BY HUGH BAILEY
Hearst Connecticut Media
Connecticut is one of 15 states at serious risk of economic harm from ocean waters becoming more acidic and causing damage to the shellfishing industry, according to a new report.
Shellfishing generates more than $30 million a year and accounts for more than 300 jobs statewide, according to the state Department of Agriculture. Decades of worldwide fossil-fuel consumption have released more carbon dioxide than the oceans can safely absorb, and more carbon dioxide in the ocean increases its acidity and threatens various species, including shellfish.
And Connecticut’s problems run deeper.
“Connecticut’s story is different from someplace like Alaska,” said Lisa Suatoni, senior scientist at the Natural Resources Defense Council and one of many authors of the study. “Here it’s not as much about fossil fuels, but we have more nutrient pollution in the form of runoff.”
Nitrogen and phosphorus enter the Long Island Sound from overflowing wastewater treatment plants, leading to oxygen deficiency, or hypoxia. In 2012, 20 percent of the sound had oxygen levels too low to sustain life, according to the Connecticut Fund for the Environment.
Nitrogen spurs excess algae growth. “You see these algae blooms, and it all doesn’t get eaten by animals, so it sinks, gets eaten by bacteria, which also breeds and expires carbon dioxide, just like us,” Suatoni said. “So you have an additional source making the bottom waters of Long Island Sound more acidic.”
The study, in the journal Nature Climate Change, was published last week. It’s the first national assessment of vulnerability for ocean acidification, and it focuses on bivalves, like clams and oysters, which appear to be most endangered.
More than 70,000 acres of shellfish farms are under cultivation in the sound, according to the state. The shellfish account for about 70 percent of all fisheries revenue in the state.
The study did not focus on lobsters, whose numbers have dropped dramatically. In 1998, the state lobster catch hit a high mark of 3.7 million pounds. It dropped to 121,700 pounds in 2013, with varying explanations offered for the decline.
The key to reversing the acidification trend locally is improving the wastewater treatment systems that empty into the sound, Suatoni said.
“Here we can take local action to help reduce the problem,” she said. “Connecticut doesn’t need to rely on a global agreement on CO2 emissions. These local efforts are very important.”
Save the Sound, a program from the Connecticut Fund for the Environment, has spearheaded efforts to ensure that sewage treatment plants meet nitrogen standards. Connecticut has invested $2.5 billion in sewage treatment plant improvements in recent years, said Leah Schmalz, program director for CFE.
But more work remains, including on the New York side of the sound, which does not have the same nitrogen-prevention programs. Work to reduce stormwater runoff is also ongoing.
She said the report on shellfish vulnerability was eye-opening.
“It really became crystal clear the huge potential impact on the sound because of the hypoxia issue mixing with acidification,” she said.
This type of report can help bring home the consequences of ongoing carbon emissions, said David L. Downie, associate professor of environmental studies at Fairfield University.
“It’s another example of economic costs that will show up in places that people don’t expect, but will hit home,” he said.
Dramatic policy change usually requires extreme events, he said, which presents a difficulty in this case. “The challenge is that these impacts are slow moving. Climate change doesn’t have those extreme events, something that will hit people over the head. Reports like this help people understand it isn’t just going to be hot, there will be real economic impacts.”
He said the effects will be far-reaching.
“You think about examples from throughout history,” he said. “We’ve seen collapses in fisheries, and seen the ripple effects it has on local economies. It is significant.”
Hearst Connecticut Media includes four daily newspapers: Connecticut Post, Greenwich Time, The Advocate (Stamford) and The News Times (Danbury). See ctpost.com for more from this reporter.
