Saving Seafood

Here’s why scientists are worried about newly discovered underwater heat waves

March 27, 2023 — In a recent study, researchers discovered extreme warming along the seafloor of the North American continental shelves.

Continental shelves form the edge of the continent. They extend up to 300 miles out to sea and, compared to the majority of the ocean floor, have shallow water. Their shallow depths and relative proximity to land allow continental shelf waters to be productive.

For example, the bottom of continental shelves serves as critical habitats for commercial species such as lobsters, scallops, crabs, flounder, cod and other groundfish, according to the National Oceanic and Atmospheric Association (NOAA).

Read the full article at Fox Weather

Scientists Scramble to Help Bay Scallops Survive Climate Change

March 27, 2023 — Stephen Tettelbach was surveying the bay scallop population in Nantucket with colleagues late in the summer of 2019 when he got the call: A longtime friend and fisherman on Long Island reported a mass die-off of scallops in Peconic Bay, Long Island’s legendary fishery.

Tettelbach, head of the Peconic Bay Scallop Restoration Program at Cornell Cooperative Extension (CCE) in Suffolk County, New York, said his first response was denial. Peconic Bay’s prized shellfish had been thriving in June. In fact, it was supposed to be another banner season—commercial landings in the two preceding years had been the largest since 1994, topping 110,000 pounds.

But after returning to Long Island a few days later and setting out on his annual October surveys of Peconic Bay, an estuary nestled between eastern Long Island’s North and South Forks known for its pristine waters, lush eelgrass meadows, and scallops considered to be the best in the country, Tettelbach saw the devastation for himself. “There were almost no living scallops anywhere,” he remembers.

Once the country’s leading bay scallop fishery, Peconic Bay is now holding on for dear life. 2019 marked the first in a series of die-offs that has led to the collapse of one of the few remaining fisheries of wild bay scallops, whose native East Coast populations have declined dramatically in recent decades.

Coastal change in the Northeast is fast outpacing other areas, with summer water temperatures increasing at a rate more than twice the global average, according to research published in Global Change Biology in January.

Read the full article at Civil Eats

Ocean acidification, warming will slow sea scallop growth, study says

March 26, 2023 — A new study published in the journal PLOS Climate indicates that ocean acidification conditions projected between now and 2100 depress the growth of juvenile Atlantic sea scallops. Ocean acidification is caused by the ocean absorbing carbon dioxide from the atmosphere, resulting in chemical changes that increase acidity. Ocean warming may further hinder growth. Atlantic sea scallops support one of the most valuable fisheries in the United States, worth $670 million in 2021.

Postdoctoral researcher and lead author Emilien Pousse said, “This work describes the energetic balance of sea scallops under ocean acidification conditions for the first time, a species of economic and socio-cultural importance. Within our changing world, getting to know how our marine resources and fisheries could be affected by ocean warming and acidification in the near future is the key to anticipate the upcoming changes.”

The 8-week study was a collaboration between NOAA Fisheries and Massachusetts Maritime Academy in Buzzards Bay, Massachusetts. Faculty and students helped NOAA scientists conduct the study at the campus’ aquaculture lab. Scientists exposed the scallops to three different carbon dioxide levels and measured their growth and metabolism, including feeding, respiration, and excretion rates. Ocean acidification conditions significantly reduced the scallops’ ability to take up energy.

The NOAA Ocean Acidification Program, which funded this work, has a mission to better prepare society to respond to changing ocean conditions and resources by expanding our understanding of ocean acidification.

Dwight Gledhill, deputy director of NOAA’s Ocean Acidification Program, explained further. “Sea scallops represent a critically important fishery for New England and the Mid-Atlantic,” he said. “Because the effects of ocean acidification can vary considerably from species to species, it is necessary that we conduct targeted studies on sea scallops to better evaluate the risk ocean acidification may pose to them in coming decades.”

Dvora Hart is the lead assessment scientist for the species at NOAA Fisheries as well as a co-author of this study. She has studied Atlantic sea scallops for 24 years.

“This is the first information on post-larval scallop growth under ocean acidification,” she noted. “I previously worked on computer modeling studies with Woods Hole Oceanographic Institution oceanographers focused on climate change and ocean acidification effects on sea scallops. At the time, we did not have experimental data on sea scallop response. We estimated it based on what we knew about other scallop species and oysters. We now have real data on how sea scallops respond, filling a major gap in our knowledge.”

Read the full article at the National Fisherman

Phytoplankton blooms offer insight into impacts of climate change

March 23, 2023 — The first study into the biological response of the upper ocean in the wake of South Pacific cyclones could help predict the impact of warming ocean temperatures, New Zealand researchers believe.

Dr. Pete Russell, of the University of Otago’s Department of Marine Science, and Dr. Christopher Horvat, of the University of Auckland’s Department of Physics, have published a study on the oceanic biological effect of Cyclone Oma which passed near Vanuatu in 2019.

“While Oma was a relatively benign , it produced a massive phytoplankton  in its wake—the single most abnormal event in the history of South Pacific chlorophyll measurements,” Dr. Russell says.

“Such an extreme event can produce a large amount of biomass in a part of the  that is typically a biological desert. We don’t yet know about the fate of this biomass, but one possibility is that it could end up on the bottom of the ocean, sequestering carbon.”

