Our global analysis shows that small-scale fisheries are an important source of key nutrients for vulnerable coastal populations. We estimated that about one quarter of coastal nations around the world rely on small-scale fisheries for more than 15% of mean nutrient intake across assessed nutrients (iron, zinc, calcium, DHA + EPA and vitamins A and B12). Several nutritionally vulnerable countries (defined as a mean national prevalence of inadequate intake over 50%), mainly in Africa, Pacific, Caribbean, and Asia, obtain more than 30% of their nutrient supply from small-scale fisheries catch. In such countries, any decline in catch can have significant negative consequences on the health and nutrition of the population.
Small-scale fisheries catch is particularly important in populations that do not have access to diverse and rich diets. In many coastal areas around the globe, communities have access to staple foods (such as rice, wheat, corn, cassava) and aquatic foods serve as the sole form of animal-sourced food19. For example, a study in Bangladesh showed that fish intake corresponded to about 40% of the recommended Vitamin A consumption and 32% of the calcium consumption20. And, household surveys in the Pacific islands demonstrated high frequency of SSF consumption by coastal communities in Tuvalu and Kiribati (5.6 and 6.1 times per week, respectively)21,22. In these types of diets, nutrients from SSF, such as DHA + EPA fatty acids and vitamin B12, are especially important for public health. Importantly, intake of DHA + EPA is associated with reduced risk of heart disease8, and intake of vitamin B12 is associated with reduced risk of heart disease and cognitive decline23. Here, we show that small-scale fisheries have particularly high contribution to the supply of vitamin B12, calcium and DHA + EPA, although it can also be important for other nutrients depending on the nutritional value of the species consumed and availability of other foods.
There are many reasons to believe our findings are a conservative estimate of the contribution of small-scale fisheries to human nutrition. First, we assumed that coastal populations have the same national average intake of other food types (including other animal-sourced foods) based on the GND database. However, in coastal communities, fish can often be the only source of animal-sourced foods, and other food types are not accessible. Second, to calculate per capita consumption, we assumed that the entire coastal population within each country is consuming the small-scale fisheries catch. However, a large proportion of the catch can be sold in local markets around fishing communities. Many people living in larger cities along the coast might not consume small-scale fisheries catch and coastal communities might have higher than average seafood consumption. Therefore, average values presented here does not capture temporal and spatial variability in small-scale fisheries catch consumption across coastal populations. Third, even though the Sea Around Us database accounts for unreported catch, a portion of the small-scale fisheries production could still be unreported 16. Lastly, we conservatively considered that artisanal catch is part of the international seafood trade. However, in many countries the artisanal catch is destined to the local markets, with only very few highly valuable species being exported24. Better data on these topics will increase the accuracy of the results presented here.
It is critical to understand whether SSF fisheries production is stable over time or potentially declining due to overfishing, climate change, pollution, or other threats that could have negative impacts on human nutrition. Nutritionally vulnerable coastal populations that depend on SSF and are particularly susceptible to fluctuations in catch and can benefit from sustained or increased catch through better resource management. Successful examples of small-scale fisheries governance suggest the value of securing fishing rights and empowering local communities 25–27. Strategies that grant fishing rights to local communities (such as sustainable-use Marine Protected Areas, Territorial Use Rights for Fisheries, Locally Managed Marine Areas) incentivize management and promote sustainable practices28–31, and thus can promote human health through nutrition. The Voluntary Guidelines for Securing Sustainable Small-scale Fisheries developed by the Food and Agriculture Organization of the United Nations 9 recognizes the importance of securing tenure rights to achieve fisheries sustainability. Such principles are drawn from practical experiences of small-scale fisheries governance from around the world and can be adopted by nutritionally sensitive countries that depend on small-scale fisheries for nutrition.
In addition to improved management, policies supporting access to nutrient-rich fish could have a positive impact on diets where undernutrition is prevalent. Aquatic foods are one of the most widely traded food products in the world, moving nutritious food away from countries experiencing high prevalence of inadequate intake32. Although most SSF catch is consumed locally15, policies prioritizing local consumption and targeted to specific nutritional needs can help address inadequate nutrient intake and improve food security. Other policies that reduce food waste, improve food quality and safety, and help cope with inter-annual variation or declines can also play an important role in improving human health in regions where nutrients are most needed. This is particularly true in countries with nutritionally vulnerable populations who have high dependence on small-scale fisheries.