Saving Seafood

Study: Marine Protected Areas Won’t Matter

May 10, 2018 — New research from the University of North Carolina concludes that most marine life in marine protected areas will not be able to tolerate warming ocean temperatures caused by greenhouse gas emissions.

There are 8,236 marine protected areas around the world covering about four percent of the surface of the ocean. They have been established as a haven to protect threatened marine life, like polar bears, penguins and coral reefs, from the effects of fishing and other activities such as oil and gas extraction.

The study found that with continued “business-as-usual” emissions, the protections currently in place won’t matter, because by 2100, warming and reduced oxygen concentration will make marine protected areas uninhabitable by most species currently residing in those areas.

The study predicts that under the Intergovernmental Panel on Climate Change’s Representative Concentration Pathway 8.5 emissions scenario, better known as the “business as usual scenario,” marine protected areas will warm by 2.8 degrees Celsius (or 5 degrees Fahrenheit) by 2100. Mean sea-surface temperatures within marine protected areas are projected to increase 0.034 degrees Celsius (or 0.061 degrees Fahrenheit) per year.

Read the full story at the Maritime Executive

 

Scientists: Climate change could punish fish habitats targeted for conservation

May 8, 2018 — Aquatic preserves created to protect sea life from Australia to the ocean off Mayport stand to lose huge numbers of fish as oceans warm in coming decades, researchers reported Monday.

The report in the journal Nature Climate Change concludes many of more than 8,000 places labeled as marine protected areas will be overtaken by effects of climate change without major reductions in carbon-dioxide releases worldwide.

“There has been a lot of talk about establishing marine reserves to buy time while we figure out how to confront climate change,” said Rich Aronson, a researcher at the Florida Institute of Technology in Melbourne who co-authored the report with seven other scientists. “We’re out of time and the fact is we already know what to do: We have to control greenhouse gas emissions.”

Marine protected areas have grown mostly unnoticed over a generation, spreading to include big chunks of Florida’s coastline. The Oculina Bank, for example, a stretch of deep coral reefs near Vero Beach, was just a “habitat area of particular concern” when the South Atlantic Fisheries Management Council attached a label to it in 1984. Rules against anchoring and fishing for snapper and grouper were added in the 1990s, then in 2000 the size more than tripled and new restrictions were added.

Read the full story at the Florida Times-Union

 

Sens. King, Collins push for more research on ocean warming in Gulf of Maine

May 1, 2018 — U.S. Sens. Susan Collins and Angus King have urged the federal government to improve efforts to understand the causes and effects of the rapid warming of the Gulf of Maine, which threatens to disrupt Maine’s traditional fisheries and the ecosystem that supports them.

“We need greater resources, enhanced monitoring of subsurface conditions, and a better understanding of the diversity of factors that are simultaneously impacting the Gulf of Maine, from changes in circulation and water temperature to ocean acidification,” the senators wrote in a letter Monday to the head of the National Oceanic and Atmospheric Administration, Tim Gallaudet.

“This effort is critical not just for Maine and New England states but for our country as a whole,” they added in the letter, which also called for greater cooperative research and monitoring efforts with Canada, which has sovereignty over the eastern half of the gulf. “Understanding the changes occurring in the Gulf of Maine with respect to warming ocean waters will allow us to better understand the impact to fisheries and benefit other waters similarly affected by climate change.”

Canadian scientists recently measured record-breaking temperatures in the deep water flowing into the principal oceanographic entrance to the Gulf of Maine – nearly 11 degrees above normal – and other researchers report warmer water has been intruding into some of the gulf’s deep-water basins. In a press release, the senators said their letter was prompted by an April 24 Press Herald story on these developments.

Read the full story at the Portland Press Herald

 

Bull Shark Nursery Grounds Shifting North, a Result of Climate Change

April 20, 2018 — The report published this week in Scientific Reports notes that while bull sharks have large migratory patterns and move quite a bit, they are very loyal to their nursery grounds.

Prior to this discovery, the most northerly known nurseries in the Atlantic were located off Florida’s east coast. In recent years, however, nurseries have been relocated north to the Pamlico Sound, which lies between the Outer Banks and North Carolina’s coast.

The discovery was a fluke, the researchers said.

While working to characterize shark habitat in North Carolina, the researchers from the North Carolina Division of Marine Fisheries, Simon Fraser University and East Carolina University found that a greater number of juvenile bull sharks, which remain at nursery grounds during their formative years, were reported in the brackish waters of Pamlico Sound.

Read the full story at the Weather Channel

 

The oceans’ circulation hasn’t been this sluggish in 1,000 years. That’s bad news.

April 11, 2018 — The Atlantic Ocean circulation that carries warmth into the Northern Hemisphere’s high latitudes is slowing down because of climate change, a team of scientists asserted Wednesday, suggesting one of the most feared consequences is already coming to pass.

The Atlantic meridional overturning circulation has declined in strength by 15 percent since the mid-20th century to a “new record low,” the scientists conclude in a peer-reviewed study published in the journal Nature. That’s a decrease of 3 million cubic meters of water per second, the equivalent of nearly 15 Amazon rivers.

The AMOC brings warm water from the equator up toward the Atlantic’s northern reaches and cold water back down through the deep ocean. The current is partly why Western Europe enjoys temperate weather, and meteorologists are linking changes in North Atlantic Ocean temperatures to recent summer heat waves.

The circulation is also critical for fisheries off the U.S. Atlantic coast, a key part of New England’s economy that have seen changes in recent years, with the cod fishery collapsing as lobster populations have boomed off the Maine coast.

