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Cast an eye upon Canada’s Pacific coast and it shouldn’t take long to spot its most ubiquitous marine mammal, the harbor seal. At least 100,000 are thought to occupy the coves and nearshore waters along British Columbia’s coast.
You may view seals with wonder, as evidence of a productive marine ecosystem on the doorstep of civilization. Or, just as easily, as a ravenous predator gobbling up the same fish populations sought by humans.
Enter a divisive proposal to cull the seals and sea lions. Enough time has been spent studying the species’ impact on fish stocks, advocates of the cull say: it’s time to cut them back.
In recent decades, only small-scale culls have occurred on both sides of the international border. In 1997 and 1998, Canada authorized the killing of 52 harbor seals on Vancouver Island’s Puntledge River to protect juvenile chinook salmon migrating to sea. Then, in 2020, the United States approved a larger cull of up to 540 California sea lions and 176 Steller sea lions over five years on the lower Columbia River system. The initiative along the Washington-Oregon border is designed to safeguard endangered chinook and steelhead that are returning to spawn.
The cull proposed for British Columbia vastly exceeds these earlier hunts.
University of British Columbia (UBC) professor emeritus of oceans and fisheries Carl Walters is pushing for the slaughter of 50,000 harbor seals and 25,000 Steller sea lions—half their populations on the BC coast. Another 3,000 seals per year would be killed on an ongoing basis to keep the animals in check.
The counterargument to Walters’s proposal is that while seals and sea lions do eat some salmon, there are too many variables at play to predict the outcome of a massive cull. Other factors may be suppressing salmon stocks, too, including ocean warming; hatchery fish competing with wild stocks; and other salmon predators, such as fish, birds, and other mammals—everything from bears to dolphins.
“It may well be that the seals and sea lions are just the first in line at the seafood buffet,” says Andrew Trites, director of UBC’s Marine Mammal Research Unit.
Walters is supported by Pacific Balance Pinniped Society, which represents some Indigenous leaders as well as sport and commercial fishers. He agrees his ideas lack the backing of the majority of Canadian marine mammal researchers, but suggests their opposition has little to do with the facts. Scientists have a vested interest in soliciting money to continue studying the topic rather than supporting action now, he argues.
Scientists’ reluctance to endorse a cull, he says, “is centered on the idea that we need to do more research, that everything is very uncertain, and that the numbers are very iffy, blah, blah, blah.”
The proposal is the latest in a saga that has stretched more than 100 years. In a 1916 story in Vancouver’s The Sun, fishers and canners supported the government’s bounty program on seals and sea lions, which paid out CAN $14,329.50 over two years. That included the deaths of 2,875 sea lions in British Columbia in 1915 alone. Naturalists rebutted that sea lions mostly eat squid and were not a major threat to the region’s fish.
Walters believes that a 50 percent reduction would bring the seal population down to 1880 levels, when Indigenous peoples routinely harvested seals—though he concedes that details on such historical fisheries are sketchy.
Determining Indigenous peoples’ use of mammals in general is more problematic than sifting through shell middens, he says, because dogs often scattered the remains of harvested mammals.
Walters would prefer Indigenous people do the killing and earn an income from the sale of skins, oil, and meat. Any cull of Steller sea lions would first require removal of the animal’s rating as a species of special concern under the federal Species at Risk Act, he notes.
Walters believes scientists can be emotionally attached to their subjects. “People who go into marine mammal science tend to have a great love for the animals, and they tend to be opposed to harvesting and so on,” he says. “They’re looking for excuses to stop anything that would kill their beloved animals.”
When it comes to emotional responses, Walters is no exception. Asked what he would do about the several thousand male California sea lions that seasonally migrate north to British Columbia, he replied: “I’d kill every damn one that crosses the border, frankly. I’d like to see them treated as an exotic pest, which means you nail them every time you see them.”
Trites sees that age might make the difference in thinking on the subject.
“The generation I see for the most part supporting this kind of culling … harkens back to the 1970s and early 1980s, when we had a view of controlling nature for our economic benefit. Now, the younger generations are coming through and looking at the need for ecosystem considerations. It’s not about single species, it’s about valuing other aspects than how much fish can we catch and sell.”
Trites notes that harbor seal populations in British Columbia have been stable for 20 years, and that any massive cull would have serious consequences for threatened Bigg’s, or transient, killer whales that prey on seals and other marine mammals. On the other hand, if salmon populations do increase after a cull, it could benefit the endangered salmon-eating southern resident killer whales.
A just-completed report for Fisheries and Oceans Canada (DFO) synthesizes the results of two workshops meant to assess the effects seals and sea lions are having on salmon. The first workshop involved marine scientists from Canada and the United States, while the second also included Indigenous groups, the fishing industry, and nonprofit organizations.
“There’s a bit of a polarization between: we’ve got to do something now—a sense of desperation—and, well, this is some natural change going on and anything we do is probably not going to make the situation any better,” says the report’s author, Kurt Trzcinski, a zoologist at the University of Victoria in British Columbia.
“The underlying issue is perception of risk and what we should do—if anything,” Trzcinski says. “There’s a lot of uncertainty.”
The latest workshop asked participants how much risk they are willing to accept in pursuit of a massive cull. Those wary of a cull’s impact wanted as much as 80 to 100 percent assurance of a desired outcome, while those in favor supported as little as a 20 percent assurance of being right. Trites says the latter group includes those with a commercial stake in more fishing. “This is the most telling aspect. If there is a potential to make millions of dollars, then you go for it.”
Even if a phased cull is approved, Trites adds, it could take 10 to 20 years to determine how the salmon respond, during which time other factors could influence results. And what if a massive cull fails to make a difference? Trzcinski’s report cautions: “With the added complication of climate change, and changing environmental conditions there is no guarantee that pinniped populations would rebound.”
DFO’s position isn’t much different from the stance taken by naturalists more than 100 years ago. “While seals and sea lions do eat salmon, salmon represent a small proportion on average of their diet,” says Lara Sloan, a communications advisor for DFO. Sloan says DFO “does not employ broadscale seal and sea lion cull programs,” and that any proposals for a commercial harvest would require a lengthy review process taking years.
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October 22, 2020 at 02:14PM
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