Cape Cod Canal closes to vessel traffic as endangered right whales move through

A North Atlantic right whale fed on the surface of Cape Cod Bay in 2018. Officials closed the Cape Cod Canal on Sunday, March 5, 2023, following reports of a group of right whales passing through the waterway.Michael Dwyer/Associated Press

The Cape Cod Canal was closed to vessel traffic until at least Monday morning as a group of endangered North Atlantic right whales began to move through the canal on Sunday, causing a backup of boats waiting for passage, according to the US Coast Guard and the Massachusetts Environmental Police.

Environmental Police were notified by the US Army Corp of Engineers at 10:30 a.m. that a juvenile right whale was heading west in the canal toward Buzzards Bay. Once it reached Massachusetts Maritime Academy, the whale turned back toward Cape Cod Bay, where it again reversed direction and started back to the west, Environmental Police said in a statement.

The V-shaped blow of a critically endangered North Atlantic right whale, this one at the west end of the Cape Cod Canal. Mariners keep a sharp eye out! pic.twitter.com/eF4vnhpAHc

— Hyannis Whale Watch (@WhalesCapeCod) March 6, 2023

An hour later, the Center for Coastal Studies reported three additional right whales feeding off the canal’s east end, near the entrance from Cape Cod Bay, according to Environmental Police. In response, the Army Corps of Engineers shut down the canal to vessels, the agency said.

Dr. Michael Moore, a biologist with the Woods Hole Oceanographic Institution, said reports of right whales in the canal happen every few years, but rarely do they reach the middle of the waterway.

He said the whales could have been drawn into the canal as they were hunting for food.

“Perhaps they know it is a short cut around Cape Cod, but we don’t really know,” Moore said in an e-mail Sunday. “They change their migration patterns as climate disruption causes their prey to shift location.”

An Environmental Police spokesperson said the closure caused a backup of commercial vessels waiting to pass through the canal.

The Army Corps of Engineers did not return messages seeking more information Sunday.

The North Atlantic right whale is among the world’s most endangered species of large whales, with a population of just 340, according to an October report from the North Atlantic Right Whale Consortium.

“It is really good that the Army Corp of Engineers and the US Coast Guard are willing to close it for these highly endangered animals,” Moore said. “Of course it is a major disruption to shipping schedules. The conservation community is really grateful.”