Canada may approve an oil pipeline that threatens the world’s most endangered killer whales

Environmentalists are making a last-ditch effort to thwart a Canadian oil pipeline plan that they say will further degrade the fragile habitat of endangered killer whales.

On Saturday, activists will take to the streets of Vancouver, British Columbia, to urge Prime Minister Justin Trudeau to reject the Trans-Mountain expansion, a $5 billion, 620-mile pipeline that would carry oil from the Alberta tar sands to the British Columbia coast for export to foreign markets.

Trudeau’s cabinet has until Dec. 19 to make a final decision on whether to approve Trans-Mountain, which is a project of the Houston, Texas–based energy infrastructure company Kinder Morgan. It would nearly triple the amount of diluted bitumen (a petroleum extract) transported to the Westbridge Terminal in Burnaby, east of Vancouver, from 300,000 to 890,000 barrels per day, creating a nearly sixfold increase in tanker traffic to more than 420 ships per year.

Opponents say the additional shipping traffic would increase the chances of oil spills in the seasonal habitat of the endangered Southern Resident killer whale population, which numbers just 80 individuals, and create exponentially more underwater noise in the already cacophonic, vessel-filled waters.

“We value this population as a sentinel of ecosystem health and the health of our region,” said Misty MacDuffee of the Raincoast Conservation Foundation, which opposes the pipeline. “Approval of this project puts these whales on a trajectory towards a 50 percent chance of extinction.”

Like many conservationists, MacDuffee believes the increased noise from vessel engines and propellers would interfere with the ability of killer whales and other marine species to communicate, navigate, and forage for prey.

“It’s this constant presence of, in some cases, extremely loud noises that are continuously moving through [the whales’] critical habitat,” said MacDuffee. The noise “can occur in the same frequencies they are trying to communicate in. It masks their calls or echolocation as they forage for salmon.”

Shipping noise also decreases the whales’ “acoustic space,” she said. Killer whales are cooperative hunters that communicate constantly to find and prey on fish, as well as to locate each other for mating, socializing, and other critical functions. While their calls can be heard over a range of 12 square miles in waters free of noise pollution, shipping traffic can cut that range by as much as 75 percent, she added.

According to the Canadian government’s 2008 orca recovery strategy, the whales face four key threats: diminished stocks of chinook salmon, their preferred prey; marine pollution, including oil spills from tanker traffic; noise pollution from vessels; and degradation of their habitat.

MacDuffee’s group has joined the Living Oceans Society and the environmental law group Ecojustice in filing for a judicial review of Canada’s National Energy Board, which issued a report supporting the pipeline earlier this year. The groups have charged the board with failing to apply the Species at Risk Act, the Canadian equivalent of the U.S. Endangered Species Act, in its determination.

“The NEB’s report is unlawful and irresponsible,” Ecojustice lawyer Dyna Tuytel said in a statement. “Not only did the report fail to mitigate harm from tanker traffic noise to Southern Resident killer whales, but it also failed to consider other oil tanker adverse impacts that could affect the whales’ critical habitat and prey availability.”

A federal court has yet to rule whether the lawsuit can proceed.

Many analysts expect the government of Trudeau, who was swept into office in 2015 on a platform of environmental stewardship and renewable energy, to approve the pipeline.

“Trudeau seems to be walking backward on many of the commitments and the direction that he indicated to Canadians that he would take,” MacDuffee said.

In an unexpected twist, however, American—rather than Canadian—politics may stymie Trans-Mountain. If President-elect Trump follows through on his vows to resurrect the Keystone XL pipeline project canceled by President Obama, that will allow more Alberta tar sands oil to flow to Port Arthur, Texas, potentially making export via British Columbia unnecessary.