Saving Seafood

Fishermen, Scientists Collaborate to Collect Climate Data

May 23, 2016 — Fishermen plying the waters off the southern New England coast have noticed significant changes in recent years.  Though generations of commercial fishermen have made their livings on these highly productive waters, now, they say, they are experiencing the impacts of climate change.

“The water is warming up, and we see different species around than we used to,” says Kevin Jones, captain of the F/V Heather Lynn, which operates out of Point Judith, Rhode Island.

To help understand the ongoing changes in their slice of the ocean, Jones and other fishermen in the region are now part of a fleet gathering much-needed climate data for scientists through a partnership with the Commercial Fisheries Research Foundation (CFRF) and Woods Hole Oceanographic Institution (WHOI).

“There has been a lack of consistent measurements in this region, particularly across the continental shelf south of Rhode Island,” says Glen Gawarkiewicz, a physical oceanographer at WHOI and principal investigator on the project. “In order to understand the changes in ocean conditions and how those changes impact ecosystems and the people who depend on them, we need to collect more data, more often.”

The Shelf Research Fleet Project began in 2014 with that goal in mind. The fleet is made up of commercial fishing vessels that are fishing in or transiting through the study area throughout the year.

Read and watch the full story at the Woods Hole Oceanographic Institute

NOAA: Dungeness crab in peril from acidification

May 19, 2016 — The Dungeness crab fishery could decline West Coastwide, a new study has found, threatening a fishing industry worth nearly a quarter-billion dollars a year.

Scientists at the Northwest Fisheries Science Center in Seattle found that pH levels likely in West Coast waters by 2100 at current rates of greenhouse-gas pollution would hurt the survivability of crab larvae.

Increasing ocean acidification is predicted to harm a wide range of sea life unable to properly form calcium carbonate shells as the pH drops. Now scientists at the NOAA’s Northwest Fishery Science Center of Seattle also have learned that animals with chitin shells — specifically Dungeness crabs — are affected, because the change in water chemistry affects their metabolism.

Carbon dioxide, a potent greenhouse gas, is pumped into the atmosphere primarily by the burning of fossil fuels. Levels of atmospheric C02 have been steadily rising since the Industrial Revolution in 1750 and today are higher than at any time in the past 800,000 years — and predicted to go higher.

When carbon dioxide mixes with ocean water it lowers the pH. By simulating the conditions in tanks of seawater at pH levels likely to occur in West Coast waters with rising greenhouse gas pollution, scientists were able to detect both a slower hatch of crab larvae, and poorer survival by the year 2100.

Read the full story at the Seattle Times

Consortium pushes Atlantic pollock as sustainable alternative to cod in New England

May 13, 2016 — New England fishermen have caught more than 10 million pounds of Atlantic pollock every year since 2003, and now a loose consortium of proponents are advocating for its greater use as a cheaper alternative to cod and haddock.

As New England’s cod fishery has been damaged by slow reproduction, tight quotas and the impacts of climate change, a group of fishermen, processors, restaurateurs and sustainable seafood advocates are aiming to rebrand Atlantic pollock as New England’s fish, according to an Associated Press article.

Read the full story at Seafood Source

Ocean’s Oxygen Starts Running Low

May 3, 2016 — Climate change is doing more than warming the world’s oceans. It’s also making it harder for marine life to breathe.

Curtis Deutsch, associate professor at the University of Washington’s School of Oceanography, studies how increasing global temperatures are altering the levels of dissolved oxygen in the world’s oceans. Scientists have been warning that decreasing amounts of available oxygen will increase stress on a range of species, even as they also face the effects of rising temperatures and ocean acidification.

Deutsch’s latest research is untangling how much oxygen loss is linked to climate change and how much is due to normal variation in oxygen levels.

“As the climate goes up, the amount of oxygen will go down, but it’s really hard to look in the ocean to see that change,” he said.

Using an earth system modeling approach, Deutsch and scientists at the National Center for Atmospheric Research and the Georgia Institute of Technology mapped out changing oxygen levels across the world’s oceans through the end of the 21st century.

