Ocean acidification has arrived in Pacific Northwest
November 21st, 2011Massive die-offs of oyster larvae in the Pacific Northwest show ocean acidification from an excess of CO2 emissions has already begun.
In Netarts Bay, from 2006 to 2008, oyster larvae began dying dramatically. Elizabeth Grossman, in an article in Yale Environment 360, quotes Netarts Bay hatchery owner Mark Wiegard:
Historically we’ve had larvae mortalities [usually related to bacteria] . . . My wife sent a few samples in and Hales [Burke Hales, a biogeochemist and ocean ecologist at Oregon State University] said someone had screwed up the samples because the [dissolved CO2 gas] level was so ridiculously high.
Taylor Shellfish Hatchery in Washington, the country’s largest producer of farmed shellfish and one of the largest oyster producers, has also reported dramatic losses. Hood Canal has some of the Pacific Northwest’s highest levels of ocean acidification. Taylor’s hatchery there experienced the loss of about three-quarters of its oyster larvae, losses which are now being mitigated by buffering the high acidity.
Wild oyster beds in the Pacific Northwest are suffering, too. Wild oysters in Willapa Bay, Puget Sound, and off the east coast of Vancouver Island have seen reproductive failure because acidic waters have prevented oyster larvae from forming shells. Acidic water sometimes kills oyster larvae outright, so that they fail to survive past the egg stage. At other times the eggs hatch; but the larvae, stressed as they try to forms their first shells, fail after a week or two.
The water now washing ashore in Oregon and Washington actually absorbed its CO2 30 to 50 years ago. Oceans absorb about 50% of the CO2 released by burning fossil fuels. Since then, emissions have been rising even more dramatically.
Ocean acidity has increased approximately 30% since the Industrial Revolution and is on track to be 150% more acidic by the end of the century than it has been for 20 million years. Ocean acidification depletes seawater of the compounds that organisms need to build shells and skeletons, impairing the ability of corals, crabs, sea stars, sea urchins, plankton and other marine creatures to build the shells they need to survive. Ocean acidification could destroy all of the globe’s coral reefs by 2050 and threatens the entire marine ecosystem.
