Read the full article at phys.org

I’m a fishing boat captain. Green energy companies, government want to put me out of business

March 20, 2023 — Offshore wind energy might be killing whales, but there’s no question it’s killing American fishermen.

I’ve been a fishing boat captain for over 20 years. I live on an island in Maine and sail out of New Bedford, Mass. My brothers and cousins are lobstermen.

Fishing is the trade our family has plied for generations. We’re proud to practice the founding craft of our nation. When colonists first settled New England, they looked to the sea to sustain them. And so it is for our coastal communities four centuries on.

Read the full article at Fox News

Marine heatwaves are sweeping the seafloor around North America

March 14, 2023 — Heatwaves unfolding on the bottom of the ocean can be more intense and last longer than those on the sea surface, new research suggests, but such extremes in the deep ocean are often overlooked.

A team of scientists with the U.S. National Oceanic and Atmospheric Administration have conducted the first assessment of marine heatwaves along North America’s continental shelves.

They found that these bottom heatwaves ranged from 0.5 degrees Celisus to 3C warmer than normal temperatures and could last more than six months — much longer than heatwaves at the surface.

Read the full article at Reuters

Algal Blooms Have Boomed Worldwide

March 3, 2023 — Algal blooms are growing bigger and more frequent worldwide as ocean temperatures rise and circulation patterns change.

Climate change is likely one cause of the alterations, which favor the growth of phytoplankton, according to a new study published in Nature.

Whether it’s good or bad is a murky question. Algae are an important food source for many marine animals, and large blooms can sometimes be a benefit for ocean ecosystems and fisheries.

But some algal blooms also release toxins into the water and poison the environment. And when blooms die off and begin to decompose, they can reduce the oxygen concentrations in the water, harming the ecosystem.

Read the full article at the Scientific American

Tuna species productivity and size may decrease due to climate change

March 1, 2023 — Understanding how climate change and fishing pressure affect major commercial species productivity and body size is key to being able to adapt and ensure the future sustainability of the fisheries.

In this context, a team from Spain’s Ciencia y tecnología marina y alimentaria (AZTI) has coordinated a study, published in Global and Planetary Change, in which the projections in  and swordfish productivity and body size in the future under different climatic and fishing scenarios have been analyzed. A model that includes many mechanisms that represent the population dynamics of different species and the competition between them has been used for this purpose.

“We wanted to know how the climate change and fishing pressure is going to impact some of the most commercially important species in order to make decisions to ensure the future of the resources,” says Maite Erauskin-Extramiana, the AZTI researcher who led the study.

Read the full article at PHYS.org

Gulf of Maine sees second-hottest year on record, report shows, ‘getting to the edge of habitability’

February 27, 2023 — Already one of the fastest-warming bodies of water in the world, the Gulf of Maine recorded its second-hottest year ever in 2022, another ominous indicator of how global warming threatens the rich marine world off New England.

The Gulf of Maine Research Institute reported recently that average annual sea surface temperature for the sprawling ocean waters clocked in at 53.66 degrees Fahrenheit last year, more than 3.72 degrees above a 30-year average measured earlier this century. In 2021, the average annual sea surface temperature was even slightly higher, at 54.09 degrees.

The rapid rise in water temperatures has dire consequences, such as the loss of marine species, some of which are major sources of food and commercial fishing activities, and rising sea levels that can damage coastal communities.

“It’s part of a multidecadal trend that … has profound implications for not just people who rely on the Gulf of Maine for their livelihoods and well-being but also for coastal communities,” said Dave Reidmiller, director of the Climate Center at the Gulf of Maine Research Institute.

Home to more than 3,000 aquatic species and birds, the gulf is “one of the most biologically productive marine ecosystems” in the North Atlantic, according to the Gulf of Maine Association. It covers a 36,000-square-mile area from the tip of Cape Cod to Cape Sable in Nova Scotia, and its historically cold waters are a key reason why the gulf is such a viable environment for marine life.

The temperature of the gulf has been rising rapidly for more than a century, at a rate more than three times that of the world’s oceans, according to the institute’s report released last week. It surpassed the average temperature of the global oceans in the 1990s.

Rising gulf temperatures are also, in large part, why New England itself is warming faster than the planetary average, scientists say.

Read the full article at the Boston Globe

“Blue foods” Can Tackle Global Malnutrition, Disease and Climate Change

February 27, 2023 — A new study has shown that foods that come from the ocean or freshwater, known as “blue foods,” have the potential to address several important global issues, including nutritional deficits, disease, and climate change.

The Blue Food Assessment is a worldwide collaboration of more than 100 scientists whose focus is on using blue foods to evaluate and develop healthy, equitable and sustainable food systems.

Blue foods are an incredibly diverse food source, with more than 2,200 wild species caught and over 600 farmed. Often, blue foods are more nutrient-rich, generate lower greenhouse gas emissions, and have less of an impact on land and water than many types of meat derived from land animals. But a new study has found that countries overlook the benefits of blue foods when developing nutritional, socioeconomic, and environmental policies.

“Even though people around the world depend on and enjoy seafood, the potential for these blue foods to benefit people and the environment remains under-appreciated,” said marine ecologist and member of The Blue Food Assessment, Ben Halpern.

In a new study, scientists at The Blue Food Assessment examined how blue foods were being accessed, produced and consumed globally, how production impacted the environment, and how they impacted nutritional and socioeconomic factors. The study highlighted four ways that blue foods improve food systems.

Read the full article at SeafoodSource