Nearly 80 endangered North Atlantic right whales spotted off coast of Cape Cod

Many of the whales are near the Cape Cod Canal, which will likely be closed if they enter it

The National Oceanic and Atmospheric Administration had 39 right whale sightings March 10.NOAA

Roughly a fourth of all the North Atlantic right whales left on Earth are roaming the waters of Cape Cod Bay — a remarkable sight for any whale species, but particularly one so critically endangered that experts warn they could go extinct within the decade.

A flight crew of four from the Center for Coastal Studies spotted 79 individual whales while aboard a low-flying Cessna Skymaster on Thursday. Inclement weather sent the plane home early, leading experts to believe that number was likely a conservative estimate.

“I would anticipate that we probably have at least 90 to 100 whales in the bay right now,” said Charles “Stormy” Mayo, the director of research for the right whale ecology program at the Provincetown-based center. “It’s quite extraordinary.”

Nearly half of these whales are congregating near the Cape Cod Canal, which remained open Saturday afternoon, but will likely close should any of the whales enter its narrow passage. A similar scenario played out three weeks ago when a right whale swam the length of the canal before turning around.

On Monday, researchers spotted a 41-year-old whale named Spindle and her calf within Cape Cod Bay. Video captured by the Woods Hole Oceanographic Institution shows the young whale suckling as it swims under its mother.

“We are beyond grateful to have been able to witness that and to take such clear imagery of that scene. Hopefully it helps people understand why we are so keen to conserve the species. They are so very special,” said Michael Moore, a senior scientist at WHOI who shot the video.

Calf sightings are particularly meaningful to researchers since right whale deaths now outpace births due to to threats from shipping, climate change, and commercial fishing.

That reality is not lost on members of the Center for Coastal Studies Marine Animal Entanglement Response team, who are currently monitoring a badly entangled 8-year-old right whale in the bay.

The whale, identified as #4545, is a female who was first discovered entangled — with a rope caught in her mouth and multiple wraps around her body and flippers — south of Nantucket in February by the Northeast Fisheries Science Center. On Wednesday, the team removed some 200 feet of rope and attached a small telemetry buoy to facilitate tracking.

Scott Landry, director of MAER said, “this is obviously a difficult situation. We worked very hard for this whale on Wednesday, and she did all she could to avoid us. With the telemetry buoy in place on her entanglement all of our attention will be focused on trying again.”

It isn’t rare to have North Atlantic right whales in Cape Cod Bay this time of year. In March 2021, 89 right whales were spotted in the bay, including three pairs of mothers and babies. They typically migrate south for the winter and return to the bay in early spring.

“The number of overall right whales has only decreased, but every year we see more in Cape Cod. Of course this begs the question: Is Cape Cod actually special, or is it the only bit of ocean left that is half decent for right whales?,” said Mayo.

Mayo lauded state officials in Massachusetts for taking “a really strong approach” to make the Cape a safe environment for right whales.

He pointed to the state’s ban in the area on fixed-gear fishing, including lobster and crab pots and gillnets. The ban — which lasts from February to April — has pitted environmental advocates against fishermen, who claim the restriction puts a devastating burden on the already struggling industry that has long defined New England’s economy. A study published last June in the journal of the Society for Conservation Biology noted that fishing gear entanglements are the leading cause of serious injury and death for right whales.

A few weeks ago, a young right whale entered the Cape Cod Canal and swam nearly its entire 17.4-mile length before turning around. That incident prompted the closure of the canal and brought maritime traffic to a standstill for roughly 12 hours as the whale made its loop.

The canal remained open as of Saturday afternoon, despite dozens of whales congregating near its entrance.

“I don’t think we’re going to see a closure unless there’s a clear report of a whale in the canal. Unfortunately, right now the conditions are not good so we’ll just have to hang on and wait,” said Mayo.

Surveillance flights will also be grounded until conditions improve. A map of right whale sightings, last updated on Friday, shows a smattering of the whales through the entirety of Cape Cod Bay. Some were seen as far north as Scituate, but most congregated off the beaches of Provincetown and Sandwich.

Marine biologist John Chisholm of the New England Aquarium spotted right whales breaching on Friday just yards from the coastline of the Sandwich town beach.

“I can’t help but wonder if future generations will get to see these critically endangered whales or will they look at these photos and videos like we look at the last thylacine images?” he wrote on Twitter.