They found that it was possible to distinguish the impact of global warming from other sources of oxygen loss. As soon as 2030 to 2040, climate-driven declines in oxygen levels will be detectable in oceans all over the globe. In some places, like the southern Indian Ocean and parts of the eastern tropical Pacific and Atlantic basins, evidence of climate-linked deoxygenation is already apparent, while other regions won’t see changes by 2100.

Read the full story from Scientific American 

Research supports blaming warmer waters for lobster decline

May 2, 2016 — HARTFORD, Conn. — Connecticut researchers found no pesticides in lobsters collected in Long Island Sound in late 2014, a new study has found, boosting evidence that warming water temperatures are the main culprit in a huge crustacean decline that has decimated the local lobster industry.

The findings raise questions about restrictions Connecticut passed in 2013, amid concern over declining lobster stocks, limiting coastal use of pesticides that can control mosquito populations that transmit diseases, including the West Nile and Zika viruses.

Lobstermen supported the restrictions, believing pesticides contributed to lobster die-offs. Some municipal and environmental officials were opposed, saying the rules would restrict the use of effective mosquito-controlling pesticides that can protect public health and there was no proven connection between pesticides and lobster die-offs.

The renewed debate about pesticides and lobsters comes as concern grows about the Zika virus spreading to the U.S. from Latin America and the Caribbean. The virus is mainly spread through mosquito bites and causes mild illness or no symptoms in most people. But it can cause microcephaly, a severe birth defect in which babies are born with abnormally small heads.

Read the full story from the Associated Press at the New Jersey Herald

Lower oxygen level in oceans could be more prominent by 2030s

April 29, 2016 — Reduction in the amount of oxygen present in oceans is already evident in some parts of the world. But as per a new study, the loss of ocean oxygen would be more prevalent in larger sections of oceans between 2030 and 2040. Currently, climate experts can’t say for sure if the fluctuation in the oxygen level is due to natural causes or it is due to climate change.

Decline in ocean oxygen will leave fish, crabs, squid, sea stars and other marine life to face struggle in breathing. Matthew Long from National Centre for Atmospheric Research (NCAR) was of the view that loss oxygen in the ocean has been considered as one of the serious side effects of warming atmosphere.

Professor Long mentioned, “Since oxygen concentrations in the ocean naturally vary depending on variations in winds and temperature at the surface, it has been challenging to attribute any de-oxygenation to climate change”.

Scientists have explained that warming surface waters absorb less oxygen. The oxygen that is absorbed faces more trouble in travelling deeper into the ocean. The researchers have used the NCAR-based Community Earth System Model in order to study the impact of climate change.

Read the full story at Maine News Online

How will Fish in the Northeast Respond to Climate Change?

April 27, 2016 — A new study, published by the journal PLOS ONE found 82 species of marine fish and invertebrates in the northwest Atlantic (or the northeast US) to be vulnerable to climate change (A write up of the study by the New York Times can be found here). These 82 species encompass every commercially managed fishery in the region as well as a few popular recreational species and endangered species.

Not all species were predicted to experience negative effects from climate change – only about half were likely to be negatively affected. 20 percent will be positively affected by climate change and the rest will be neutral, said Jon Hare, NOAA oceanographer and lead author of the paper. However a majority of the species studied did show a high potential for a change in habitat distribution, which could create significant management challenges

“Peter Baker, director of Northeast U.S. oceans for the Pew Charitable Trusts, said the report should be a motivator for fishing managers to protect more ocean habitat and preserve marine species.”

Comment by Doug S. Butterworth, Marine Resource Assessment and Management Group, University of Cape Town

In this paper, Hare et al. report the results of the application of Vulnerability Assessment methodology to assess the extent to which abundance or productivity of species on the Northeast US Continental Shelf may alter in response to climate change. More particularly, they consider, inter alia, directional effects (whether negative, neutral or positive) and potential for changes in distribution. The determinations are based on expert opinions which lead the authors to draw firm conclusions, e.g. that climate change is expected to negatively affect about half the species they consider.

The environmental conditions associated with the habitat preferences of different species may be determined from empirical studies for which considerable data are available. Hence there is a clear basis in data and analyses to formulate the opinions that have been consolidated in this report.

