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 Study Shows Climate Change Could Reduce Scallop Population

October 3, 2018 — Researchers in Massachusetts say under the worst case scenario, climate change could reduce the scallop population by more than 50 percent in just a few decades, which could be bad news for New Bedford’s lucrative fishing port.

In 2016, commercial fishermen landed more than $300 million worth of fish at the Port of New Bedford, and 85 percent of that value came from scallops.

A new study from Woods Hole Oceanographic Institution shows as carbon emissions in the atmosphere increase, so does the acidity in the ocean.

Jennie Rheuban, lead author of the report, said that could affect how well scallops can grow.

“Adults may actually be growing slower and calcifying less quickly under these acidified conditions because it’s more difficult for them to lay down calcium carbonate as a shell,” Rheuban said.

Rheuban said ocean acidification could also cause scallops to become more vulnerable.

“They aren’t able to swim quite as well when they’re experiencing acidified conditions, and so we hypothesize that under acidification, scallops may be more susceptible to predation,” she said.

Read the full story at Rhode Island Public Radio

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

WHOI Warns Sea Scallop Fisheries of Rises in Ocean Acidification

September 26, 2018 — More than $500 million worth of Atlantic sea scallops are harvested off the east coast of the United States.

Scientists at the Woods Hole Oceanographic Institution (WHOI), however, warn that fisheries bringing in this massive catch might be in danger because of carbon-dioxide levels increasing in the Earth’s atmosphere, causing the upper oceans to become increasingly acidic.

“What’s novel about our work is that it brings together models of changing ocean environments as well as human responses. It combines socioeconomic decision making, ocean chemistry, atmospheric carbon dioxide, economic development and fisheries management, said the study’s lead author Jennie Rheuban.

“We tried to create a holistic view of how environmental changes might play out across different aspects of the sea scallop fishery.”

The scientists say the condition could reduce the sea scallop population by more than 50-percent within the next 30 to 80 years.

The predictions were made using a model created by WHOI scientists, which combines existing data and models of four major factors: future climate change scenarios, ocean acidification impacts, fisheries management policies, and fuel costs for commercial fishermen.

WHOI says that the ocean absorbs more than a quarter of all carbon dioxide in the atmosphere. They say that the acidity caused by this can corrode the shells of clams, oysters, and scallops, and event prevent their larvae from forming shells at all.

Read the full story at CapeCod.com

Warming seas are robbing some fish of their vital sense of smell

August 6, 2018 — There have been numerous wake-up calls about the effects of climate change on marine life. As ocean waters heat up, they are bleaching corals. Growing levels of carbon dioxide are acidifying seawater, which is degrading the shells and skeletons of sea organisms. The rising temperatures are prompting fish to migrate to colder waters, even causing them to shrink.

Now climate change is starting to affect their sense of smell, a phenomenon that will worsen in the coming years if global warming continues unabated, according to new research. A sense of smell is indispensable to fish. They use it to find food, detect imminent danger and elude predators, to find safe environments and spawning areas, even to recognize one another.

To lose it could threaten their very survival. If this happens, it also would mean big trouble for the fishing industry, tourism and, most importantly, global nutrition, since many of the world’s people — including its poorest — depend on fish for food.

“Future levels of carbon dioxide can have large negative effects on the sense of smell of fish, which can affect fish population numbers and entire ecosystems,” said Cosima Porteus, a researcher at the University of Exeter and author of the study, which appears in the journal Nature Climate Change.

“This can be prevented, but we must reduce carbon emissions now before it’s too late,” Porteus says.

Carbon dioxide combines with seawater to produce carbonic acid, which makes the water more acidic. Since the Industrial Revolution, oceanic CO2 has risen by 43 percent and is projected to be two and a half times current levels by the end of this century, according to the scientists.

Read the full story at Popular Science

The Ocean Is Getting More Acidic —What That Actually Means

June 18, 2018 — Grace Saba steadies herself on the back of a gently rocking boat as she and her crew slide a six-foot long yellow torpedo into the sea. A cheer erupts as the device surfaces, turns on its electronic signal, and begins a three-week journey along the New Jersey coast.

“It’s taken seven years to get this done,” said Saba, who has been working on this experiment since 2011. “I’m so happy, I think I might cry!”

Saba is an assistant professor of marine ecology at Rutgers University, where she is studying how fish, clams, and other creatures are reacting to rising levels of ocean acidity. Acidification is a byproduct of climate change; a slow but exorable real-life experiment in which industrial emissions of carbon dioxide into the atmosphere are absorbed and then undergo chemical reactions in the sea. Rising ocean acidity has already bleached Florida’s coral reefs and killed valuable oysters in the Pacific Northwest.

Now scientists like Saba want to know what might happen to animals that live in the Northeast, a region home to commercially important fishes, wild stocks of quahogs (clams), scallops, and surf clams that can’t swim away from growing acidic waters.

“They are just stuck there,” Saba said.

Saba’s torpedo-like instrument is actually an underwater drone, known as a Slocum glider, that is carrying an ocean acidity sensor. This is the first time that oceanographers have married the two technologies—glider and pH sensor—to get a big-picture view of changes underway in the commercially important fishing grounds of the Northeastern United States.

Read the full story at National Geographic

Ocean Acidification Could be a Net Positive for Some Fish

March 30, 2018 — One of the consequences of pumping more and more carbon dioxide into the atmosphere is the changing chemistry of the world’s oceans. Until now, the ocean has acted as a big sponge, soaking up about one-third of the CO2 released by human activities.

