Global Fisheries and Climate Change
A story by Tom Zeller at Huffington Post this week highlighted the intersection between climate change and global fisheries. I blogged a couple of weeks ago about the potential impact of climate change on agriculture and livestock production as the world crossed the 400 ppm CO2 barrier. Zeller explores a similar question in the context of fisheries.
The central challenge stems from the fact that the world’s oceans are getting warmer. As a result fish stocks, which had already been under stress from dramatic expansion in fishing (see graphic below) are increasingly under risk of collapse. But, as Zeller points out, scientists are still struggling to get a handle on the exact impact of climate change, which a national conference on fisheries management called “the single greatest challenge facing fisheries managers.” As John Shepherd put it, “Managing fisheries is hard: it’s like managing a forest, in which the trees are invisible and keep moving around.”
There are real economic and social implications associate with these changes. In the United States alone, national commercial fisheries generate some $116 billion in annual sales and employ more than 1 million people. And for poor coastal communities around the world, fish comprise the single most important source of protein. Advances in fishing technology—GPS, sonar, trawling nets, and so on—have enabled commercial fishing vessels to cover greater and greater portions of the world’s oceans, feeding growing global demand for fresh seafood. And as they have done so, an increasing number of fisheries have begun to collapse. Atlantic cod fisheries have already collapsed, and Peruvian anchovies, Bluefin tuna, and Irish sole are all at risk. A 2006 study predicted that by 2048, all current fish and seafood species could collapse.
Climate change, in other words, might just be the proverbial straw that breaks the camel’s back.