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.
Injustices are prevalent in food systems, where the accumulation of vast wealth is possible for a few, yet one in ten people remain hungry. Here, for 194 countries we combine aquatic food production, distribution and consumption data with corresponding national policy documents and, drawing on theories of social justice, explore whether barriers to participation explain unequal distributions of benefits. Using Bayesian models, we find economic and political barriers are associated with lower wealth-based benefits; countries produce and consume less when wealth, formal education and voice and accountability are lacking. In contrast, social barriers are associated with lower welfare-based benefits; aquatic foods are less affordable where gender inequality is greater. Our analyses of policy documents reveal a frequent failure to address political and gender-based barriers. However, policies linked to more just food system outcomes centre principles of human rights, specify inclusive decision-making processes and identify and challenge drivers of injustice.
Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages-the foundation species of coral reef ecosystems. Here, we compiled coral abundance data from 2,584 Indo-Pacific reefs to evaluate the influence of 21 climate, social and environmental drivers on the ecology of reef coral assemblages. Higher abundances of framework-building corals were typically associated with: weaker thermal disturbances and longer intervals for potential recovery; slower human population growth; reduced access by human settlements and markets; and less nearby agriculture. We therefore propose a framework of three management strategies (protect, recover or transform) by considering: (1) if reefs were above or below a proposed threshold of >10% cover of the coral taxa important for structural complexity and carbonate production; and (2) reef exposure to severe thermal stress during the 2014-2017 global coral bleaching event. Our findings can guide urgent management efforts for coral reefs, by identifying key threats across multiple scales and strategic policy priorities that might sustain a network of functioning reefs in the Indo-Pacific to avoid ecosystem collapse.