Cause of death

Report finds vessel strikes, entanglement continue to plague North Atlantic right whale

A report released on Wednesday confirms that vessel strikes most likely caused nearly half of the deaths last year of nine endangered North Atlantic right whales in the Gulf of St. Lawrence.

The Marine Animal Response Society and the Canadian Wildlife Health Co-operative produced an incident report that covers necropsy investigations for five of the whales found dead between June and July 2019, in which vessel strikes were the most likely cause of death of four of the marine animals.

The cause of death of the fifth could not be determined.

Necropsies could not be performed on the remaining four whales, and their cause of death remains unknown.

“It’s a very complicated subject, and I know there are many groups working very hard on figuring out how we can be more invested in created regulations that are meant to save whales,’’ Dr. Laura Bourque, a wildlife pathologist at the Atlantic Veterinary College in Charlottetown, told The Guardian. “We have no idea if we’re touching all of the whale deaths. There is a very good chance this is just the tip of the iceberg.’’

Other significant findings include four additional live right whales observed to be entangled in fishing gear in Canadian waters during the same time period. One of the whales was later discovered dead off the eastern seaboard of the United States. Experts in the U.S. who examined the body confirmed the injuries and probable cause of death were due to entanglement.

In 2017, an unprecedented 12 right whales were found dead in the Gulf of St. Lawrence. Of these, seven deaths were determined to be due to vessel strikes and entanglement in fishing gear.

With only about 400 remaining and the population in decline, the North Atlantic right whale is one of the world’s most endangered large whale species.

Bourque said the right whale is a migratory species and tends to be in Atlantic Canadian waters in the summer. Between 2015 and 2017, they were found in the Bay of Fundy, then seemed to shift to the Gulf of St. Lawrence.

The right whale has been a federally-protected species for the past 20 years, yet Bourque said the mortality rate is increasing at an alarming rate.