Climate change is responsible for a number of threats to the U.S. shellfish industry. In recent years, Washington State’s $270 million shellfish industry has been scrambling to address productivity losses due to ocean acidification, caused by a significant increase in carbon dioxide emissions that began at the start of the industrial revolution. In highly acidic water, it is difficult for shellfish larvae to create shells from calcium carbonate because the water is too corrosive. In 2007 and 2008, Pacific Northwest shellfish larvae hatcheries saw their output plummet by up to 80 percent. By enacting strict water pH monitoring practices, these hatcheries have largely recovered, but the larger seafood industry is under threat as oceans continue to acidify, which threatens the health of wild shellfish as well as coral, which are vital parts of oceanic ecosystems.
Now, new research has illuminated another climate-related threat to the shellfish industry. Scientists have documented a link between warming seawater and an uptick in Vibrio bacteria. Humans who come into contact with these bacteria through various pathways, such as by consuming raw oysters that harbor the organisms or by swimming in water in which the bacteria live, can become very ill if the bacteria are present in high densities.
The study provides empirical evidence that a change in water temperature is the cause of the growth of Vibrio, but the correlation has long been suggested by medical evidence. According to an Associated Press article about the new study, the Centers for Disease Control and Prevention reports that lab-confirmed Vibrio infections in the United States have increased from an annual average of about 390 in the late 1990s to 1,030 in recent years—and in those recent cases, an average of 100 infections per year prove fatal.
For a number of years, the U.S. Food and Drug Administration (FDA) has been considering requiring oyster producers to sterilize oysters pulled from the Gulf Coast, due to an increase in illnesses reported in that region, especially during the warmest months. In May, a consumer group filed a suit against the FDA, saying it is moving too slowly toward setting stricter regulations on oyster growers. But the East Coast Shellfish Growers Association (ECSGA) strongly resists any efforts to force growers to adopt sterilization techniques, even if only during part of the year and only along the Gulf Coast, on the grounds that this would diminish U.S. producers’ competitive advantage.
On its website, the ECSGA posted the following: “As an industry our fear is that this is a slippery slope and the FDA really wants to mandate sterilization of all shellfish. This would open the door to cheap, sterilized shellfish from Asian nations where shellfish are grown in filth. Our only market advantage is that we can offer fresh live shellfish – once we lose that advantage our markets will evaporate.”
The Associated Press’ article about the study caught my attention because, earlier this summer, we reported on how Daniel Ward, an entrepreneur and researcher who operates a 10-acre aquaculture operation in Megansett Harbor, on Massachusetts’ Cape Code, is experimenting with thermal cameras and temperature trackers, communicating over a cellular network provided by Verizon, to track the temperature of his oyster harvest—specifically to address the threat posed by Vibrio bacteria.
Vibrio—particularly two types, Vibrio vulnificus and Vibrio parahaemolyticus—are not being introduced due to climate change. They’ve always been present, though they proliferate when the water is warmest.
Ward says tests have shown that neither Vibrio vulnificus or Vibrio parahaemolyticus are present in the water at his farm or in the oysters he grows.
Hopefully, the technology that Ward is piloting will prove effective in keeping his customers’ customers healthy, and his business growing. If it does, others in the industry might take the same or similar approaches to tracking the temperatures to which oysters are subjected.
“I’m looking for ways to make aquaculture more economically and environmentally viable,” Ward told me back in April, “through better output and better tech.”
The only lasting approach to stemming these economic threats—and innumerable other and far more severe threats related to climate change—is to reduce CO2 emissions through sweeping changes in how we produce and consume energy and other resources. But as businesses, governments and individuals work toward that goal, IoT technologies can serve as useful tools to help us monitor and track complex events and systems. Perhaps if oyster growers can show that more precise monitoring, through the use of IoT technology, can insure that their products are safe for human consumption, they will be able to avoid sterilizing oysters and maintain their farm-fresh advantage.
Note: An earlier version of this piece indicated that Vibrio vulnificus and Vibrio parahaemolyticus are present at Daniel Ward’s farm. They are not and that has been corrected in the story. I also came away from my April interview with Ward with misunderstandings about the impact that temperature management plays in the growth of these bacteria when they are present in oysters, and have removed references to that. I regret these errors. –Mary Catherine O’Connor
Mary Catherine O’Connor is the editor of IoT Journal and a former staff reporter for RFID Journal. She also writes about technology, as it relates to business and the environment, for a range of consumer magazines and newspapers.