NPR’s Living on Earth broadcasted a fascinating segment yesterday on new fish farming techniques that could solve the health and environmental problems associated with farmed salmon.
You’ve likely heard that farmed salmon have higher concentrations of toxins like PCBs than wild salmon. A new study published in The Environmental Health Perspectives journal showed that contaminants like those found in farmed fish are linked to insulin resistance—a precursor to diabetes.
These persistent organic pollutants are everywhere in the environment, but end up concentrated in carnivorous fish like farmed salmon because these farmed salmon are fed a strict diet of only wild-fish-infused pellets.The pellets are concentrated with toxins, which then further concentrates the salmon with toxins. The farmed salmon are what they eat. (Apparently wild salmon have a much more diverse diet.)
Another problem with farmed salmon: poop. If farmed fish are in an open bay, the excrement (and other baddies like chemical treatments and antibiotics) escape into the wild.
Despite recommendations to avoid farmed salmon, farmed fish is the world’s fastest-growing animal food production system and recently surpassed wild catch as the majority of the world’s fish consumption, according to Environmental Health Perspectives.
The good news: The Monterey Bay Aquarium recently gave its thumbs up to a different way of fish farming.
“So, rather than positioning the farm out in a bay where all of those products just flow out into the wild, we started seeing some of these farmers moving these farms onshore, putting them into tanks where they're containing the fish, containing the fish waste; all of those detrimental impacts are now being managed by the farm, so it's not creating these kind of areas of impact within the wild environment,” said Sheila Bowman of the Monterey Bay Aquarium to Living on Earth host Jeff Young.
The fish also eat a more mixed diet, including chicken. Yes, you heard right.
Is it healthy progress to feed fish chicken? Time will tell. Bowman said that fish raised in these new types of farms won’t be available in the mass marketplace for a few years. I’ll be on the lookout. In the meantime, Bowman recommends that most people avoid farmed salmon.