Ocean Acidification

Puget Sound Restoration Fund has teamed up with a suite of partners to investigate one of the marine environment’s latest emerging issues – ocean acidification. Ocean acidification is an on-going process in which the seawater of the world’s oceans is becoming more acidic, and this process may have drastic impacts on many of the organisms that live in the sea. PSRF and its new team of partners aim to examine what may be the impacts of ocean acidification on Olympia and Pacific oyster populations within Puget Sound.

Carbon dioxide in the atmosphere is constantly reacting with seawater; it always has. But as the amount of carbon dioxide in the atmosphere increases the chemistry of the world’s oceans is changing and the seas are becoming more acidic.

So what’s the big deal? Oysters and other shellfish, like many organisms in the ocean (eg., abalone, corals, foraminifera), rely on hard shells or skeletons. These shells are made of calcium carbonate (the same compound as chalk), a compound that they form by using ingredients from the seawater. As the pH of seawater drops, the ingredients that are necessary for the formation of shells may become less available and it may affect the development and, ultimately, the survival of these marine organisms.

Anecdotal evidence and early data have shown a correlation between declining oyster recruitment and lower pH in nearby Willapa Bay, but the jury is still out as to what the relationship between these phenomena really is. To better understand similar changes to the environment of Puget Sound, PSRF, the University of Washington, NOAA , Puget Sound Partnership, Washington Department of Ecology, Pacific Shellfish Institute, Pacific Coast Shellfish Growers Association, Taylor Shellfish and Baywater, Inc. are working together to carefully monitor how a changing physical environment may affect the settlement and survival of Olympia and Pacific oysters in Puget Sound. The project is being funded by the Puget Sound Partnership.

Beginning in summer 2009, water samples are being collected in Totten Inlet and Dabob Bay (Hood Canal) to examine water quality, oyster larvae and phytoplankton communities. These samples are then complemented by a suite of water measurements (temperature, salinity, oxygen, chlorophyll, nitrate, and currents) and meteorological data (eg., carbon dioxide levels). The group of collaborators will continue to collect and process data in order to identify any emerging trends that may help us to predict the ecological and economic effects that ocean acidification may have on this crucial component of Puget Sound.