Fish populations have been declining for the past 80 years due to factors such as overfishing, pollution, and other anthropogenic activities. However, a recent study shows that ocean warming, an effect of climate change, also contributes to an overall population decline. Scientists examined data on ocean temperatures, catch sizes, fish populations, and fisheries between 1930 and 2010 and found that ocean warming caused a 4% global decline in sustainable catches. The greatest losses were observed along coastal regions in China and Japan, where fish populations decreased by up to 35%. The coastal area is a critical area for supporting the growing population’s demand for seafood, a staple of many Asian dishes; declining fish populations are an immediate cause for concern. If East Asian countries start importing fish to meet their fish demand, global prices will increase.
The study found that most fish populations declined, however, some other species benefited from warmer temperatures. Black sea bass populations in the Atlantic increased, but according to lead researcher, Christopher Free, if temperatures continue to rise, their productivity can fall, because “climate winners cannot be winners forever.”