Oysters in Distress

October 23rd, 2012

oyster-pic

There is something going on in the Oyster Beds of Puget Sound – and it isn’t good.  As this year’s oyster season commenced – the absence of mature oysters continues to alarm oyster farmers, retailers and restaurants.  The microscopic oyster larvae at hatcheries in Dabob Bay and other places in the Puget Sound were dying before they ever had a chance.  As the larvae developed tiny oyster shells, they began to crumble faster than they can grow.  This has been observed all over the northern Pacific coast and has been going on for years.  In fact, there has not been a viable larvae generation since 2005.

Scientists and farmers first looked into whether bacteria were causing the devastation.  But further investigation pointed to something much more serious and difficult to resolve: the undisputed increase in the CO2 levels in the atmosphere and the oceans.  One outcome noticeable to most has been the rising of the average temperatures here in the Puget Sound area.  This past July was the 36th consecutive July and 329th consecutive month in which global temperatures have been above the 20th century average. In addition, seven of the 10 hottest summers recorded in the United States have occurred since 2000.  While the arguments continue about the cause of global warming, the increase in CO2 levels has been well documented by the entire science community.  The scientific term is ocean acidification; as the CO2 level rises, the pH level falls.  A liquid’s pH measures the acidity or alkalinity on a 14 point scale – the lower the number, the more acidic the liquid.  Shellfish in particular have a narrow pH spectrum in which they can survive.  A normal sea water pH is 8.1 to 8.2 on the alkaline side.  On a sample day last spring, the pH level at 100 feet deep measured at 7.5, reflecting high acid levels, causing the inability of the larvae to maintain shell growth.

acidification-chart

A natural occurrence in the Pacific Ocean (but not found in the Atlantic) is upwelling.  As the north winds blow over the water, a circulation process is set in motion in which nutrients from the bottom of the ocean are pushed slowly upward.  Unfortunately along with nutrients the upwelling is carrying increasingly high CO2 levels.  This is a very long term problem, with no short-term solution in sight.  According to NOAA scientists, the water that is upwelling on our coast today is at least 50 years old.  CO2 levels have been increasing since the Industrial Revolution – about 250 years ago.  At that time the atmosphere’s carbon dioxide content was roughly 280 parts per million (ppm).  Today we measure in at about 390 ppm.  So even if we were able to drastically limit our CO2 output immediately, the problem is going to get much worse for a long time, before it starts getting better.  As part of the natural cycle of upwelling, it takes over 50 years for CO2 to go from the atmosphere to the ocean’s floor.  And because of Puget Sound’s unique geography – it is believed that the impact of increased acidity levels occurs here before the rest of the world.  So – it’s not just about the oysters.

upwelling-graphic

All of these issues are being examined by a blue ribbon panel convened last March by Gov. Chris Gregoire.  The panel is made up of scientists, local and tribal leaders and industry representatives.  Along with surveying the latest science and setting priorities for additional research and monitoring, the panel was tasked with creating a set of practical, affordable policy recommendations to address the root causes of acidification.  They also hope to come up with ways to help businesses and communities adapt.

During the coming year’s legislative session beginning in January, lawmakers will introduce a new bill in an effort to implement some of the action items that the panel believes need to be addressed.  The 28 member panel has come up with a 43 item list, 20 of which are deemed top priority measures.  Panel member Sen. Kevin Ranker (D-Orcas Island) has urged the panel to narrow down the list to its top 3 – 5 priorities.  According to Ranker, the potential top priorities should be:

  • Reducing air emissions that are linked to ocean acidity
  • Overhauling sewage treatment plans to reduce the amount of flow into local sea water (high nitrogen levels being another cause of acidification)
  • Exploring the idea of using salt water vegetation to combat the impact of ocean acidification
  • Improving and expanding the monitoring of ocean acidification

The state faces huge challenges.  State funding, regulation burdens for the business community and maintaining momentum over not just years – but decades might all seem to make this an insurmountable problem.  Adding to the pessimism is the fact that ocean water does not respond to state boundaries.  So we cannot solve this problem by ourselves.  Still – Washington is one of the first states to meaningfully address the challenges ahead.  Ranker has also made the very important point that the potential bill has both Democrat and Republican support and that both gubernatorial candidates have been kept in the loop on the findings of the panel and are on board to do what we can to address the issue.
For more information, see these websites:
University of Washington
BiologicalDiversity.org
Yale University

In the meantime we are hoping for cold winds and rain to cool off the oyster beds quickly so that we can get back to eating our favorite bi-valves.

This article was co-written by Elizabeth and Michael Fagin

Leave a Reply

RSS | XHTML | CSS