Opponents of open-net-cage salmon farming maintain that the aquaculture practice is bad for wild stocks. With an estimated 34 million Fraser River sockeye coming back this summer, in what’s described as the biggest return in a century, does this mean they’ve got it wrong?
Not at all, says Catherine Stewart, a Vancouver-based campaigner with Living Oceans Society.
Her group believes that fish farms located in the waters between eastern Vancouver Island and the mainland are incubators of sea lice and diseases that waylay wild-salmon juveniles migrating out to sea through the Johnstone Strait.
“This year has nothing to do with last year,” Stewart asserted in a phone interview with the Georgia Straight. “What we need to know from the aquaculture industry is what were the conditions of the farms in the strait when the 2009 fish migrated out to sea?”
Young sockeye live their first two years in freshwater rivers and lakes, later swimming out to the ocean, where they spend another two years before returning to their natal streams to spawn.
This means the fish that came back to the Fraser in 2009 made their way out to sea in 2007, while the sockeye surging back to the river this summer made their passage in 2008.
“You can imagine that in one year if the lice levels were extraordinarily high, it could be harming their own farmed fish, and so they might have brought that situation under better control, and the following year—when the 2010 class of Fraser sockeye migrated past the farms—they had a better handle on the lice situation,” Stewart said. “But because the industry is so secretive and because they won’t release data and fight tooth and nail against release of data on what was actually going on in the farms, we don’t know.”
Stewart also said that conservationists hope the ongoing federal inquiry into the 2009 collapse of the Fraser sockeye will lead to the disclosure of more information about fish farms.
Salmon farming started in B.C. in 1971, and according to the most recent joint report by the ministries of agriculture and lands and environment, it had grown to a $406-million industry by 2008. During that same year, the initial estimate for the farmed-salmon harvest was 81,400 tonnes.
Marine Harvest Canada, a Norwegian subsidiary, is the biggest salmon-farming company in the province. According to spokesperson Ian Roberts, the Vancouver Island firm operates 35 farms and accounts for half of the total production of mesh-net-grown salmon.
In a phone interview from Campbell River, Roberts pointed out that it isn’t just sockeye that are making a strong return. He said that chinook, coho, and pink salmon have also done very well this year.
“We disagreed back then that we were to blame for any low numbers of wild salmon, but we were very polite about it,” Roberts told the Straight. “We took the criticism. It was upsetting to be accused of something that you knew you weren’t responsible for. But we took it on the chin, knowing that salmon are cyclical and the salmon will return. And they have.”
Carl Walters, a professor at the UBC Fisheries Centre, describes himself as a fish-population expert who has studied sockeye and pink salmon for 40 years.
“My personal opinion is that the claims about fish-farming effects on either of those species are bogus,” Walters told the Straight by phone. “It is certainly not a matter of fact that fish farming has affected those populations. It is quite unlikely that fish farming has anything to do with the changes in sockeye-salmon numbers that we’ve seen, the downs or ups.”
Like Living Oceans Society, the Coquitlam-based Watershed Watch Salmon Society considers net-cage aquaculture of salmon a threat to the wild species. Its resident fish biologist, Stan Proboszcz, explained by phone that although there are other factors involved in the changing numbers of spawning salmon, “it’s pretty tough to eliminate farms.”
In April 2009, a group of scientists from Canada, Norway, and Scotland released a report on sea lice.
Commissioned by the Salmon Aquaculture Dialogue, an international forum initiated by the World Wildlife Fund in 2004 that includes salmon producers, the paper noted that “evidence is largely indirect or circumstantial that sea lice emanating from salmon farms can and do exert detrimental effects on wild salmonids.”
However, the report also stated that the “weight of evidence is that sea lice of farm origin can present, in some locations and for some host species populations, a significant threat”.