Aquaculture should not be evaluated in isolation from other food production systems. With a human population expected to reach nearly 10 billion by 2050, science needs to consider the real measures and trade-offs that exist around what we consume and how we produce and capture food - particularly regarding animal protein. Food production will always impact the planet at some level. The key is assessing how different decisions and actions at both the ecosystem and farm scale impact people and nature.
Most fed aquaculture species (finfish and crustacea) rely on wild-captured forage fish (e.g., herring, sardines) for essential fatty acids and micronutrients, an important but limited resource. As the fastest growing food sector in the world, fed aquaculture demand will eventually surpass ecological supply of forage fish, but when and how best to avoid this ecological boundary is unclear. Using global production data, feed use trends, and human consumption patterns we show how combined actions of fisheries reform, reduced feed use by non-carnivorous aquaculture and agricultural species, and greater consistent inclusion of fish byproducts in China-based production can circumvent forage fish limits by mid-century. However, we also demonstrate the efficacy of such actions are diminished if global diets shift to more seafood (i.e., pescetarian diets) and are further constrained by possible ecosystem-based fisheries regulations in the future. Long-term, nutrient-equivalent alternative feed sources are essential for more rapid and certain aquaculture sustainability. See the publication in Nature Sustainability for more details.
We simulated how different forms of aquaculture contribute and compare to feed and land use of terrestrial meat production and how spatial patterns might change by mid-century if diets move towards more cultured seafood and less meat. Using country-level aquatic and terrestrial data, we show that aquaculture requires less feed crops and land, even if over a third of protein production comes from aquaculture by 2050. However, feed and land sparing benefits are spatially heterogeneous, driven by differing patterns of production, trade, and feed composition. Ultimately, our study highlights the future potential and uncertainties of considering aquaculture in the portfolio of sustainability solutions around one of the largest anthropogenic impacts on the planet. See the paper in PNAS for details
New Research (starting 2018)
Mapping the location and extent of current environmental impacts of food production systems.