Ocean Acidification Hits Northwest Oyster Farms

April 22, 2010 — -- Mark Wiegardt and Sue Cudd have each dedicated about 30 years of their lives to bringing oysters to our tables. Now the two have found themselves in the forefront of one of the newest, most pressing environmental issues of our time: ocean acidification.

It all began with the oyster larvae at their Whiskey Creek Shellfish Hatchery in Tilamook, Ore.

"It first started in 2007. We had a situation here when all of a sudden, our larvae started dying," said Wiegardt.

"At first we started wondering, what is wrong? Bacterial problems? What are we doing wrong?" Cudd said.

Desperate, Wiegardt and Cudd turned to expert oceanographer Burke Hales and his team from Oregon State University to study the new and alarming enigma. They learned that the Pacific waters piped into their hatchery from nearby Netarts Bay were the cause of the dying larvae.

Whiskey Creek's 8,000 gallon water tanks take in water from the Pacific Ocean and Netarts Bay. The water used in the hatchery is rough-filtered and heated, and pumped into the tanks that house roughly 48 million swimming larvae. If the larvae stop swimming, that's a problem.

The scientists went to work and learned that something was making the oceans too acidic and preventing the oyster larvae from growing shells. No shells means certain death.

When winds blew the ocean's deep carbon-rich waters onto the surface, hatcheries up and down the Northwest Pacific Coast began to suffer the same fate as Whiskey Creek.

"The chemistry is very simple. It is 101. Carbon dioxide makes the water more acidic, that is irrefutable," said Burke Hales, Oregon State University professor of oceanography.Oceans act as sponges. According to the Natural Resources Defense Council, the oceans soak up one-quarter to one-third of all CO2 from fossil fuels. About 500 billion tons have been absorbed by the seas. Close to 22 million tons of C02 a day mix with the natural carbon of the ocean. But too much carbon and water makes the ocean too acidic.

Plants need carbon to grow, and animals exhale it with every breath. But too much carbon creates a problem. Where will it be stored, and how will it affect the chemistry of the planet?