Possibly thousands of fish from Marine Harvest, the world’s largest producer of farmed salmon, escaped from their 127,000-fish cage over the weekend through a hole created by inclement weather and strong winds. Quite aware of the havoc the mass release of so many farmed salmon could cause on the environment, the company is offering a bounty of $90 per returned fish, each of which weighs about 40 pounds.
“We acknowledge that escapes can have a negative impact on wild salmon, and we have a goal of zero escapes,” as Marte Grindaker, a spokeswoman for Marine Harvest, told Al Jazeera.
“Negative impact” is a bit of an understatement. Farmed salmon are often bigger, and therefore faster, than fish in the wild. They are fed quantities of compounds such as astaxanthin and canthaxanthin – carotenoids that give them their pink color — that wild fish obtain naturally. Farmed fish will likely compete with endangered wild salmon for food and can pass on sea lice and viruses as well as contaminants, parasites and pathogens, according to the Environmental Defense Fund. Should the farmed and wild salmon breed with each other, genetically inferior offspring will likely result.
Escapes of Fish From Farms Not Uncommon
Grindaker cites the “quite harsh” weather conditions as a reason that Marine Harvest has yet to figure out how many farmed salmon escapees there are. Such escapes of large numbers of farmed fish are actually not uncommon. The Norwegian Fisheries Directorate says that, in 2006, 921,000 fish escaped from fish farms. The huge underwater cages where they are raised can be breached by strong winds and predators such as seals.
As Martin Krkosek, a biologist at the University of Toronto who studies aquaculture, recently noted, “the rate of escapees has declined dramatically.” In 2012, 38,000 of Marine Harvest’s farmed fish escaped though, just in October, the company, lost some 20,000 salmon to a jellyfish invasion of its farms off the Irish coast.
Safety of Farmed Fish for Human Consumption Still Debatable
The escape of so many farmed salmon casts yet another shadow on the aquaculture industry. A controversial 2004 study found that farm-raised fish contain higher rates of carcinogenic chemicals including PCBs and other toxic contaminants. These have been banned in most salmon-producing countries but are still in the environment and, in some cases, even the feed for farmed salmon.
The World Wildlife Fund, which established the Aquaculture Stewardship Council (ASC) to create sustainability standards for fish aquaculture worldwide, and others say that, due to advances in aquaculture techniques, farmed salmon are now acceptable and even preferable to their wild counterparts. Some farmed salmon, like Verlasso from Chile, are now listed as acceptable as, should these escape, they are not at risk of breeding with wild salmon who are native to the northern hemisphere. But Marine Harvest’s are listed as a type to “avoid” on the Monterey Bay Aquarium’s Seafood Watch Advisory.
In Europe and the United States, the consumption of farmed salmon now far exceeds that of wild salmon. This is not surprising considering that, while two billion pounds wild salmon are harvested per year, five billion pounds are now produced on fish farms. Wild salmon have become so rare that, says Al-Jazeera, “divided among the world’s population, … could provide only a single serving for each person per year.” But is it worth it to eat farmed fish?
Marine Harvest says that it has set out nets near the fish cage in an attempt to recapture the salmon. As of November 18, none have been returned and, as Grindaker says, it is unknown how many have escaped. Along with health concerns about farmed salmon, this latest escape of so many fish from farms leaves plenty of reason to question the safety and viability of the aquaculture industry, both for humans’ health and for that of marine ecosystems.
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