Why the Southern Resident Killer Whales are Dying
The world’s most iconic orcas are on a collision course with extinction, and it’s because of much more than oil tankers
Want to know keep up-to-date on what's happening in Victoria? Subscribe to our daily newsletter:
The world’s most iconic orcas are on a collision course with extinction, and it’s because of much more than oil tankers
The world’s most iconic orcas are on a collision course with extinction, and it’s because of much more than oil tankers
The world’s most iconic orcas are on a collision course with extinction, and it’s because of much more than oil tankers
The Royal B.C. Museum just announced that starting May 15, they are launching a major eight month exhibition on orcas.
On the West Coast, the orcas that typically get the most attention are the Southern Resident Killer Whales, who are arguably among the world’s most famous marine mammals. Photographed almost every day from ferries and whale watching craft, they are the royal family of the Salish Sea; complete with front page headlines announcing births and deaths. But the Southern Residents are also among the world’s most endangered marine mammals. They are losing both weight and numbers, and are poised to be functionally extinct within a century. Below is a breakdown of why these whales are struggling to survive.
The Southern Resident Killer Whales are fish-eaters. While the rest of the world’s 50,000 or so orcas eat everything from sea turtles to seals, the Southern Residents are cursed to have a diet that relies 80 per cent on dwindling stocks of Chinook salmon. Of 13 Fraser River Chinook stocks, only one of them is not considered to be at risk. The situation is similarly grim in the United States, with 10 of 17 of the stocks in Washington, Oregon, and California at risk. Chinook are also shrinking in size, trending towards younger and smaller fish; forcing Southern Residents to expend more energy and time hunting in order to get their fill. What’s more, Southern Residents are competing with a whole web of other forces trying to get their cut of Chinook. In addition to commercial fisheries, whales have to contend with hungry harbour seals. In Puget Sound alone, harbour seals ate through 8.6 million Chinook in a single year. At the same time, Southern Residents were only estimated to have eaten 83,200 Chinook.
Without enough Chinook to eat, Southern Residents are getting noticeably skinnier, particularly among the very females who should be giving birth to the next generation. A shocking 2013 study out of Washington State’s Centre for Whale Research found that one quarter of all Southern Residents they found were badly emaciated, even to the point of having “peanut heads,” which happens when whales lose so much weight that the fat behind the cranium disappears and an indent is visible between the head and the body. Of 11 whales found by the researchers to be alarmingly skinny, eight belonged to J-pod, the pod that spends the most time in Victoria waters. Two of those J-podders reportedly died shortly after observation. This past May, J17 and her daughter, J53 were photographed by the U.S.-based National Oceanic and Atmospheric Administration. Both females were concerningly thin. J50, another female, is also presumed dead.
In the early part of the 20th century, non-Indigenous fishermen and whalers aggressively hunted Salish Sea killer whales to eliminate fishing competition. Starting in 1964, whales faced a new threat: Live capture. In that year, the world’s first captive killer whale, a Southern Resident named Moby Doll was exhibited in Vancouver harbour. After surviving a harpoon lance, Moby Doll was towed back to Vancouver and placed in a makeshift pen managed by the Vancouver Aquarium. The docile orcas so captured the world’s imagination that more than 40 Southern Residents were subsequently lost to captivity between 1964 and 1973.
Southern Residents also have the misfortune to share their habitat with one of the busiest marine waterways on the continent. Although activists have recently alleged that oil tankers added by the Trans Mountain expansion will serve as the death warrant to the Southern Residents, the reality is that those tankers would only represent a marginal increase to the vast flotilla of vessels already packed into the Salish Sea. Today, over half of the shipping activity in Canadian waters occurs off the coast of B.C., with much of that concentrated in the Salish Sea. On average, one large ship crosses the Salish Sea every hour of every day, 24 hours a day, 365 days a year, with three transits per hour at peak times. Worst of all, many key shipping lanes coincide with the Southern Residents’ crucial summer foraging areas in Haro Strait, Boundary Pass, Georgia Strait, and the Strait of Juan de Fuca.
When Southern Residents come to the Salish Sea between May and September to feed on chinook, they are nearly always within 400m of a boat during daylight hours. This constant proximity to boats not only handicaps the whales’ ability to hunt, but it often injures them through collisions. A boat strike was the suspected cause of at least one of the six SRKW deaths in 2016, and of three recorded strikes that involved Southern Residents between 1998 and 2006, at least one was fatal.
Vessel traffic also creates underwater noise, which, in the northern Pacific, has been doubling in intensity every decade for the past 60 years. Killer whales communicate vocally and use echolocation to hunt, so a passing ship can disrupt their lives just as badly as an unmuffled motorcycle blasting past an outdoor wedding. At high speeds, boats can drown out any Southern Resident within 14 kilometres. In the noisiest areas, Southern Residents may lose up to 97% of their communication range. A study commissioned by the Port of Vancouver found that the vessels doing the most damage to orcas were large vessels such as container ships, ferry boats, and tugs. Not only do they crank out lots of ambient noise, but their frequencies overlap with those used by killer whales, effectively “jamming” the animals ability to talk and move around.
Whale watching vessels, which have largely contributed to making the Southern Residents into international celebrities, may ironically be helping to wipe them out. Another Port of Vancouver study found that the noise generated by whale watching boats limits the distance at which orcas can hear salmon by 5 to 34 per cent.
