Leveraging biodiversity to maximize nutrition and resilience of global fisheries

Abstract

Wild fish harvests from freshwaters and oceans per person on Earth have been stagnating for decades due to increased food demand from a burgeoning global human population, raising the stakes for maximizing the nutritional benefits from limited fish stocks. Here we adopt an allocation optimization approach using biogeographic and nutrient data for the world’s fishes to identify ideal portfolios of species for consumption in every country. We find that, across nations, biodiversity increases opportunities to fulfil multiple nutritional requirements with less fish biomass. This advantage emerges through complementarity among species; portfolios of complementary species provide >60% more nutrients than the same biomass of the most nutrient-rich species. Moreover, biodiverse fisheries enable harvest allocation towards species with traits enhancing fishery resilience (for example, small size, low trophic position) and offer greater redundancy, whereby a wider range of comparably nutritious species is available. Our analysis underscores that conserving fish biodiversity can improve nutrition and fishery resilience while reducing harvest pressure on already-stressed aquatic ecosystems. Marine and freshwater fisheries around the world have had stagnating stocks due to increased demands in food from a growing human population. Authors here assess how biodiversity levels of fisheries around the world can be leveraged to maximize nutrients provided with less biomass.