Climate Change and the IPCC report: Fish in hot water
The latest Intergovernmental Panel on Climate Change (IPCC) report has very grim news for the world and for Seychelles. Nature Seychelles will cover aspects of the report relevant to Seychelles. Today, we look at fish.
The ecosystems that support the stability and growth of the fisheries are failing
The world’s already overtaxed fisheries are being stressed to their limits by climate change, putting at risk a critical component of the world’s diet. As temperatures rise, fish populations are projected to plummet and disappear in some regions, especially in the tropics." IPCC, 2021
Seychelles’ fisheries are in hot water, literally. Popular species of both the artisanal fishery, which feeds the people and the industrial tuna fishery, which supplies the world’s largest tuna cannery and supplies over 90% of Seychelles’ exports, are overfished or being overfished. The infamous case of Yellowfin tuna in the Western Indian Ocean, where it is the most overfished tuna stock in the world, is well known. Catch has to be reduced by 30% for recovery to take place by 2030. But the new estimate of the status of these tuna populations shows that the other tuna species are also being overfished. And on top of all that, climate change is affecting the fisheries. Warmer sea surface temperature means that tuna prey may not come to the surface where tuna can catch them easily. A study found that in 2018 when there was strong warming of the waters of the Western Indian Ocean, the direct and indirect economic benefits of the tuna industry declined by 58% and 34% respectively.
It is known from various studies that fish in tropical oceans are already living in water that is approaching the upper temperature limits of what they can tolerate. They will not be able to adapt when temperatures increase even slightly. In these cases, fish will either migrate somewhere else, adapt, or die off as temperatures continue to warm. This may very well be the case for tuna.
Seychelles is what is termed as a fish dependant country
For coastal fish species loved by Seychellois such as parrotfish, snappers, groupers, and emperors, habitat loss is a big problem. Corals have declined by almost 90% in general in the granitic islands because of the impacts of climate change. The ecosystems that support the stability and growth of the fisheries are therefore failing. According to the Fisheries at Risk Report 2020, Seychelles fisheries have the highest increase in exposure to climate change impacts in the world. The latest research shows that Marine Heat Waves (MHWs) in the Indian Ocean are increasing and are the worst in the western part where Seychelles is located. A study in December 2021 said coral reefs in the Western Indian Ocean could die in 50 years because of climate change.
Seychelles is what is termed as a fish-dependant country. We depend on fish caught in our waters for both food and nutrition security as well as for livelihoods. While we can move away from fish, the consequences of shifting from fishing would not only impact our diet, it would also alter our cultural, recreational, and economic activities linked to fishing.
Climate change impacts on fisheries cannot be overstated. Fisheries are not only the second pillar of the economy but are also vital for the social stability of Seychelles. We need to be far more aware of the impacts of climate change on this pillar of sustainability.