Shifts in the composition of marine fisheries catch are significantly related to temperature change in the ocean, according to an analysis in Nature this week. The study shows that warming has already affected global fisheries over the past four decades, by increasing the proportion of warmer-water fish species being caught. These findings provide a signature of the effect that climate change has on the distribution and abundance of marine organisms.
Understanding how climate change may affect marine fisheries is important as they contribute to the economy and are a key source of food to many coastal communities. William Cheung and colleagues analyse the changes in catch composition, in relation to the temperature preference of the species, in 52 large marine ecosystems from 1970 to 2006. They demonstrate that the distribution of stocks is shifting, with an increase in the number of warmer-water fish being caught globally, particularly in non-tropical areas.
The authors report that these results are independent of the effects of increased fishing efforts and other variations in the marine system. They also suggest that continued warming in the tropics could exceed the temperature preference of tropical fish, which may reduce the size of the catch in these regions. Taken together, these results highlight the need to develop adaptation plans immediately to minimize the impacts of climate change on the economy and food security of coastal communities.