Wild-caught fish provide an irreplaceable source of essential nutrients in food-insecure places. Fishers catch thousands of species, yet the diversity of aquatic foods is often categorized homogeneously as 'fish', obscuring an understanding of which species supply affordable, nutritious and abundant food. Here, we use catch, economic and nutrient data on 2,348 species to identify the most affordable and nutritious fish in 39 low- and middle-income countries. We find that a 100 g portion of fish cost between 10 and 30% of the cheapest daily diet, with small pelagic fish (herring, sardine, anchovy) being the cheapest nutritious fish in 72% of countries. In sub-Saharan Africa, where nutrient deficiencies are rising, <20% of small pelagic catch would meet recommended dietary fish intakes for all children (6 months to 4 years old) living near to water bodies. Nutrition-sensitive policies that ensure local supplies and promote consumption of wild-caught fish could help address nutrient deficiencies in vulnerable populations.
Sustainable development aspires to "leave no one behind"1. Even so, limited attention has been paid to small-scale fisheries (SSF) and their importance in eradicating poverty, hunger and malnutrition. Through a collaborative and multidimensional data-driven approach, we have estimated that SSF provide at least 40% (37.3 million tonnes) of global fisheries catches and 2.3 billion people with, on average, 20% of their dietary intake across six key micronutrients essential for human health. Globally, the livelihood of 1 in every 12 people, nearly half of them women, depends at least partly on small-scale fishing, in total generating 44% (US$77.2 billion) of the economic value of all fisheries landed. Regionally, Asian SSF provide fish, support livelihoods and supply nutrition to the largest number of people. Relative to the total capture of the fisheries sector (comprising large-scale and small-scale fisheries), across all regions, African SSF supply the most catch and nutrition, and SSF in Oceania improve the most livelihoods. Maintaining and increasing these multidimensional SSF contributions to sustainable development requires targeted and effective actions, especially increasing the engagement of fisherfolk in shared management and governance. Without management and governance focused on the multidimensional contributions of SSF, the marginalization of millions of fishers and fishworkers will worsen.