Nimbus was completely free of any fishing gear, O’Brien said.

“It was cool and a positive thing to see this whale continuing on and still feeding and hopefully recovering,” she said.

Right whale sightings in New England this time of year aren’t unusual because areas like the Nantucket shoals are teeming with copepods, a krill-like species that right whales feed on, O’Brien said. The whales spotted March 10 were seen feeding, socializing, and even engaging in behaviors associated with mating, she said.