Can Salmon Farming Be Sustainable? Maybe, If You Head Inland
Is salmon farming ever sustainable?
For years, the answer to that question has been clear for marine biologists, many of whom agree that the floating, open-ocean net pens that produce billions of pounds of artificially colored salmon per year also generate inevitable pollution, disease and parasites. In some places in western Canada, the open-ocean salmon farming industry has even been named as the culprit in the collapse of wild salmon populations.
But now, a few salmon farms have moved inland, producing fish in land-locked cement basins separated from river and sea. One land-based fish farm in West Virginia has been commended as a sustainable alternative to conventionally produced salmon. On Vancouver Island, there is at least one such facility. And just last month, Willowfield Enterprises, based in Langley, British Columbia, harvested its first inland-farmed sockeye salmon, to be marketed under the brand name West Creek. Sockeye is a Pacific species that has rarely been cultivated before.
"In terms of environmental sustainability, I think [these closed-system farms are] a huge step forward," says Martin Krkosek, an assistant professor at the University of Toronto who has been among the leading critics of ocean net pen salmon production. "Waste material, disease, pollution, parasites — all these things aren't a concern with most closed-system aquaculture."
Some forms of aquaculture may have the potential to help ecosystems by taking fishing pressure off of wild fish stocks. But this hasn't been the case with the salmon farming industry, according to notable experts like Daniel Pauly, a professor of fisheries at the University of British Columbia. One reason why, Pauly tells The Salt, is that the food that salmon farmers feed to their fish is usually fish meal made from wild — sometimes overfished — species. He points out that humans could be eating these species instead of farmed salmon.
Open-ocean salmon farms also generate high densities of organic and inorganic waste material — essentially, untreated raw sewage that can cause toxic marine algae blooms and create low-oxygen "dead zones." Residues from antibiotics and other chemical treatments can also drift from the pens.
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