Fisheries targeting tuna face the highest risk from climate change, according to new research. A global study of more than 500 certified fisheries found that stocks of highly migratory species, such as tuna and billfish, are shifting rapidly as ocean temperatures rise.
This could lead to more disputes between coastal states and an increased risk of overfishing if management systems fail to adapt.
Tuna stocks on the move
The research was led by the Marine Stewardship Council (MSC) and will be published in Cell Reports Sustainability. It shows that tuna are already changing their migration routes to seek cooler waters.
In the Pacific, stocks are shifting east. In the Atlantic, bluefin tuna have reappeared around the UK after being absent for decades.
These changes mean tuna may move across borders faster than current management agreements can respond. If governments cannot agree on new quota-sharing systems, the risk of unsustainable catches increases.
Small pelagics are also exposed
The study found that small pelagic fisheries, such as those for mackerel, herring, and blue whiting, face the next highest level of climate risk. Like tuna, these species move quickly when temperatures change. Whitefish, including cod, haddock and plaice, are also vulnerable.
In contrast, fisheries for sedentary invertebrates — such as crabs, prawns and bivalves — are less exposed to geopolitical risks because the species do not migrate. However, the researchers note that these fisheries may still be affected by ocean acidification and marine heatwaves.
Call for stronger cooperation
The MSC states that countries must adopt flexible quota systems that can adjust as stocks fluctuate. It also warns that countries unable to meet sustainability standards will be even more exposed.
“Climate change shows no signs of slowing,” the report states. “Governments need to adapt their practices to keep pace.”