Saving Seafood

Scientists see stronger evidence of slowing Atlantic Ocean circulation, an ‘Achilles’ heel’ of the climate

February 26, 2021 — A growing body of evidence suggests that a massive change is underway in the sensitive circulation system of the Atlantic Ocean, a group of scientists said Thursday.

The Atlantic meridional overturning circulation (AMOC), a system of currents that includes the Florida Current and the Gulf Stream, is now “in its weakest state in over a millennium,” these experts say. This has implications for everything from the climate of Europe to the rates of sea-level rise along the U.S. East Coast.

Although evidence of the system’s weakening has been published before, the new research cites 11 sources of “proxy” evidence of the circulation’s strength, including clues hidden in seafloor mud as well as patterns of ocean temperatures. The enormous flow has been directly measured only since 2004, too short a period to definitively establish a trend, which makes these indirect measures critical for understanding its behavior.

The new research applies a statistical analysis to show that those measures are in sync and that nine out of 11 show a clear trend.

Prior research had suggested that the AMOC was at its weakest point in a millennium or more, and suggested a roughly 15 percent weakening since about 1950. But when it comes to the latest evidence, “I think it just makes this conclusion considerably stronger,” said Stefan Rahmstorf, an author of the research and an oceanographer with the Potsdam Institute for Climate Impact Research in Germany.

The study was published in Nature Geoscience by scientists from the Potsdam Institute, Ireland’s Maynooth University and University College London.

The AMOC is driven by two vital components of ocean water: temperature and salt. In the North Atlantic, warm, salty water flows northward off the U.S. coastline, carrying heat from the tropics. But as it reaches the middle latitudes, it cools, and around Greenland, the cooling and the saltiness create enough density that the water begins to sink deep beneath the surface.

Read the full story at The Washington Post

Why a net‑zero future depends on the ocean’s ability to absorb carbon

February 26, 2021 — Most of us growing up along Canada’s East Coast never worried about hurricane season. Except for those working at sea, we viewed hurricanes as extreme events in remote tropical regions, seen only through blurred footage of flailing palm trees on the six o’clock news.

Today, a warming ocean spins hurricanes faster, makes them wetter and drives them towards Atlantic Canada and even further inland. Hurricanes, winter storms and rising sea levels will continue to worsen unless we slow climate change.

The lifeblood of coastal economies and societies has always been the connection between land and sea, and that’s become more evident with climate change. But this isn’t just a coastal story anymore.

The oceans moderate the world’s climate through the absorption of heat and carbon. And just how much carbon the ocean will continue to absorb for us remains an open question. Whatever we do, it must be grounded in our growing wisdom of the deep connections between life on land and in the sea.

As Canada commits to a net-zero future and plans its post-COVID economic recovery, innovations and investments could backfire if they reduce the ocean’s ability to absorb our excesses.

Read the full story at PHYS.org

REPORT: CLIMATE CHANGE A MAJOR THREAT TO RECREATIONAL FISHING

February 24, 2021 — A new report by fly fishing industry leaders brings to light what scientists have long known: that fishing is suffering from the effects of climate change—and offers solutions.

The American Fly Fishing Trade Association and its nonprofit AFFTA Fisheries Fund released the report last week, which acknowledges, “Climate change is significantly affecting ocean ecosystems, the abundance and distribution of fish, and the nature of saltwater fishing.”

AFFTA sees the effects of climate change and overfishing as principal threats to fisheries that the fly-fishing industry has long fought to address. This blue-ribbon report offers a systematic approach to strengthen marine fisheries conservation and management, support recreational fisheries, and lead to more abundant marine fisheries in all U.S. ocean waters.

Though the report looks at these issues on a national scale, it offers many recommendations that apply to the Chesapeake Bay and its tributaries, from warming of upland coldwater brook trout streams to effects on oyster shells and loss of shoreline habitats. One particularly applicable example is the report’s commitment to work with coastal states to increase the size and distribution of seagrass beds, by improving water quality and planting grasses. It notes that coastal ecosystems like marshes and grassbeds are capable of absorbing carbon at rates up to four times those of forests on land.

Read the full story at Chesapeake Bay Magazine

As water temperatures rise, Rutgers scientists breed tougher shellfish

February 23, 2021 — Over the last half-century, global sea surface temperatures have been on the rise, but in the last decade they have increased at an accelerated rate.

New Jersey’s coastal waters, both along the Atlantic Coast and Delaware Bay, have been no exception. More alarming, recent research indicates that sea surface temperatures in the Northeast are warming two to three times faster than the global average. For instance, in 2012, water temperatures in the Mid-Atlantic reached the highest levels ever seen in over 150 years of recorded observations.

This rapid increase in water temperature is already influencing New Jersey’s marine species. Breeding habits, ranges and growth rates are adjusting as the environment in which they have evolved to thrive has changed at an unnatural pace. For the commercial fishermen and women whose livelihoods depend on the state’s fishery, particularly those who are only just beginning to experiment with shellfish aquaculture, warmer waters mean higher operational risk.

A new study from the Rutgers University Haskin Shellfish Research Laboratory, which has been monitoring New Jersey’s shellfish stocks for more than a century, is working to combat the impacts of climate change by selectively breeding bay scallops and surf clams that can grow faster and tolerate higher water temperatures.