What is much less clear, however, is what bases could defensibly have been used by experts to comment on directional effects for abundance and particularly productivity under projected changes in environmental variables under climate change. The productivity, and consequently to a large extent, the abundance, of a population of a fish or invertebrate species is driven by the (typically) annual recruitments to that population. The inferences drawn by these experts must consequently have been based on knowledge of how environmental variables affect such recruitment.

Yet the difficulties of reliably establishing such relationships are well known in fisheries assessment science. The classic article on this topic by Ram Myers (When do environment-recruitment correlations work?) pointed to the failure of almost all such relationships that had been proposed when tested with new data.

This then begs the questions of what bases the experts contributing inferences concerning directional effects to the Hare et al. study used for their determinations and how reliable those inferences might be. If they are reliable, why are they generally not being used in the fisheries assessments from which advice on catch limits is formulated?

I agree with Hare et al. when they argue that the expert opinions they collated “can guide future monitoring, research, and monitoring studies.” However, they go further to state that their results can be used by managers to “guide management actions” (they provide examples of species for which they suggest decreasing fishing mortality). Should they not first meet the burden of justifying the bases on which the experts who contributed to their study drew their inferences about directional effects, and also explain the associated implications for the reliability of knowledge about fishery recruitment-environmental variable relationships?

Read the original post at CFOOD

West Coast fisheries are at risk as climate change disturbs the ocean’s chemistry

April 20, 2016 — The West Coast’s abundant fisheries are at risk as the region’s waters become more acidic, a group of scientists warn.

Researchers from the West Coast Ocean Acidification and Hypoxia Science Panel released a report this month that projects dire changes to ocean chemistry and marine life, and recommends ways to avert it, including restoring kelp forests and eelgrass beds and combating marine pollution.

The panel convened in 2013 to study how global carbon emissions are lowering pH and reducing oxygen levels in the ocean off the West Coast.

“Although ocean acidification is a global phenomenon, emerging research indicates that the U.S.-Canadian West Coast will face some of the earliest, most severe changes in ocean carbon chemistry,” the report says.

Because of the way the Pacific Ocean circulates, the West Coast is exposed to more acidic water than other areas of the globe. Oyster production in the Pacific Northwest has already declined, as changes in ocean chemistry tamper with shell formation, and scientists warn that popular game fish and other species are also at risk.

Read the full story from the Los Angeles Times

Ocean souring on climate change

April 18, 2016 — The West Coast’s famously abundant fisheries are at risk as the region’s waters become more acidic, a group of scientists have warned.

The researchers, with the West Coast Ocean Acidification and Hypoxia Science Panel, this month released a report that projects dire changes to ocean chemistry and marine life, and recommends ways to avert it, including restoring kelp forests and eelgrass beds, and combating local marine pollution.

The panel, including Andrew Dickson, a professor of marine chemistry at Scripps Institution of Oceanography, convened in 2013 to study how global carbon emissions are lowering pH and reducing oxygen levels in the ocean off the West Coast.

“Although ocean acidification is a global phenomenon, emerging research indicates that the U.S.-Canadian West Coast will face some of the earliest, most severe changes in ocean carbon chemistry,” the report states.

Read the full story at The San Diego Union-Tribune 

Rising Carbon Dioxide Levels Threaten Corals and Oysters

April 5, 2016 — Tiny, thin-shelled oysters; crumbling coral reefs; fish unable to make sense of odors; decimated plankton populations. Those are some of the nightmare scenarios conjured by the prospect of a rapidly acidifying ocean caused by unchecked carbon dioxide emissions from fossil fuel burning.

Here’s the chemistry: when carbon dioxide and water mix, they form a weak acid, called carbonic acid. Add enough carbon dioxide, and the pH, or acidity, of the water will start to change. Of course, the ocean is a big place with a lot of water, and it naturally contains other chemicals that can help stabilize the pH.

On the other hand, the ocean has absorbed more than a quarter of all human-produced carbon dioxide since the industrial revolution. The result: globally, the pH of the ocean has dropped by an average of 0.1 pH units. That may not sound like much but, since the pH scale is logarithmic, it translates to a 25 to 30 percent increase in acidity. And, as ocean water becomes more acidic, the carbonate that many animals use to build their calcium skeletons and shells becomes scarcer.

Read and listen to the full story at WCAI