Oil tankers: a killer for whales

The National Energy Board recommended approval of the Trans Mountain expansion knowing the Kinder Morgan project would jeopardize the survival of the Southern Residents.

Southern Resident killer whale mother and juvenile.

Photo by National Oceanic and Atmospheric Administration.

The 29th anniversary of the Exxon Valdez oil spill quietly came and went a few weeks ago. The lack of fanfare was ironic, as that disastrous event is more relevant than ever to the coast of British Columbia.

The spectre of Kinder Morgan’s Trans Mountain expansion, and accompanying increase in dilbit-laden tanker traffic, looms heavily over B.C.’s endangered Southern Resident killer whales.

To gain insight into what the Southern Residents would face if a large oil tanker spill were to occur in the Salish Sea, one only needs to look back at the deaths suffered by Alaska’s killer whales nearly three decades ago after the Exxon Valdez grounded on Bligh Reef, spilling more than 11 million gallons of crude oil into Prince William Sound.

Following the Exxon Valdez oil spill, the mortality rate in two pods of Prince William Sound’s killer whales skyrocketed. While 33 percent of the AB resident population and 41 percent of AT1 transient population disappeared within a year of the spill, most of the carcasses of the 22 missing whales were never accounted for. Both resident and transient pods were documented surfacing in the oiled waters, one of which (the AT1 transients) were photographed at the stern of the Exxon Valdez while it was still leaking thousands of gallons of oil into Alaskan waters.

The National Energy Board recommended approval of the Trans Mountain expansion knowing the Kinder Morgan project would jeopardize the survival of the southern residents.  Tweet This!

The timing and magnitude of missing whales directly following the spill, plus the known exposure, suggests that oil was the cause of death. Scientists have hypothesized that these killer whales died from inhaling highly toxic oil vapours as they swam through and surfaced in the spilled oil.

Unfortunately, many of the whale mortalities were breeding or young females. In the case of the transient population, the loss of the females has meant no new births in nearly three decades. The transient pod is considered functionally extinct, as it will be gone when the remaining individuals die.

Back in the Salish Sea, Southern Resident killer whales are already threatened by declining salmon stocks, physical and acoustic disturbance from vessel traffic, high toxic-contaminant accumulation, and continued inaction by the federal government. Like Prince William Sound’s killer whales, this small population is at a heightened risk of extinction. When small populations experience random events such as food shortages, disease or oil spills, the loss of individuals (especially reproductive females) can have dire consequences.

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In the Raincoast report Our Threatened Coast: Nature and Benefits in the Salish Sea, we overlaid the Southern Residents’ critical habitat (important areas where they feed and raise their young), with the results of Kinder Morgan’s oil-spill scenario near Turn Point at the northern end of Haro Strait, a body of water that flows between southeastern Vancouver Island and the U.S. San Juan Islands. Kinder Morgan’s model is based on fall weather conditions and only runs for 15 days. Notably, experience from the Exxon Valdez oil spill was that oil travelled away from the accident site at Bligh Reef for at least 56 days.

A large oil spill near Turn Point has a 95 percent chance of exposing Resident killer whales to the oil slick if they are anywhere near Haro Strait or the eastern end of the Juan de Fuca Strait. There is a 60 percent chance of an oil slick covering a 3,800-square-kilometre area centred at Turn Point. Haro Strait has been one of the most routinely travelled areas in the Salish Sea for Southern Resident killer whales.


Raincoast used Kinder Morgan’s modelled probabilities of where oil would go within 15 days of a tanker accident at Turn Point in northern Haro Strait to produce the shaded black to grey areas. We then overlaid this with the critical habitat (in red) of Southern Resident killer whales. The darkest areas on the map (high probability of oil slick) are some of the heaviest used areas by these whales.

As expert interveners, Raincoast provided evidence to the National Energy Board on the substantial threats that the Trans Mountain expansion presents to Southern Resident killer whales. Our evidence included a population viability analysis, subsequently published in the peer-reviewed journal Scientific Reports, which not only looked at oil-spill risk, but also examined the effects of increased noise from Kinder Morgan’s oil tankers on the ability of the southern residents to successfully catch their prey.

The study found that even without an oil spill, the noise alone from the increase in tanker traffic substantially increased the likelihood of extinction. Significantly, none of the parties presenting evidence to the NEB disputed this. Moreover, Kinder Morgan, the NEB and the federal government also agreed that even without an oil spill, the noise from oil tankers presents significant adverse effects on these whales that cannot be mitigated.

The National Energy Board recommended approval of the Trans Mountain expansion knowing the Kinder Morgan project would jeopardize the survival of the Southern Residents. Perhaps in an attempt to avoid the fact that this might violate Canada’s Species at Risk Act, the NEB made an 11th-hour decision to arbitrarily truncate the Trans Mountain project at tidewater (Burnaby terminal), excluding impacts to killer whales from the environmental assessment.

Raincoast’s position in ongoing litigation is that the NEB violated Canada’s Species at Risk Act.  Tweet This!

In January, Ecojustice — on behalf of Raincoast, David Suzuki Foundation, Georgia Strait Alliance, Natural Resources Defense Council, and World Wildlife Fund Canada — petitioned the Ministers for emergency protection for the whales under the federal Species at Risk Act. The ‘imminent threat’ announcement made this week by the federal government is a response to our petition.

Federal Minister of Fisheries and Oceans Dominic LeBlanc and Minister of Environment and Climate Change Catherine McKenna have announced that endangered Southern Resident killer whales face ‘imminent threats’ to their survival and recovery. The Ministers also announced that fisheries closures in key Southern Resident foraging areas would be implemented.

While welcome news, the measures announced by the federal government only partially address concerns over food availability and disturbance to the whales. The fisheries closures need to include all the key foraging areas recommended by killer whale scientists that the government missed, and ensure a minimum number of Chinook salmon return to spawn.

These closures in key feeding areas also need to exclude whale watching in order to reduce noise and disturbance from boats that make it hard for killer whales to hear, communicate and catch salmon. The government’s announcement also means that the ministers are now legally obligated to recommend that the federal Cabinet issue emergency protections for the whales.


Chris Genovali is executive director of Raincoast Conservation Foundation, Misty MacDuffee is Raincoast’s wild salmon program director, and Paul C. Paquet, PhD, is Raincoast’s senior scientist. Versions of this article were first published in the Victoria Times Colonist and the Vancouver Province.

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