As their population plummets, right whales are on verge of extinction

“Given the low population numbers … it is essential that we work together to protect every North Atlantic right whale in order to avoid extinction for this endangered species,” Colleen Coogan, the agency’s marine mammal take reduction team coordinator, wrote in an e-mail to members of a federal advisory board tasked with finding ways to reduce risks to the whales.

Since January 2019, there have been 11 right whales found dead, with four others seriously injured and likely to die.

Of the 13 whales born in the past two years, one was recently found dead and another is presumed to have died earlier this year after being hit by a vessel only hours after being born. It’s believed twice as many right whales perish each year than are found dead.

Coogan said the latest population estimate is considered preliminary. It will be reviewed further before being completed in next year’s federal assessment of the species.

“This preliminary number is lower than expected, in part, because updated photo-identification data now indicate the previous year’s estimate was too high,” she said.

Last year’s population estimate should have been 383, not 412, Coogan said.

The lowered estimate raised deep concerns among environmental advocates who have spent years trying to protect the whales.

“If we don’t act quickly, right whales are headed rapidly toward extinction,” said Sharon Young, marine issues field director of The Humane Society of the United States. “It is appalling to think this nation would permit the extinction of a whale species in our waters. It’s time to stop talking and take action.”

Kristen Monsell, oceans legal director at the Center for Biological Diversity, called the new estimate “heartbreaking and horrifying.”

This month two right whales were found severely entangled in fishing gear, one off the coast of Nantucket, she said. They are unlikely to survive.

“The Fisheries Service must take immediate, bold action to get vertical lines out of key right whale habitat areas,” she said. “The species can’t afford more deadly delays and half-measures.”

The Humane Society and the Center for Biological Diversity, as well as other groups, sued the Fisheries Service, arguing the agency violated the Endangered Species Act by failing to reduce the risk of right whales becoming entangled in millions of lobster lines in the Gulf of Maine.

Last spring, a federal judge ruled in their favor. The lines, which extend from traps on the seafloor to buoys on the surface, have in recent years been the leading cause of the whales’ deaths. Many have also died as a result of vessel strikes.

The judge gave the Fisheries Service until the end of May 2021 to issue new regulations to protect the whales. The agency has repeatedly delayed releasing the regulations, which are likely to mandate that lobstermen reduce the number of buoy lines they use.

Since its population hit a modern peak in 2011 at 481, about 218 right whales have died, an average of 24 a year, Coogan said. In that time, there have been only 103 births.

Scientists at the Fisheries Service say the species is unlikely to avoid extinction with as few as one death a year.

It’s unknown how many right whales are alive today, but Michael Moore, director of the Marine Mammal Center at the Woods Hole Oceanographic Institution, said there are likely to be fewer than 366.

“We only get to actually examine the tip of the right whale trauma iceberg,” he said. “The rest go AWOL.”

Since 2017, 31 right whales have been found dead and 11 have been seriously injured.

“The outlook is grim if we do not act today,” said Erica Fuller, a senior attorney at the Conservation Law Foundation. “We know human activities are decimating this population. What will it take for federal fishery managers to finally take action?”

In her letter, Coogan said the Fisheries Service is considering whether it needs to modify its regulations to reduce vessel strikes and plans to issue regulations to reduce entanglement risks. It wasn’t clear when that would happen, and officials at the Fisheries Service declined to comment.

Coogan also said the agency is working with fishermen and others to test fishing gear that doesn’t require ropes to lift traps from the ocean floor. But environmental advocates say the Fisheries Service isn’t acting quickly enough.

In a letter to Wilbur Ross, the secretary of the US Department of Commerce, which oversees the Fisheries Service, several advocates this week called on regulators to use emergency authority to close areas to fishing.

“These new figures ... add an exclamation point to this emergency,” said Peter Baker, director of northern oceans conservation at The Pew Charitable Trusts.

David Abel can be reached at david.abel@globe.com. Follow him @davabel.