But now, scientists are watching a vast experiment unfold. All that carbon dioxide is triggering chemical reactions that is turning the oceans more acidic, which in turn is making life tough for lots of marine organisms. Oysters and other shellfish have been hit by die-offs in the Pacific Northwest and Gulf of Maine, while tropical reefs are dissolving faster than they can rebuild, according to a recent study in the journal Science.

Some researchers are seriously considering geoengineering to reverse the slow acidification of the ocean. Dissolving minerals like olivine or limestone into seawater would increase its alkalinity. (Remember the pH strip in your 10 gallon fish tank? Blue=alkaline, red=acidic.) Not only would that make it easier on marine life, but it would also allow the ocean-sponge to soak up more carbon dioxide from the atmosphere. Two British scientists proposed this idea last year in a paper in the journal Reviews of Geophysics, predicting that with a bit more research (and money) it may be possible to capture hundreds of billions to trillions of tons of carbon without messing up the marine ecosystem.

But this kind of massive planetary experiment needs lots of small-scale work in the laboratory before it’s ready. So in the meantime, marine scientists are trying to find which species will come out on top in a more acidic ocean.

In Sweden, a group of researchers tested survival in an artificially acidic ocean. In a fjord, they built an enclosed, floating test tube they called a “mesocosm” and filled it with phytotoplankton, zooplankton, and tiny herring larvae. Then they turned up the dissolved carbon dioxide, tracking herring survival over time as the acidity increased.

A similar lab experiment with codfish, another important Northern European food fish, killed off the fish. “Our surprise is that we didn’t find that,” said Catriona Clemmesen-Bockelmen, a marine ecologist from the GEOMAR Helmoltz Center for Ocean Research in Kiel, Germany, and a co-author on the study in Nature Ecology and Evolution. “Instead, we had a higher survival rate.” The herring, it seemed, liked the extra acidity.

Read the full story at Wired

 

NOAA site aims to help fishing communities bounce back

November 24, 2017 — NOAA Fisheries has introduced a new website designed to help fishing communities be more resilient in the face of climate change, fluctuating fish stocks and even declines in waterfront infrastructure and economy.

The new website endeavor, introduced this week after almost three years of planning, is called Community Resilience in the Greater Atlantic Region.

“It really came out of the strategic plan we developed here in the regional office, which was the first one anywhere,” said Peter Burns of NOAA Fisheries in Gloucester. “One of the goals of that plan centered on building community resilience to help strengthen fishing communities.”

Working with NOAA’s Northeast Fisheries Science Center in Woods Hole, the community resilience working group — which included NOAA staffers from the West Coast, as well — began exploring ways to assist fishing communities in coping with regulatory, environmental and economic changes that challenge the very sustainability of fishing communities.

According to NOAA Fisheries’ own description of the endeavor, the resiliency strategy would provide information on “solutions to improve groundfish business practices and economic vitality,” as well as incorporating climate change, ocean acidification and ecosystem analysis into NOAA Fisheries’ activities.

Read the full story at the Gloucester Times

Climate change: 5 signs it’s already begun in New Jersey

August 11, 2017 — By now, most are aware of the dire warnings: Climate change is coming and its effects are going to be especially painful for residents of the Jersey Shore.

While the timing of the truly catastrophic predictions remains fuzzy — Will the barrier islands be lost in 2050? 2100? Later? Sooner? — there are signs that irreversible change has already begun.

From economic and public health challenges to the more obvious outcomes of heat waves and rising seas, climate change has a foothold in New Jersey.

1. Migrating fish

There are about 3,000 commercial fishermen in New Jersey and thousands more who work at processing plants, wholesalers or in shellfishing.

“Fishermen knew about climate change a long time ago,” said Tom Fote, an officer with the Jersey Coast Anglers Association. “We started seeing stocks of fish moving farther north.”

As water temperatures rise, fish move northward, seeking deeper, cooler waters. Higher acidity in the ocean damages crabs, scallops, clams and other shellfish, according to the U.S. Environmental Protection Agency.

Read the full story at the Asbury Park Press

Senate Subcommittee Holds First Hearing to Guide Magnuson-Stevens Reauthorization

August 2, 2017 — The Magnuson-Stevens Act, the primary law regulating fisheries in federal waters, is in need of reauthorization, and Senate Commerce’s Subcommittee on Oceans, Atmosphere, Fisheries and Coast Guard on Tuesday held the first in a series of hearings to guide that process. And, unsurprisingly, the issue of climate change made waves.

Chris Oliver, assistant administrator of NOAA’s National Marine Fisheries Service, and John Quinn, chairman of the New England Fishery Management Council, pushed for a variety of changes, ranging from management of mixed stocks to more flexibility in how the Council Coordination Committee can monitor and collect data. But it was Sen. Richard Blumenthal who made the strongest case for change by criticizing the current system for failing New England’s fishing fleet and leaving the region’s fishermen “angry and frustrated beyond words.”

Because of climate change, Blumenthal said, fish that New England fishermen have traditionally sought were pushed north and fish from southern waters moved into New England. But catch limits for certain fish haven’t been adjusted to meet the reality facing New England fishermen, forcing them to return quota-exceeding fish to the ocean. Billions of dollars in profits are being lost, Blumenthal said, while fishermen from southern states come to New England waters to catch their migrating fish. “There is something profoundly unfair and intolerable about the situation,” he added. “In my view, it violates the present law.”

Quinn responded by pointing out that parts of the New England fishing industry are booming but agreed that groundfish fishermen are struggling. While the CCC’s process is to collect as much data as needed to produce accurate stock assessments, Quinn said they didn’t have “a simple solution for rising water temperatures or the ocean acidification,” which are the roots of the shifting fish populations.

Read the full story at Politico