Government keeps watch on latest entangled North Atlantic right whale off Gaspé Peninsula

The latest right whale discovered entangled off Quebec's Gaspé Peninsula is a male, known by the number 3245.

Staff with the New England Aquarium say they last saw him in April, when he was still swimming free swim in Cape Cod Bay. But on Monday, the 15-year-old whale was discovered entangled by a Fisheries and Oceans Canada plane surveying an area of the Gulf of St. Lawrence off Percé.

The plane has since returned to relocate him and is "assessing the situation and monitoring extremely closely," Vance Chow, a Fisheries department spokesperson, said in an email to CBC News Tuesday.

"The entanglement of a right whale is an extremely difficult and distressing situation."

Chow said the government is also upholding its pause on disentanglements, which went into effect in July after the death of New Brunswick whale rescuer Joe Howlett.

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Howlett was killed in an accident just as he freed a right whale tangled up in fishing rope in the Gulf of St. Lawrence.

Long-lived animals

Marianna Hagbloom, a research assistant with the New England Aquarium, said number 3245 was born in 2002.

He has regularly been seen since in all the major right whale habitats, from the southeast U.S. to the Bay of Fundy.

The last time he was seen in the Gulf of St. Lawrence was in 2015. Staff at the aquarium also saw him this past spring during their biopsy field work in Cape Cod, she said.

The maximum life expectancy of right whales is unknown, Hagbloom said.

"But we know they can live to be at least 70 years old," she said. "The oldest whale we know of — a female, at least 70 — was killed by a ship strike. But we suspect they are long-lived animals."

At least 13 right whales have been found dead this year off the coasts of Canada and New England. The whales are among the rarest marine mammals in the world and number no more than 500.

Entanglement in fishing rope and collisions with ships are the suspected causes of most of the deaths, but necropsy results are not yet available.