Taylor Shellfish Hatchery
Dabob Bay, Hood Canal
Taylor changed their source of water to a deeper level
where typically lower pH (more acidic)
waters exist. How this helped is unclear.
Since March of this year the "Blue Ribbon Panel" has been meeting to determine what can be done to address CO2 and the lowering pH levels, with increasing focus on assistance for the shellfish industry. So much so that panel members have expressed varying concerns. Some are concerned of the perception that this significant effort in time and money is only for the benefit of the shellfish industry. Some question whether it is appropriate to focus on problems a non-native genetically modified (triploid) oyster has with lowering pH levels [click here for a study showing how different varieties of oyster have little trouble with lower pH levels]. Finally, some question whether the "alchametic" change in focus from CO2 to nitrogen is appropriate and whether deep sea upwellings will overwhelm any attempts made at the local level, whether it be CO2 or nitrogen. While these and other questions are appropriate, the evolving focus on whether local sources of nitrogen is the cause of lowering pH levels may be most appropriate.
There is no question CO2 is altering the world we live in. It can be clearly linked to rising temperatures and the lowering pH levels. Not so easily linked is how nitrogen decreases pH levels, and if it does, whether the local sources of nitrogen are even significant. The shellfish industry would certainly have us believe human activities along Puget Sound's shoreline are the primary source, perhaps best reflected in a sentence from an article by Jim Gibbons, owner of Seattle Shellfish: Excessive nutrients largely come from human activities that generate nitrogen, including broken or undersized septic systems, lawn fertilizers, storm water runoff, farm runoff, and pet wastes. (South Sound Green Pages, 2008) (Note: Jim Gibbons also testified before state legislators of his consideration to sue the state over "excess nitrogen.")
A matter of scale: Satellite image of the
annual algal bloom off Washington's coast.
Nutrient source: deep sea waters. When combined
with warming temperatures, large blooms result.
Algae is both a food source and absorbs CO2. Is that bad?
It appears, however, humans being the primary source of nitrogen in Puget Sound's Hood Canal is not the case. A September 14, 2012, report from the EPA and the Department of Ecology "...concluded that human sources of nitrogen contributing to low-oxygen events in the mainstem of Hood Canal were "insignificant," while evidence linking humans to oxygen problems in the more troubled area near the canal's end in Lynch Cove "is not strong."
"The overwhelming causes of fish kills, the agencies concluded, are the geography of the canal and ocean conditions." (Seattle Times, September 18, 2012)
There is little question the shellfish industry has both created the "Blue Ribbon Panel" and has moved the focus from CO2 emissions to nutrient reduction, specifically nitrogen. So doing now runs the risk of deflating the balloon which may have helped lift awareness of excess CO2 emissions and its impact. If it is perceived the majority of actions recommended only address the problems a non-native and genetically modified oyster is having in adapting to conditions which other shellfish are not having, an opportunity will have been lost, and a great deal of time and money will have been lost. The scientists and committee members are all intelligent enough to know you cannot turn lead into gold. It is unlikely CO2 can be turned into nitrogen.
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