Ocean Acidification Process
Image: NOAA Pacific Marine Environmental Laboratory
Another day, another coal mine canary.
The Pacific Northwest is well-known for its oyster farms. I have friends who have been oyster farmers for years. I always think of oysters as being rough, thick-shelled, resistant creatures. Which they are, once they are mature. The ocean acidification process that has affected other calcifying species elsewhere in the world isn’t yet particularly dangerous for mature oysters.
What it affects in a dramatic manner are the oyster larvae. The rate at which their newly forming shells can take up enough calcium to protect them into maturity is outpaced by the rate at which the shells are dissolved by the amount of CO2 in the acidified seawater. Up to 80% of the oyster stocks have been lost over the past few years in some areas.
There are undoubtedly a number of different reasons for this kind of annual die-off. One stated cause is the geographic location of the Pacific Northwest, where long-term oceanic currents pull up water from deep sea depths, and corrosive waters that absorbed the massive carbon dioxide industrial emissions of the mid-twentieth century are spewed right into some of the world’s richest fisheries. Other possible causes – bacterial infections, pollution due to agricultural run-off, lack of sufficient amounts of phytoplankton, normal fluctuations in seawater quality, etc. – could likely also play a role.
The comment sections for the many articles on this topic are spiked with a large number of what look like well-informed contributions that dispute ocean acidification as the ‘real’ reason for this particular dramatic species decline, with arguments ranging from standard-issue climate change denial to frontal attacks on the researchers and journalists for not giving enough weight to whatever pet cause the commenter favors, be it pollution or bacteria or the sheer unknowability of specific life cycles in all their complexity.
Lively conversation and discussion are all fine and well, but – leaving aside the obvious cranks who just want the conversation to stop altogether – it is frustrating to see disputes that can be implemented and leveraged by those with an economic interest in fighting any changes that need to be made. It is frustrating to see these kind of arguments serve to confuse (or worse, bore) observers who are only marginally inclined to engage in the discussion in the first place, much less take action. It’s this kind of counter-productive discourse that leads to reactive rather than proactive policy-making.
Keeping in mind that if the acidified waters now upwelling in the Puget Sound and elsewhere along the coast are fifty years old, the next fifty years of industrially-impacted seawater is still yet to come. And the United States government states it is actually pleased with new signs that it will soon be the world’s leading oil supplier, not a promising course of development if what we need to do is reduce carbon emissions in the very country that is among the leaders in the reliance on carbon-based fuel.
Is this the only reason? Undoubtedly not. So what harm could it do to work on expanding phytoplankton populations, curbing agricultural run-off, and so on? As always, whatever the economic cost of immediate change might be, it won’t be any less if we wait.
Meanwhile, oyster farmers are doing what they can to save their $270 million/year industry. Reactive policy-making in some places means simply dumping large amounts of pH-balancing sodium bicarbonate into oyster beds in the hope that the oyster larvae will make it past the earliest phases and into adulthood.
More:
Trouble in the Water: Acidifying Oceans Hinder Health of Northewest Shellfish
