Shrimp, oysters, crabs and other food from the ocean face little or no threat from acidic seas off the Lowcountry until the 22nd century — that was the word from global research on a potentially catastrophic consequence of carbon pollution.
Except more acidic waters already are killing coral reefs off Florida and coral has begun to bleach, or whiten as its organisms die off the South Carolina coast. Across the Southeast, commercial fishery and hatchery production are declining. Shellfish such as crabs appear to be declining, too, and shrimp might be. Research hasn’t been done to see if the acidity is a factor.
“We just don’t know enough,” said Kim Yates, a U.S. Geological Survey oceanographer, in maybe the scariest takeaway from the organizing meeting of the new Southeast Ocean and Coastal Acidification Network, held in Charleston last week.
The global research based its regional conclusion on worldwide data that included virtually no data from the Atlantic off the Southeast states because so little study has been done here.
The network plans to pull together “the state of the science” as it applies to the Southeast, bring in commercial anglers and other interests for their in-the-field observations, then develop plans to prevent the sort of ecosystem collapse that occurred on the West Coast with shellfish, said Debra Hernandez, network director.
“It’s not just an ocean problem. It’s impacting things right along the coast. We need to figure out how to manage that,” she said.
Acidification is occurring because fossil fuel burning is dropping carbon dioxide in the water, which eventually absorbs nearly one-third of the emissions. Chemical reactions from it leave the water more acidic, depleting shellfish such as shrimp and oysters, as well as “baseline” creatures: mollusks, phytoplankton and zooplankton that are fed on by food fish for larger species.
The loss of them would be a potentially catastrophic push in a cascading effect that could deplete the entire food chain, including the food humans eat.
The lack of diversity in commercially caught marine species makes the $21 million industry in South Carolina very vulnerable to more acidic waters, but there’s no data on what the hazards are here, whether and how species might adapt.
“There’s a lot of gaps in the research so far. We can infer what’s happening from other regions. (But) there’s such variability in the chemistry in the water off the Southeast,” said Libby Jewett, Ocean Acidification Program director for the National Oceanic and Atmospheric Administration. “Shellfish make up one-third to one-half the region’s commercial fishery, and we don’t know what the ramifications are.”
The good news is that experiments such as sea grass planting in the Tampa Bay area have been shown to cut down acidity in the waters, and the differences in the types of estuaries found from North Carolina to Florida make the rest of the region a natural laboratory for such experiments, meeting attendees concurred.
The biggest obstacle the network might have to overcome is a sometimes skeptical public with other priorities when there is no immediate crisis.
“The key question is how to get people aware that ocean acidification is part of the package (of marine pollution problems),” said Al George, South Carolina Aquarium conservation director.
“People are going to make decisions on what we’re going to do about this,” said Rick DeVoe, South Carolina Sea Grant Consortium director. “If shellfish beds get shut down, everybody knows there’s something going on and they start paying attention. We have the opportunity to get in front of (the problem) rather than the back end.”
The network is comprised of scientists, resource managers, business, nonprofit and government entities. For more information, go to secoora.org/socan.
Bo Petersen, The Post and Courier, 17 January 2016. Article.