Scientists are warning that exploitable fish biomass faces climate risks across nearly all regions of the world’s ocean, including top producer countries and those with a high reliance on aquatic foods, under a high-emissions scenario.
Global projections of the potential fish biomass production show declines of more than 10% by mid-century for many regions of the world, particularly under the high-emissions scenario, according to the report released this week by the Food and Agriculture Organisation of the United Nations (FAO).
The report was produced by the Fisheries and Marine Ecosystem Model Intercomparison Project (FishMIP), a program endorsed by the Ocean Decade and led by the University of Tasmania’s Institute for Marine and Antarctic Studies (IMAS).
“Under the high-emissions scenario, which projects global warming of 3–4.0°C, declines will worsen by the end of the century, to 30% or greater in 48 countries and territories,” said IMAS researcher, Professor Julia Blanchard, who leads the FishMIP program.
“However, under the low-emissions scenario, which projects global warming of 1.5–2°C, changes stabilise between no change and a decrease of 10% or less across 178 countries and territories, by the end of the century.
“Notable declines include those for top fish producer nations, which worsen towards the end of the century under the high-emissions scenario, for example 37.3% for Peru’s and 30.9% for China’s Exclusive Economic Zones,” Professor Blanchard said. “But this stabilises under the low-emissions scenario.
FishMIP is an international network of researchers working with FAO to understand the long-term impacts of climate change on marine ecosystems and fisheries through a set of state-of-the-art numerical models.
The report was released during the 36th session of the Committee on Fisheries (COFI36) held between 8 and 12 7月 2024 at FAO headquarters in Rome. The report comes on the heels of the latest edition of The State of World Fisheries and Aquaculture (SOFIA), which showed that world fisheries and aquaculture production hit a new high of 223.2 million tonnes in 2022.
Reducing hazards to marine ecosystems
“Understanding the potential impacts of climate change on marine ecosystems and their fisheries, and their associated uncertainties, is crucial to design adaptation programs at appropriate scales,” said FAO Assistant Director-General and Director of the Fisheries and Aquaculture Division, Professor Manuel Barange.
“Lower emissions significantly reduce end-of-century biomass losses for nearly all countries and territories compared to the high-emissions scenario. This highlights the benefits of climate change mitigation measures for fisheries and aquatic foods.”
A comparison of the losses projected under both scenarios by the end of the century reveals that lowering emissions has marked benefits for nearly all countries and territories.
This includes Small Island Developing States, where people rely heavily on fisheries for food and income and where the ecological and socioeconomic risks posed by climate change are highest. For example, among the Pacific Islands States, 68–90 percent of the extreme end-of-century losses projected under high emissions are averted by the low-emissions scenario for the Federated States of Micronesia, Nauru, Palau, Solomon Islands, and Tuvalu.
Achieving Blue Transformation
The report also highlights that, to assist countries in achieving FAO’s Blue Transformation vision of more resilient, equitable and sustainable aquatic food systems, future FishMIP research will need to encompass other ocean and coastal uses in addition to fisheries.
This would result in a more holistic view of managing marine natural resources in the face of climate change and inform trade-offs across sectors, including adaptive fisheries management and wider agrifood policies, aligned with priorities of the FAO Strategy on Climate Change and its Action Plan.
It would also help support policy directions at the nexus of climate change, biodiversity, water and food security, and health by addressing links with freshwater and terrestrial resource use, such as the reliance of aquaculture on both marine and terrestrial systems.
An international network of researchers
FishMIP was officially launched in 2013, with FishMIP2.0 established in 2024.
“Through this Ocean Decade Action program, we’ll be able to provide vital knowledge to industry and governments, to support effective planning for adaptive and resilient seafood sectors under climate change,” Professor Blanchard said.
“Our aim is to increase the reliability of modelling projections – and to answer a broader set of policy-related questions relevant to food security and marine resource management, with climate change as the overarching theme.”
Find out more about FishMIP here.
This article was originally published on the website of the University of Tasmania.