Warming Oceans and Waterways Threaten a Key Human Protein Source

Fish are shrinking and dying at higher rates as they adapt to warming oceans, according to a report released Thursday in the journal Science by researchers including Craig White of Monash University. The evolutionary shift will reduce global fish yields by one-fifth under current warming predictions, with Alaska pollock alone losing half a million metric tons harvested annually—equivalent to 1.1 billion meals of high-quality protein per year. Smaller fish become vulnerable to predation and can trigger ecosystem collapse, as happened on Canada's western Scotian shelf where top predator average size dropped 40 percent in four decades. Researchers warn that without effective climate policy to reduce warming, populations may become locked into new food chain states they cannot reverse, threatening the billions of people who depend on seafood for protein.