Southern Residents spend their entire lives literally swimming in the various toxic runoffs from Vancouver, Victoria and Puget Sound. So much so, that orcas’ fatty tissues are packed with traces of pesticides, flame retardants and other industrial chemicals. These contaminants come from runoff and wastewater – and from chinook, who are themselves packed with pollutants when they become meals for an orca. When tested for one specific poison, polychlorinated biphenyl, Southern Residents were found to carry unhealthy levels in their bodies. Having blubber packed with pollutants is particularly dangerous when food is scarce. All the aforementioned Southern Residents losing weight are needing to feed off their fat stores, which is delivering an extra powerful dose of accumulated pollutants into their system.
A study of Southern Residents hormone levels between 2008 and 2014 determined that an incredible 69 per cent of detected pregnancies ended in miscarriage, stillbirth, or death of the calf soon after birth. Seven calves were born in 2015, but between 2016 and 2018, not one Southern Resident calf survived. The year 2018 was particularly tragic; one female, J35, carried her calf’s body with her for more than two weeks in an apparent display of mourning after it died shortly after it was born. All these failed pregnancies seem to be a direct response to the bleak conditions of the Southern Residents. Stressful surroundings and a lack of food are prompting the bodies of the Southern Residents to refuse to produce a new generation; a biological phenomenon known as “reproductive suppression.”
What’s more, all these failed pregnancies are proving dangerous to the mothers. Of the failed pregnancies between 2008 and 2014, half occurred late in gestation, increasing the risk of infection due to unsuccessful or incomplete spontaneous abortion. This was the cause of death for an orca called J32 in 2014. Lack of food appears to be the primary reason for the low birth rate, with high contamination levels also playing a role. Of the calves that do survive, meanwhile, most are male–another blow to the long term ability of the Southern Residents to reproduce. Of 31 calves born between 1998 and 2018 whose sex could be determined by researchers, only eight were female.
The Trans Mountain pipeline certainly wouldn’t help the Southern Residents. In the case of an oil spill, there is no marine mammal response plan. Meanwhile, more heavy vessels in the Salish Sea would only add to the populations’ dwindling ability to communicate. But all these factors would only accelerate the demise of a population that has been declining in numbers since 2011.
Southern Residents have been endangered in Canada since 2001 and in the U.S. since 2005. Haro Strait and Boundary Pass, two narrow passageways through the Gulf Island, have been designated “critical habitat” under the Species at Risk Act (SARA) since 2009. But these theoretical protections have not done all that much to increase Chinook stocks or decrease noise pollution. The Southern Resident Recovery Strategy and Action Plan, released in 2008 with many strategies still not started, places more emphasis on research and monitoring than on regulating threats. The Oceans Protection Plan is similarly focused on research rather than mitigation.
This year has seen more federal and local action than previous years. The Canadian government placed limits on the recreational and commercial Chinook fishery. The Port of Vancouver is attempting underwater noise reduction in the whales’ critical habitat, including ship slowdowns in Haro Strait and Boundary Pass. Barges and tugs are asked to move south out of known feeding areas, and the port even offers discounts to vessels employing noise reduction technology. But these are all voluntary measures. Canada has no regulations regarding underwater noise levels. Europe, a jurisdiction that actually does police marine noise levels, would find Canadian waters to be too noisy.
There are also efforts to simply keep boats away from the orcas. Interim sanctuary zones at Swiftsure Bank and near Pender and Saturna Islands are no-go zones for boats. As of June 1, vessels must keep 400m away from whales and whale watching boats must obtain a permit to approach closer.
However, none of these measures have been able to boost the amount of Chinook in the water, which remains the primary factor killing off the Southern Residents. Since 2016, the SRKWs have lost nearly 10 per cent of their number. According to the Center for Whale Research, there are currently 76 whales, including the newest addition to J-pod – the lowest numbers since 1984. Fewer than 30 whales are reproductively capable. Absent drastic reductions in marine noise levels and the reappearance of historic numbers of chinook salmon, there is no reason to believe this trend won’t continue.
As mentioned above, the main reason the Southern Resident Killer Whales are particularly vulnerable to extinction is because their diet is dependent on Chinook. For the world’s other orcas who eat a diverse diet of seals, seabirds, penguins narwhals, sharks and even the occasional swimming deer, the future generally looks bright.
So why don’t the Southern Residents simply try eating something else? The simple answer is that they can’t. For the same reason that a human society based on fishing would struggle with having to become hunters, the Southern Residents aren’t that good at killing anything without gills. The Southern Residents move in larger pods than other orcas, and they’re also much chattier and prone to frolicking. Both of these factors have allowed them to successfully intimidate other orcas who enter the Salish Sea, but it also makes them poor hunters. Moving in big, loud, boisterous groups is fine for fish-eaters, but it scares away almost anything else.
And that’s one of the most tragic things about the ongoing saga of the Southern Residents. Their fate is being decided in part by a trait that is familiar to any human: Culture. One of the most remarkable things about orcas is that, just like humans, they move in groups with distinctive languages, diets, traditions and rituals.
Humans are killing the Southern Residents because they’ve become accustomed to a world with on-demand salmon, pollutant-filled cities and heavily trafficked waterways. The Southern Residents may not forgive what humans have done to them, but they may understand our inability to change in the face of grave consequences.