Death of North Atlantic right whale illustrates difficulty of protecting the endangered mammals

Scientists on Feb. 1 perform a necropsy on the right whale calf that washed up on Martha's Vineyard. It was the first right whale that died while entangled in Maine lobstering rope, though officials have not confirmed whether the rope caused the mammal to die. Thomas Humphrey/Vineyard Gazette

North Atlantic right whale No. 5120 didn’t live long enough to get a nickname.

For over a year, rescuers tried to disentangle ropes from the female calf. But despite several attempts, they could not remove the 100 feet of fishing rope digging into her tail.

The 3-year-old right whale washed up dead last month on a Martha’s Vineyard beach. And the federal agency charged with conserving the endangered species confirmed – for the first time – that the rope wrapped around her was from Maine lobstering gear. Experts are still determining the definitive cause of death.

Grief for the animal has rolled in like a swell of waves. Many are mourning the suffering 5120 experienced in her short life. But with 5120, another glimmer of hope that the right whale population can survive has died, too.

“It’s not just the heartbreak of losing her. It’s the heartbreak of losing what she could have added into the population in her own calves, and then their calves and so on,” said Heather Pettis, a research scientist with the Anderson Cabot Center for Ocean Life. “Any loss of an animal, a right whale, is devastating. But when you lose a female, it’s that much worse because of the potential that you’re also losing with her.”

A DWINDLING POPULATION

The North Atlantic right whale population has been dwindling for decades. There are only 360 of the mammals left, according to data from the National Oceanic and Atmospheric Administration. And fewer than 70 are breeding females.

The federal agency contends that vessel strikes and entanglements from fishing gear are to blame for the species’ decline. Confirmed vessel strikes and fishing-gear entanglements have caused 78% of the 123 incidents that have killed or seriously injured right whales since 2017, according to NOAA’s right whale tracker last updated on Wednesday.

Experts are expected to announce a final conclusion about 5120’s cause of death in the coming weeks.

Less than two weeks after her body was cut open and examined, another young female has died. NOAA reported on Thursday that the carcass of a different calf, born last year, was floating off the coast of Georgia.

NOAA has pushed for new regulations that lobstermen fear would bar them from using traditional trap-and-buoy lobster gear that requires vertical lines, or ropes dangling in the ocean, though officials cannot draft new whale-protection rules until 2029.

Maine lobstermen contend that a transition to alternative technology would gut the state’s historic lobster industry as they know it.

The regulations have been a source of contention, lawsuits and disagreements between federal regulators and Maine’s congressional delegation.

Amid the debates, Maine lobstermen have asserted no known right whale death or entanglement has been definitively linked to their fishing gear – something they can no longer say.

Experts say confirming that link on Wednesday was the result of an extraordinary set of circumstances.

There were slim chances that 5120 would wash up on shore and even slimmer chances that she’d still have rope attached to her body, with markings linked to Maine’s lobster fishery.

But 5120’s actual life and death were as ordinary as can be these days, said Scott Landry, the director of the Center for Coastal Studies’ Marine Animal Entanglement Response Program.

Over 85% of right whales have been entangled in fishing gear at least once, NOAA data shows.

THE JOURNEY THAT LED TO HER DEATH

North Atlantic right whale No. 5120 was born during the 2021 calving season as an only child to 17-year-old Squilla, No. 3720. She moved up and down the East Coast, most likely using Maine’s waters as a thruway, rather than a habitat, Landry said.

In August 2022, three months after her last sighting, aerial surveyors found the calf with nearly 300 feet of rope attached to the base of her tail and trailing behind her body.

No. 5120 as a calf, 7 months old, in the Gulf of St. Lawrence, Canada in July 2021. Courtesy of New England Aquarium & Canadian Whale Institute/DFO Canada SARA permit

Multiple attempts were made to disentangle the rope from her body. But the rescue missions became much harder after the Center for Coastal Studies found the calf in January 2023 without the 170 feet of rope trailing behind her. Disentanglement attempts are far easier when there’s a trail of rope for the grappling hooks that rescuers throw to latch onto.

The center’s Marine Animal Entanglement Response team spent nearly 20 hours chasing the calf over the course of three days that month. But after one unsuccessful throw, it’s a near guarantee that the whale won’t settle down enough for the next throw to latch.

With the loss of that 170-foot trail of rope, researchers and rescuers were left with watching 5120 gradually deteriorate through pictures captured during different sightings. When her carcass washed up on the beach, it was clear the entanglement had taken a toll.

“The injury is horrific. She spent 17 months with a line wrapped around her flukes tightly digging into that flesh,” said Pettis, who had been tracking the calf’s development since she was first sighted. “She was incredibly thin. The rope had really dug in and tissue had grown over that, so the line was deeply embedded.”

The calf’s tail was also covered in whale lice, indicating that the wound was open and active, she said.

HUMAN IMPACT

These conservationists, researchers and rescuers are tasked with one over-arching goal: to save the North Atlantic right whale from extinction.

Landry puts all his energy into depersonalizing each whale and its rescue missions. There’s no other way he can do this work. He calls it a “cold and mathematical” approach.

The 20,000-pound right whale was towed to the northern harbor of Martha’s Vineyard in January before it was trucked to another part of the island for a necropsy. Ray Ewing/Vineyard Gazette

But the death of a female calf who should have had a long life of breeding is a distinct kind of loss.

After becoming sexually mature at 10 years old, female right whales can start breeding calves every four years. NOAA reports that sexually reproductive right whales are only giving birth every 6 to 10 years, however. Squilla was 17 years old when she gave birth to her first and only calf, 5120.

And it’s still hard for some not to get swept up in the emotion. No. 5120 spent most of her life navigating up and down the Atlantic coast entangled in rope cutting deeper into her skin by the day.

“Imagine someone had put a collar on a puppy and never adjusted the collar as the puppy grew,” Landry said. “That rope was now mostly inside of the whale’s body. The whale is literally growing into the rope.”

It’s challenging to tune out human emotion when watching a whale like 5120 slowly fade away.

“When you see an animal like this entangled and injured at such a young age, and then have to grow through that, and, and bear witness to the injury progression and know that there’s got to be a level of suffering involved, that’s hard to watch,” Pettis said. “I don’t know if her case is any more heartbreaking than other females that we’ve seen. But I can’t stop thinking about the suffering … that’s a hard pill to swallow.”

This story has been updated to clarify that the National Oceanic and Atmospheric Administration plans to issue new regulations for lobstering but that officials cannot draft new whale-protection rules until 2029.