
An example of an aquaculture farm in open water, used from the greenlifesaver.wordpress.com blog.
This week, I’ve been busy researching aquaculture for an article I’m writing. I visited a school that has an aquaculture facility and saw some of the new technology for recirculating systems – each one contains a large tank to grow fish, and other equipment to eliminate waste in the water – at the Center of Marine Biotechnology. These two sites grow fish for educational purposes only.
But it got me thinking about aquaculture for consumption. About half of the seafood we consume comes from aquaculture farms, according to the Monterey Bay Aquarium. While fish farming seems like a great way to solve the problem of our dwindling seafood supply, many farming practices are harmful to the environment.
Here are three of the biggest issues in aquaculture production for consumption:
- Water Pollution and Disease: If fish are farmed in open net pens or cages in oceans or lakes, for example, byproducts like fish waste and antibiotics used on the fish are released into the environment. The fish waste adds extra nutrients to the ecosystem, according to the Ocean Conservancy, which can harm biodiversity. Antibiotics and chemicals can affect wild fish.
- Escaped Fish: Millions of fish escape from aquaculture operations every year. When this happens, the farmed fish compete with wild fish for food and, in the worse cases, breed with native fish, “changing forever the gene pool of the native species,” according to the Monterey Bay Aquarium.
- Wild Fish: Many fish are carnivores, eating diets comprised of other fish. “On average it takes over three pounds of wild fish to grow a pound of farmed salmon,” writes the Monterey Bay Aquarium.
Reading all this overwhelms me: before eating fish, should we ask if it’s wild and, if so, a significantly depleted species? Or if it’s farmed, should we find out what type of farming method was used? Either way, we could also ask where the fish comes from: in 2008, imports made up 83% of the seafood consumed in the U.S., according to the National Oceanic and Atmospheric Administration.
There are some resources that can help. The Monterey Bay Aquarium publishes Seafood Watch, a list of the best, most sustainable choices we can make when eating fish. You could try using this guide as a starting point, but Mark Bittman, who writes The Minimalist column for The New York Times, says it’s difficult to follow.
You can eat the few remaining fish species that are not troubled, which are sardines, mackerel, and squid, according to Bittman.
Or you can read Bittman’s article to learn more about the fish industry and the rules he follows when consuming fish, and make your decisions from there. If you’re interested in aquaculture issues, the Monterey Bay Aquarium and the Ocean Conservancy offer helpful information.
Also, it should be noted that not all farmed fish are bad. It seems to depend on how they are farmed. Which further complicates things. To me, sustainable, healthy, and environmentally-friendly fish consumption is the most confusing issue in conscious eating.
If you have any ideas/thoughts about aquaculture and seafood sustainability, please tell us about them.






[...] It is also “aquacultured around the world from Asia, to South America, to the United States and Canada,” according to the Food Lover’s Companion. The fish we ate was indeed farmed. But the Monterey Bay Aquarium says that tilapia is a good choice for farming, and that the tilapia farmed in the U.S. are the best choice. Tilapia from China and Taiwan should be avoided, “where pollution and weak management are a problem.” (Read my thoughts on aquaculture in the post “Aquaculture and Seafood: the Good, the Bad, and the Sustainable.”) [...]