Warming oceans are already chewing up the food chain:
Fish make up 17 percent of the global population’s intake of protein, and as much as 70 percent for people living in some coastal and island countries, according to the Food and Agriculture Organization of the United Nations.
As the oceans have warmed, some regions have been particularly hard-hit. In the northeast Atlantic Ocean and the Sea of Japan, fish populations declined by as much as 35 percent over the period of the study. “The ecosystems in East Asia have seen some of the largest decline in fisheries productivity,” Dr. Free said. “And that region is home to some of the largest growing human populations and populations that are highly dependent on seafood.”
And how soon will it be when national navies are deployed to escort fishing vessels so they can bring food home to the hungry masses? Vessels having their catch "confiscated" by cutters and frigates flying national (1st World) flags? That future is not as fictional as it sounds, if this trend continues:
A study published in January, also in Science, found that ocean temperatures were increasing far faster than previous estimates. Amid these changing conditions, fish are shifting where they live, in search of their preferred temperatures. High ocean temperatures can kill off both the fish themselves and the sources of food they depend on.
“Fish are like Goldilocks: They don’t like their water too hot or too cold,” said Malin L. Pinsky, an associate professor in the School of Environmental and Biological Sciences at Rutgers University and a co-author of the new study.
In about a quarter of the regions studied, fish had expanded their range. Off the Atlantic coast of the United States, sustainable catches of black sea bass increased by 6 percent over the study period. Another quarter of the regions saw no significant changes in fish populations, like the northwest Atlantic Ocean, where Atlantic herring are abundant.
But half the regions did not fare as well. The northeast Atlantic Ocean — home to Atlantic cod, the mainstay of fish and chips — saw a 34 percent decline in sustainable catches.
The researchers focused on sustainable catches, using a measure developed by the United Nations that quantifies the amount of food that can be repeatedly harvested from a base population of fish. “Fisheries are like a bank account, and we’re trying to live off the interest,” Dr. Pinsky said.
Several previous studies have predicted that climate change would lead to fewer ocean fish in the future, but the new research looked at historical data to determine that the declines had already begun.
Needless to say, these findings are not good. We're already facing a major challenge with land-based agriculture to produce enough food to feed the world's billions, and a major drop in seafood availability will make that much worse. We're talking destabilized governments with military capabilities (that we've sold them) taking aggressive steps to secure enough food to keep them in power, and it just goes downhill from there.
Have a nice weekend.