Saving Seafood

Scallop fishery may be imperiled by acidic seas

October 16, 2018 — Increasingly acidic seas pose a serious threat to the sea scallop fishery, a recent collaborative study by the University of Virginia, the Ocean Conservancy, the NOAA Northeast Fisheries Science Center, and the Woods Hole Oceanographic Institution (WHOI) concluded.

“As levels of carbon dioxide increase in Earth’s atmosphere, the oceans become increasingly acidic — a condition that could reduce the sea scallop population by more than 50 percent in the next 100 years under a worst-case scenario,” the study states. Models from the study, which were published recently in the journal PLOS One, combine existing data with several factors that impact the fishery: “future climate change scenarios, ocean acidification impacts, fisheries management policies, and fuel costs for fishermen.” Those factors were modeled out into 256 different possibilities.

Oceans absorb vast quantities of carbon dioxide. Fossil fuel emissions exacerbate what the oceans take in, further acidifying the water. “That acidity can corrode the calcium carbonate shells that are made by shellfish like clams, oysters, and scallops, and even prevent their larvae from forming shells in the first place,” the study states.

“[The scallop fishery is] healthy and valuable today in part because it is very well managed,” says Scott Doney, a co-author from WHOI and the University of Virginia. “We also used the model to ask whether management approaches could offset the negative impacts of ocean acidification.”

It couldn’t. In every scenario, elevated carbon dioxide levels created acidiferous ocean water. The culprit, the study concluded, was “unabated carbon emissions.”

Read the full story at the MV Times

New model looks at ocean acidification and sea scallop population drop

September 28, 2018 — Scientists at the University of Virginia and the Woods Hole Oceanographic Institution have created a new model looking at ocean acidification.

According to a release, fishermen harvest more than $500 million worth of Atlantic sea scallops each year off the East Coast, but this model predicts those fisheries may be in danger.

It says, as the levels of carbon dioxide increase in the atmosphere, the oceans become increasingly acidic, which could reduce the sea scallop population by more than 50 percent in the next 100 years, as a worst-case scenario.

The researchers say strong fisheries management and efforts to reduce CO2 emissions might slow or potentially even stop the trend.

“Rising atmospheric carbon dioxide levels pose a threat to many types of marine life, particularly shellfish,” said Scott Doney, an environmental sciences professor at UVA. “The ocean removes about a quarter of the carbon dioxide humans release to the atmosphere each year from fossil fuel use and deforestation. The resulting acidification of seawater makes it more difficult for shellfish like scallops and clams to build and maintain their shells.”

There are currently no studies that have been published showing the specific effects of ocean acidification on the Atlantic sea scallop, so to estimate the impact, Doney and his colleagues used a range of effects based on studies of related species.

The release says the new models lets scientists explore how plausible impacts of ocean acidification may change the future of the scallop population.

The researchers tested four different levels of impact on each of four different factors in the model, creating 256 different scenario combinations.

Read the full story at WCAV

Muddled communications on mercury causing consumer confusion

June 6, 2018 — It’s a rare occasion when representatives of industry, academia, and government all agree.

The fact that the U.S. seafood industry, an army of health experts, and the U.S. government all want to see the country’s population consume more seafood is a sign of how universal the agreement is surrounding the health benefits of seafood consumption.

But in seeking to achieve that objective, consensus often breaks down over the best way to communicate the benefits to consumers. One of the biggest points of division is the issue of mercury contamination in fish, since scientific studies on the potential harm of mercury in seafood are often conflicting and a source of frustration to consumers.

Jay Shimshack, an asssociate professor of public policy and economics at the University of Virginia and an expert in environmental and health policy, told SeafoodSource the problem lies with the way policymakers frame the message when issuing health advisories.

“Fish consumption advice is often complex and confusing. Message-framing matters a lot, and real-world constraints like affordability are as important as the true risks and benefits,” Shimshack said.

Consumers are told eating a variety of fish can be good for them, Shimshack said.

“But [they are told], ‘Do not consume some species [and be] careful not to consume too much of other species,’” Shimshack said. “Current U.S. commercial fish advisories list more than 60 species, and species names are not always consistent from one time and place to the next.”

Read the full story at Seafood Source