Read the full story at NJ Spotlight News

Part I: Emergency Actions on IFQ Fisheries And Review of Climate Change at February NPFMC Meeting

February 22, 2021 — The North Pacific Fishery Management Council (NPFMC) sent Emergency Rule requests to NOAA Fisheries on halibut and sablefish license requirements for the second year in a row due to the pandemic, while reviewing several reports related to climate change: the Bering Sea FEP Plan Team report, the Climate Change Taskforce (CCTF) workplan, an update from the Local Knowledge, Traditional Knowledge and Subsistence (LKTKS) Taskforce, and a report from the Ecosystem Committee.

The request to modify transfer provisions in the halibut and sablefish individual fishing quota (IFQ) fishery was the same as last years, which accommodates restrictions in place due to COVID-19 travel constraints and  health and safety mandates.

Read the full story at Seafood News

Lobster research explores ocean warming effects

February 22, 2021 — A team of researchers from the University of Maine’s Darling Marine Center in Walpole and Bigelow Laboratory for Ocean Sciences in East Boothbay and the Maine Department of Marine Resources in West Boothbay Harbor recently published their research on the effects of ocean warming and acidification on gene expression in the earliest life stages of the American lobster.

The work was published in the scientific journal Ecology and Evolution with collaborators from the University of Prince Edward Island and Dalhousie University in Canada.

The team’s experiments examined the gene regulatory response of post-larval lobsters to the separate and combined effects of warming and acidification anticipated by the end of the 21st century. They found that genes regulating a range of physiological functions, from those controlling shell formation to the immune response, are either up- or down-regulated. Importantly, they observed that the two stressors combined induced a greater gene regulatory response than either stressor alone.

Read the full story at The Ellsworth American

Warming seas could wipe out Snake River chinook by 2060, scientists predict

February 19, 2021 — Snake River spring-summer chinook could be nearly extinct by 2060 and interventions are “desperately needed” to boost survival in every stage of their lives, scientists warn.

The findings, published Thursday in the journal Communications Biology, modeled survival of eight populations of wild Snake River Basin spring-summer chinook during the ocean phase of their life, under various climate-warming scenarios.

Salmon hatch in rivers, but mature for years at sea before they return to the waters of their birth. It is a perilous life cycle that could become all but impossible for some already fragile salmon populations that make one of the most arduous of all journeys, all the way to Idaho. They travel more than 1,800 miles round trip, climb more than a mile in elevation, and tackle eight dams, each way: four on the main stem Columbia, then four more on the Lower Snake River.

Add just a little ocean warming, and it’s curtains. Populations declined in all eight basin chinook populations for which the scientists ran predictions. Just a little more than 1 degree Celsius temperature increase in sea-surface temperature produced dire effects — with mortality as high as 90% in warmer seas.

Read the full story at The Seattle Times

Washington state salmon report offers warning to Alaska

February 17, 2021 — A report on Washington state’s dwindling wild salmon populations offers a warning to Alaska, where several stocks have registered concerning declines over the past years.

Washington’s 2020 State of the Salmon in Watersheds report chronicled a bleak panorama, with 14 of the state’s species listed as endangered. While conversation efforts have succeeded in revitalizing some salmon runs in Washington, the report said fish stocks in the Pacific Northwest face an uphill battle.

Read the full story at Seafood Source

Climate change challenges trout industry in North Carolina

February 17, 2021 — Raising trout in Western North Carolina is a time- and labor-intensive process, and the growing threat of climate change only worsens the situation, creating difficulties for hatcheries and recreational fisherman.

Producing trout even in optimal conditions is challenging. “It’s 35 seasons of disaster,” joked Adam Moticak, superintendent of the N.C. Wildlife Resources Commission’s Bobby N. Setzer State Fish Hatchery in Brevard.

The Setzer facility, one of three cold-water trout hatcheries run by the state’s Wildlife Resources Commission, raises fish to support the booming sport fishing industry in Western North Carolina, a $383 million venture in 2014 that supported more than 3,500 jobs.

But sport fishing is only one part of the North Carolina trout industry affected by climate change. Farmers who raise fish to sell to restaurants and retailers, fishing guides who make their living on the water and conservationists who look for wild trout as indicators of a healthy ecosystem face mounting concerns about climate change.

While Idaho leads the country in trout production with 40 million pounds of fish a year, North Carolina ranks second, producing 5 million pounds of trout annually. Climate change threatens the economic state of this thriving industry.

Read the full story at the Carolina Public Press

Rising water temperatures could be a death sentence for Pacific salmon

February 12, 2021 — In the Pacific Northwest, several species of salmon are in danger of extinction. The Washington State Recreation and Conservation Office has released a report on the state of salmon populations in the state’s watersheds—and the findings predict a grim future.

The report was commissioned by the Governor’s Salmon Recovery Office, established by the state legislature in 1998 in response to the Salmon Recovery Planning Act. Its findings showed that 10 to 14 species of  in the northwest are “threatened or endangered,” and five species are “in crisis.”

The findings, though alarming, are in line with population trends over the last few decades. The once prolific salmon populations in Washington State have been declining for years, and populations are now estimated to be at about 5% of historic highs.

The five species of salmon and steelhead that the report found to be most at risk are Snake River spring/summer chinook, Puget Sound chinook, Lake Ozette sockeye, Upper Columbia River spring chinook, and Puget Sound steelhead—a sampling that covers a wide geographic area in the state.

Read the full story at PHYS.org