New research shows that aquaculture now accounts for half of the fish consumed globally, but the production system relies largely on feed made from wild fish harvested from the sea.

The study, reported in the Proceedings of the National Academy of Sciences, finds that inclusion rates of fishmeal and fish oil from wild sources in feeds has declined, but overall use is up due to increased aquaculture production and demand for fish high in long-chain omega-3 oils, such as salmon. The report notes that various plant- and animal-based alternatives are now used or available for industrial aquafeeds, depending on relative prices and consumer acceptance, and the outlook for single-cell organisms to replace fish oil is promising. With appropriate economic and regulatory incentives, the transition toward alternative feedstuffs could accelerate, paving the way for a consensus that aquaculture is aiding the ocean, not depleting it.

View a research abstract.