Ocean Acidification Takes Toll On Northwest Shellfish

Nov 28, 2012

Governor Chris Gregoire has just released a long awaited report on ocean acidification.

Oyster's being harvested.
Credit Photo Credit: Peter Gugerell/Wikimedia Commons

At a public ceremony Tuesday she announced 3.3 million in funding for the execution of some of the report’s recommendations. Some of the money will also go towards the creation of a new center at the University of Washington to study ocean acidification.

John Lentz has been farming shellfish in Puget Sound for 25 years.

He’s sorting through piles of oysters, hand picking the ones that are big enough to be sent to market.

Lentz: “It’s not a real exciting process is it?”

The oysters grown here at Chelsea Farms are known as “Chelsea Gems”. They average around 3 inches long. They’re perfectly cup-shaped and ready for decadent displays at oyster bars in Manhattan, Las Vegas and beyond.

Lentz pries open the tough, scab-like shell of one particularly attractive oyster.

Lentz: "You want to get the juice and chew the oyster…These taste a little like cucumber or some aftertastes like that. Fairly mild."

His daughter Shina Wysocki explains.

Wysocki: "When people describe wine they describe the terroire of wine or beef and so we call it meroire when it’s the flavor of the bay that it’s grown in and every farmer will tell you that their bay has the best tasting water."

The waters of Washington are home to a 270 million dollar shellfish farming industry - the largest in the country.

And if shellfish growers - like John and Shina - are in touch with their meroire enough to taste subtle cucumber undertones in the flesh of their oysters, it should come as no surprise that they are the first to witness - and sound the alarm - about the changes in water quality that affect their crop.

Here’s what happened.

Back in 2005 shellfish hatcheries in Washington and Oregon began seeing larval oysters dying by the billions.

They connected with scientists who did some testing and found out that the water coming into the hatcheries was becoming so corrosive that it was eating away at the oyster shells before they could form.

That meant farmers like Shina and her dad weren’t able to get enough larval oysters or “seed” to grow on their mudflats – and the problem isn’t going away.

Wysocki: "The nursery we buy from is calling with bad news because there’s no seed to ship and our employees work hard all summer to get ready and then there’s no babies to put out and that’s sad, y’know?"

There are a combination of factors that are making the ocean more acidic.

Number one – global CO2 emissions – from burning fossil fuel.

Dick Feely: "Approximately a quarter of CO2 that’s released in the atmosphere gets taken up by the oceans every year."

That’s Dick Feely, a scientist with the National Oceanic and Atmospheric Administration and one of the authors on the Governor’s new report. You might call him the grandfather of ocean acidification research. For the past 40 years he’s been studying how the ocean absorbs our CO2 emissions. It’s a pretty simple reaction - CO2 reacts with water to form carbonic acid.

Feely: “So we assumed the oceans would be a great reservoir for this excess CO2. What we didn’t know until about 20 years ago is that the consequences of that uptake of CO2 had serious implications for our ocean ecosystems.”

The report estimates that in Puget Sound alone more than 30 percent of marine species are vulnerable to ocean acidification.

But the CO2 that’s making the world’s oceans more acidic isn’t just coming from power plants in china or your tail pipe.

Some of it comes from algae.

Algae occur naturally, of course, but human activity along the coast – like farming runoff, leaky septic tanks or waste-water outflows can add nutrients to the water – which basically fertilizes the algae. And all those algae blooms – which happen every year in Puget Sound – eventually sink to the bottom and act sort of like a direct deposit of acidity to the coastal environment.

Scientists don’t know how much of the acidification problem is to blame on algae, natural upwellings, or on burning fossil fuels.

The report calls for further research on that. It also calls for continued monitoring of pH levels in coastal waters and limiting of local water pollution.

The report does lay out some strategies for adaptation - like breeding shellfish that are resistant to acidic waters, planting native sea-grasses to absorb more CO2 – and even sprinkling the coast with leftover shells from restaurants to make the water less acidic – sort of like taking a Rolaid.

But Bill Dewey, a spokesman for Taylor Shellfish and one of the authors of the report, says these measures won’t be enough.

Dewey: "Adaptation and remediation is a short term solution for a few species. The broader sense of the open ocean this is a huge problem and it’s going to change dramatically and in our lifetimes."

According to research cited in the report, in the next 90 years the acidity of the oceans could increase by up to 150 percent over per-industrial levels – a change that has not been seen for more than 50 million years.

Copyright 2012 Northwest Public Radio