March 25, 2021 — Twenty years ago, as farmed salmon and shrimp started spreading in supermarket freezers, came an influential scientific paper that warned of an environmental mess: Fish farms were gobbling up wild fish stocks, spreading disease and causing marine pollution.
This week, some of the same scientists who published that report issued a new paper concluding that fish farming, in many parts of the world, at least, is a whole lot better. The most significant improvement, they said, was that farmed fish were not being fed as much wild fish. They were being fed more plants, like soy.
In short, the paper found, farmed fish like salmon and trout had become mostly vegetarians.
Synthesizing hundreds of research papers carried out over the last 20 years across the global aquaculture industry, the latest study was published on Wednesday in the journal Nature.