Two Endangered Right Whales Spotted Entangled Southeast Of Nantucket

Two critically endangered North Atlantic right whales were spotted entangled south of Nantucket earlier this month, and marine officials say one - a juvenile male - is expected to die from its injuries.

The two whales were seen on Dec. 9 by a NOAA Fisheries aerial survey team approximately 50 miles southeast of the island. Entanglement response teams did not mount a response after the initial sighting, NOAA said, because of the time of day and the distance of the whales from shore.

“North Atlantic right whales continue to be entangled at levels that could push this critically endangered species to extinction," said Amy Knowlton, senior scientist at the Anderson Cabot Center for Ocean Life at the New England Aquarium. "It is distressing that multiple generations of right whales have been affected by the devastating harm of entanglements, which is resulting in deaths, health declines, and slower reproductive rates."

The population of critically endangered North Atlantic right whales has shown a slight increase, according to the latest estimate released in late October 2024 by the North Atlantic Right Whale Consortium. The group pegged the global population of North Atlantic right whales at 372 individuals, including 12 calves born in 2023, in what the consortium described as a "heartening" increase since the population dipped to 358 four years ago. But entanglements - like the two observed south of Nantucket earlier this month - and ship strikes remain the leading causes of right whale fatalities.

The first whale spotted on Dec. 9 was identified as a juvenile male (pictured above). He was first seen as a calf in 2021 and most recently seen gear-free in Cape Cod Bay in April 2024, NOAA stated. This whale has a thick line that passes once across his head and once across his back. After reviewing the entanglement, NOAA Fisheries biologists made a preliminary determination that it meets the Unusual Mortality Event criteria as a “serious injury” case, signifying that the whale is likely to die from this injury.

The New England Aquarium stated that the juvenile male's family has a "long and sad history of entanglement." He was born in 2021 to a female named “Binary" and is the third of her three calves. Binary has suffered three entanglements, including a case in which she got entangled in gillnet gear while her 2011 calf was at her side. Fortunately, she was able to shed the entangling gear.

The second whale spotted with an entanglement earlier this month off Nantucket was identified as an adult female who was first seen as a calf in 2011. She was most recently seen gear-free approximately 50 miles off the coast of Long Island, New York, in July 2024. This whale has two lines exiting the left side of her mouth, with both lines extending a half to two-thirds of the way down the body. After reviewing the entanglement, NOAA Fisheries biologists have made a preliminary determination that it meets the Unusual Mortality Event criteria as a “morbidity” (sublethal injury) case.

"As conditions permit, we will work with authorized responders and trained experts to monitor the whales," NOAA stated. "We will further document the entanglements and determine if entanglement responses will be possible."

The two right whales south of Nantucket are the 149th and 150th individuals documented in the ongoing North Atlantic right whale Unusual Mortality Event, which includes dead, seriously injured, or otherwise health-compromised whales.

Mariners are encouraged to report sightings of entangled, injured, or dead whales:

• Greater Atlantic Marine Mammal Stranding Hotline for Maine to Virginia: (866) 755-6622
• Southeast Marine Mammal Stranding Hotline for North Carolina to Texas: (877) WHALE-HELP ((877) 942-5343)
• U.S. Coast Guard: VHF Channel 16

If safe, and from the legally required 500-yard distance, please take photos or video and note the GPS coordinates to share with authorized responders.