According to NRDC, the long-term economic impacts of ocean acidification are expected to be most severe in regions where waters are acidifying soonest (black) and where the residents rely most on local shellfish for their livelihood (red). Local factors such as agricultural pollution (green), naturally-occurring upwelling currents (purple) and poorly buffered rivers (blue) can amplify acidification locally. Graphic: Natural Resources Defense Council

By Maria Gallucci
23 February 2015 (IBT) – Taylor Shellfish Company was grappling with a crisis in the summer of 2009. Millions of oyster larvae were dying in its Washington hatcheries, and production had dropped by 80 percent. Down the coast, Oregon’s hatcheries faced the same problem. Highly acidic ocean water, it turned out, was dissolving the microscopic oysters. Part of the acid blast came from naturally occurring events. But human-caused “ocean acidification” — which occurs when oceans absorb carbon dioxide emissions — was also partly to blame, the company later learned. “There’s no question that [man-made] CO2 contributed to oyster mortality,” Bill Dewey, public affairs manager for Taylor Shellfish in Shelton, Washington, said. The company has since installed high-tech monitoring and water treatment systems in its hatcheries, and oyster larvae have mostly recovered. But seedlings, the next stage in oyster life, are struggling to grow, and the company suspects acidic water could be the culprit, Dewey said. “We’re the canary in the coal mine for what’s happening with our shellfish industry,” he said. “Conditions are going to get progressively worse.” Ocean acidification isn’t limited to Washington’s waters. The phenomenon is striking more than a dozen other “bioregions” along the U.S. coastline, threatening to disrupt local shellfish industries from southern Massachusetts and Virginia to swampy Louisiana and southern Alaska, according to a new study by the Natural Resources Defense Council. The economic implications could be vast. In the Pacific Northwest alone, acidification already cost the oyster industry an estimated $110 million and jeopardized thousands of jobs, according to a Washington state science panel. Oceans have so far absorbed about one-fourth to one-third of all man-made carbon emissions, scientists estimate. As the U.S. and other countries burn more oil, coal and natural gas for energy, the ocean could become an increasingly hostile home for marine life. The NRDC report, published Monday in the journal Nature Climate Change, is the first to explore how local communities could be harmed by increasingly corrosive waters. Researchers found the threat of ocean acidification to U.S. fisheries is wider than previously understood. “It’s hitting a lot more of our coasts than we realized,” Lisa Suatoni, a co-author on the report and a senior scientist with NRDC’s oceans program, said. […] the NRDC team found that even bioregions in warmer waters face risks. A variety of local factors such as water pollution, lack of economic diversity and weak political action on environmental issues can all exacerbate problems posed by increasingly acidic waters. “When you look at these additive effects, we suddenly see more regions of the coast will be experiencing rapid ocean acidification,” Suatoni said. For instance, in the Chesapeake Bay on the East Coast, fertilizer pollution from nearby agricultural operations  — which also creates toxic algae blooms  — can accelerate the rate of acidification. Maryland and Virginia’s economies have already lost a combined $4 billion in the past three decades as pollution, disease, poaching and habitat destruction clobber clam and oyster farmers, according to a Chesapeake Bay Foundation report. Coastal Louisiana, another vulnerable region, also suffers from agricultural pollution. But many parishes face additional acidification risks because oyster farming is the only business in town. If the shellfish disappear, so will the jobs. “They don’t have the ability to rebound from harm,” Suatoni said of the communities. [more]

CO2 Emissions Threaten Seafood As Ocean Acidification Spreads Along US Coastlines