Miller and his team found that Eastern oysters experienced a 16 percent decrease in shell area and a 42 percent reduction in calcium content when specimens in the pre-industrial CO2 treatment were compared with those exposed to the levels predicted for the year 2100. Surprisingly, the closely related Suminoe oysters from Asia showed no change to either growth or calcification.
The results reported suggest that the impacts of acidification may be tied to a species' unique evolutionary history and environmental setting, implying that predictions may be more complex than previously thought. "In the Chesapeake Bay, oysters are barely holding on, where disease and overfishing have nearly wiped them out. Whether acidification will push Eastern oysters, and the many species that depend on them, beyond a critical tipping point remains to be seen" said Miller.
With numbers so critically lowthe oyster population in the Chesapeake Bay today stands at just 2 percent of what it was in colonial timesfuture losses could have dire consequences, both environmentally and economically. Indeed, the recently enacted Federal Ocean Acidification Research and Monitoring Act of 2009 recognizes the urgent need to begin addressing impacts of acidification on estuaries and their biota.
With the continued burning of fossil fuels, further acidification is unavoidable. Miller's team is keenly interested in what the biological and ecological responses will be in order to better inform current and future environmental restoration efforts. "In a high
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