Low-income countries that heavily depend on fish and seafood in their diets face escalating food security issues in the coming years due to climate change, with a potential 30% reduction in seafood nutrient sources, even greater in global hotspots, if temperature increases are not curtailed. This alarming revelation emerges from research published recently.
Countries with particularly concerning mariculture projections, including Nigeria, Sierra Leone, and the Solomon Islands, also anticipate substantial population growth and increasing demand for food security, despite diminishing seafood resources.
The United Nations Environment Program reports that approximately half of the world’s population already resides within 60 kilometers of the sea, and in these coastal regions, which include mega-cities like Beijing and Buenos Aires, coastal populations are projected to surge by more than 50% by 2050, in comparison to 2010 figures. Many of these nations have been prioritizing the “blue economy” for sustainable development.
Dr. William Cheung, the lead author of the study and head of the University of British Columbia’s Institute for the Oceans and Fisheries (IOF), stated, “Low-income countries and the global south, where seafood is central to diets and has the potential to help address malnutrition, are the hardest hit by the effects of climate change. For many, seafood is an irreplaceable and affordable source of nutrients.”
The research demonstrates an average loss of 4% to 7% of seafood nutrients for each Celsius degree of warming. In lower-income countries across the tropics, this loss is approaching 10% to 12% per degree. Cheung emphasizes that mitigating warming is synonymous with mitigating mariculture impacts, step by step.
The study, published in Nature Climate Change, suggests that if the Paris Agreement targets of limiting warming to 1.5°C to 2°C are achieved, the losses can be confined to roughly 10% of nutrient sources such as fish, shrimp, oysters, and other mariculture products. Regrettably, the world is not currently on this trajectory.
The research focuses on essential nutrients, including calcium, iron, protein, and omega-3 fatty acids. These nutrients not only hold significance as food sources in low-income countries but are also associated with heart health and reduced risk of type 2 diabetes worldwide.
The findings reveal that nutrient availability reached its peak in the 1990s and has plateaued through the 2010s, despite increased seafood farming and the harvest of more shrimp and oysters. Calcium, which was already insufficient for nearly half of the global population, faces the most substantial decline in the high-emissions scenario, potentially dropping by up to 40%.
Dr. Christina Hicks from the UK’s Lancaster University notes the significance of small pelagic (open sea) fish, stating, “In many parts of the world, particularly low-income countries across the tropics, fish supply nutrients that are lacking in people’s diets.”
Unfortunately, seafood farming cannot fully offset the losses from fisheries, especially in high emissions scenarios where any nutrient availability gains before 2050 would be negated by 2100.
Dr. Muhammed Oyinlola, a co-author and postdoctoral fellow at Canada’s Institut national de la recherche scientifique, points out, “The primary reason for this is climate change, which is also a significant threat to seafood farming, leaving us with a growing nutritional deficit. Seafood farming alone cannot provide a comprehensive solution to this complex issue.”
Potential adaptations could involve using nutrient-dense fish like anchovies and herring for human consumption instead of fish meal production, and minimizing food waste in production and supply chains.