One more effect of climate change and warming oceans: New research in Nature Climate Change finds that the maximum body of weight of ocean fish could decline by 14-24% by 2050, under high greenhouse gas emissions scenarios. In tropical and intermediate latitudes the average reduction could be over 20%.
This conclusion is based off computer modeling of more than 600 species of fish around the world, applying the idea that fish growth is limited by oxygen supply in the water.
Study co-author Daniel Pauly:
It's a constant challenge for fish to get enough oxygen from water to grow, and the situation gets worse as fish get bigger. A warmer and less-oxygenated ocean, as predicted under climate change, would make it more difficult for bigger fish to get enough oxygen, which means they will stop growing sooner.
The study found that roughly half of the decline in maximum weight was due to physiological factors, with the other half being due to changes in distribution and abundance of the species studied.