Tag Archives: PMEL

Washington’s Promising Pollution Story Starts With Oysters And Ends With Victory

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ThinkProgress.com, by Natasha Geiling

Oct 28th, 2015

When Alan Barton first arrived at Whiskey Creek Shellfish Hatchery in 2007, he wasn’t expecting to stay very long. The hatchery — the second-largest in the United States — was in trouble, suffering from historically high mortality rates for their microscopic oyster larvae. But Barton knew that in the oyster industry, trouble is just another part of the job.

As manager of the oyster breeding program at Oregon State University, he had already helped one oyster larvae breeding operation navigate through some tough years in 2005, when a bacterial infection appeared to be causing problems for their seeds. To combat the issue, he had created a treatment system that could remove vibrio tubiashii, an infamous killer in the oyster industry, from the water.

Barton made the winding two-hour drive up the Oregon coast from Newport to Netarts, thinking his machines could easily solve whatever was plaguing Whiskey Creek. But when Barton’s $180,000 machine turned on, nothing changed. The hatchery was still suffering massive larvae mortality — months where nearly every one of the billions of tiny larvae housed in the hatchery’s vast network died before it could reach maturity.

Two-hundred miles up the coast in Shelton, Washington, Bill Dewey was also stumped. As director of public affairs for Taylor Shellfish, the country’s largest producer of farmed shellfish, he couldn’t figure out what was causing the hatchery’s tiny larvae to die in huge numbers. He knew aboutvibrio tubiashii, so when the die-offs began, Dewey called Barton and asked if they could install his machines at Taylor Shellfish’s own hatchery in the Puget Sound. And like at Whiskey Creek, the machines did little to stop the mysterious waves of death that were consuming the hatchery’s oyster larvae.

Back in Oregon, a National Oceanic and Atmospheric Administration (NOAA)-vessel rocked by persistent summer winds was approaching Newport. Dick Feely, a senior scientist with NOAA’s Pacific Marine Environmental Laboratory, was just halfway through the first-ever survey meant to measure the amount of carbon dioxide in the surface waters of the Pacific Coast. Already, he could tell from the few samples they had collected that he and his team had the material for a major scientific paper. He called his boss at NOAA to tell him that there was something wrong with the water. It seemed that an increase in carbon dioxide in the atmosphere, propelled by the burning of fossil fuels, was also increasing the acidity of the water.

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Acid Seas Threaten Creatures that Supply Half the World’s Oxygen

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Ocean acidification is turning phytoplankton toxic. Bad news for the many species – us, included – that rely on them as a principal source of food and oxygen.

June 16th, 2014 By Martha Baskin and Mary Bruno, crosscut.com

What happens when phytoplankton, the (mostly) single-celled organisms that constitute the very foundation of the marine food web, turn toxic?

phytoplankton pseudonitzschia_Their toxins often concentrate in the shellfish and many other marine species (from zooplankton to baleen whales) that feed on phytoplankton. Recent trailblazing research by a team of scientists aboard the RV Melville shows that ocean acidification will dangerously alter these microscopic plants, which nourish a menagerie of sea creatures and produce up to 60 percent of the earth’s oxygen.

The researchers worked in carbon saturated waters off the West Coast, a living laboratory to study the effects of chemical changes in the ocean brought on by increased atmospheric carbon dioxide. A team of scientists from NOAA’s Fisheries Science Center and Pacific Marine Environmental Lab, along with teams from universities in Maine, Hawaii and Canada focused on the unique “upwelled” zones of California, Oregon and Washington. In these zones, strong winds encourage mixing, which pushes deep, centuries-old CO2 to the ocean surface. Their findings could reveal what oceans of the future will look like. The picture is not rosy.

Scientists already know that ocean acidification, the term used to describe seas soured by high concentrations of carbon, causes problems for organisms that make shells. “What we don’t know is the exact effects ocean acidification will have on marine phytoplankton communities,” says Dr. Bill Cochlan, the biological oceanographer from San Francisco State University oceanographer who was the project’s lead investigator. “Our hypothesis is that ocean acidification will affect the quantity and quality of certain metabolities within the phytoplankton, specifically lipids and essential fatty acids.”

Acidic waters appear to make it harder for phytoplankton to absorb nutrients. Without nutrients they’re more likely to succumb to disease and toxins. Those toxins then concentrate in the zooplankton, shellfish and other marine species that graze on phytoplankton.

Consider the dangerous diatom Pseudo-nitzschia (below). When ingested by humans, toxins from blooms of this single-celled algae can cause permanent short-term memory loss and in some cases death, according to Dr. Vera Trainer, an oceanographer with NOAA’s Fisheries Marine Biotoxins Program. Laboratory studies show that when acidity (or pH) is lowered, Pseudo-nitzschia cells produce more toxin. When RV Melville researchers happened on a large bloom of Pseudo-nitzschia off the coast of Point Sur in California, where pH levels are already low, they were presented with a rare opportunity, explains Trainer, to see if their theory “holds true in the wild.”

Multiple phytoplankton populations became the subjects of deck-board experiments throughout the Melville’s 26-day cruise, which began in mid-May and finished last week.

Another worrisome substance is domoic acid, a neuro-toxin produced by a species of phytoplankton. Washington has a long history of domoic acid outbreaks. The toxin accumulates in mussels and can wind up in humans. “Changes in the future ocean could stimulate the levels of domoic acid in the natural population,” says Professor Charles Trick, a biologist with Western University in Ontario, and one of the RV Melville researchers. Which means that the acidified oceans of tomorrow could nurture larger and more vigorous outbreaks of killer phytoplankton, which could spell death to many marine species.

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