Anthropocene Magazine
“First, the major source of emissions in aquaculture is the production of feed for the farmed fish. In fact this accounted for a striking 70% of emissions for most farmed fish, most notably flatfish and crustaceans, the researchers found. The footprint is attributable to the land conversion and fertilizers that are needed to produce the feed, which are typically soybeans. This land-based food production also gives farmed fish a relatively high footprint where water use is concerned.
In wild-caught fisheries meanwhile, the primary emissions culprit is fuel-use for boats, especially true for high-seas industrial fleets that may travel long distances to capture fish.
This assessment also revealed which are the ‘greenest’ blue foods to consume. The researchers found that across all fish – farmed and wild-caught—the lowest-impact were farmed bivalves and seaweeds, mainly because they don’t need to be fed. In fact, their self-sufficiency gives them an ecosystem benefit, because shellfish and seaweed can remove nitrogen and phosphorus pollution—usually originating from terrestrial agriculture—from the water. What’s more, bivalves especially have some of the highest nutritional value of all available blue foods, presenting a clear win on all fronts.”