Some of the AMOC’s disruption may be driven by the melting ice sheet of Greenland, another consequence of climate change that is altering the region’s water composition and interrupts the natural processes.

Read the full story at the Washington Post

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

 

Endangered status of Atlantic sturgeon up for review

March 27, 2018 — Federal fishing regulators say they are conducting a five-year review of threatened and endangered populations of Atlantic sturgeon.

Populations of sturgeon are listed as threatened in the Gulf of Maine and endangered in New York Bight, the Chesapeake Bay and off the Carolinas and South Atlantic.

The National Oceanic and Atmospheric Administration says the Endangered Species Act requires the agency to conduct the review to ensure the listings are still accurate. The listings are intended to be based on the best available scientific data.

The Atlantic States Marine Fisheries Commission said last year that a sturgeon stock assessment indicated the population is still very low compared to its historical abundance. They face threats such as climate change, ship strikes and fishing.

Sturgeon suffered overfishing in the 20th century when it was harvested for eggs for caviar.

Shortnose sturgeon are listed under the Endangered Species Act (ESA) as an endangered species throughout their range. Atlantic sturgeon are listed as five distinct population segments with those that hatch out in Gulf of Maine rivers listed as threatened, and those that hatch out in other U.S. rivers listedas endangered.

Once thought to number less than 100 in the Merrimack, the river’s shortnose sturgeon population has been on the rebound, researchers have said. Atlantic sturgeon are also found in the Merrimack, up to the Essex Dam in Lawrence.

Two distinct groups of adults, numbering more than 2,000, inhabit the river. One group includes fish born in Haverhill’s spawning grounds, while the other consists of fish born in Maine rivers such as the Kennebec and Androscoggin, which migrate to the Merrimack.

Researchers say that for much of the year, sturgeon are looking for food in the lower part of the Merrimack — from Amesbury to the Joppa Flats in Newburyport — and live there from November to March.

Haverhill is the only place in the river where sturgeon lay their eggs, and that happens in the spring.

Read the full story at the Gloucester Times

 

Warming world will affect fish size and fisheries

March 26, 2018 — Current fishery targets may become unachievable as the planet warms.

A new study, led by Plymouth Marine Laboratory (PML), has found that the proportion of large  in the North Sea may decrease as climate change unfolds, by as much as 60% in some areas. The effects of warmer waters and ocean acidification may mean proposed fisheries management targets based on fish size could be unachievable if the effects of  on fish size are not considered.

Using state-of-the-art modelling and comparison with real-life surveys, the researchers demonstrated they can simulate how fish size is changing in our marine environment, under the pressures of fishing and environmental factors. This form of modelling, combining important indicators and environmental change, can help with sustainable exploitation of fished stocks by helping policy makers consider how wild populations are impacted by changing, warmer and more acidic oceans into the future.

Indicators based on fish size are widely used in the study and management of wild populations exploited by commercial fishing. The Large Fish Indicator (LFI) is one such example, determining the biomass of fish above a certain size in a community, and used to inform policy and guide the .

While widely used, however, these types of indicators have not previously been used alongside predictions of future conditions in line with expected climate change. Fish size closely reflects the environment, and a warming world will change the conditions in which fish live. It has been suggested that rising water temperatures in the North Sea, for example, are driving down fish size in key species. By modelling North Sea fish populations alongside predicted  for LFI, scientists have shown how  may affect fish communities, and what it may mean for fisheries.

Read the full story at PHYS

 

Climate change threatens coastal life as we know it

March 9, 2018 — The Gulf of Maine is getting warm — quick. From 2004–2013, sea temperatures there rose faster than almost any other location on Earth.

Why it matters: The Gulf is home to a number of endangered species, and the fisheries there bring in several billion dollars per year to the U.S. and Canada, but the Gulf’s future hangs in the balance. Researchers are scrambling to understand what the warming water means for the people and animals who rely on the ecosystem, particularly as the changes there provide a glimpse into the future of coastlines around the world.

Why it’s warming

The Gulf of Maine lies at the intersection of several major ocean currents, including the Atlantic meridional overturning circulation, which moves dense, cold water down and toward the equator. Fresh water from melting sea ice seems to be weakening this current, which could be causing the Gulf to warm faster than other regions.

A combination of cold winters, warm summers, and dramatic tides make the Gulf one of the most productive ecosystems in the ocean. It’s a critical habitat for right whales, seabirds like puffins, humpback whales, bluefin tuna and other species.

Read the full story at Axios

 

These Chinook almost went extinct during California’s drought. Can this $100 million plan save them?

March 9, 2018 — During the worst of California’s five-year drought, thousands of eggs and newly spawned salmon baked to death along a short stretch of the Sacramento River below Shasta Dam.

The winter-run Chinook, already hanging by a thread, nearly went extinct.

Hoping to avoid a repeat of that dire scenario, fisheries officials announced Thursday the launch of a plan — nearly 20 years and $100 million in the making — they say would expand the spawning range of the fish to include a cold-water stream called Battle Creek. The idea is that the stream could keep the fragile winter-run alive as California’s rivers get hotter because of a warming climate.

The stakes are high and go well beyond the fate of the fish. Concerns about this run of salmon have a major impact on how water is distributed to farms and cities across California.

During the drought, for example, farmers experienced cuts to their water supply as dam managers held water in Shasta, the state’s largest reservoir, in a frantic effort to ward off extinction of the Chinook.

Read the full story at the Sacramento Bee