Please note: You are viewing the unstyled version of this website. Either your browser does not support CSS (cascading style sheets) or it has been disabled. Skip navigation.

July 15, 2009

   Print Change text to small (default) Change text to medium Change text to large

Field observations during 2009 will be very limited because this is an "off year" for survey cruises in the GOMTOX program.  We are therefore piecing together an image of this unusual bloom from a combination of shellfish toxicity records from state monitoring programs and a few small vessel survey cruises. 

As 2009 began, our expectation was that we would have a "moderately large regional bloom"-  meaning that in the western Gulf of Maine, we would expect toxicity through most of western Maine, New Hampshire and portions of Massachusetts, possibly including part of Massachusetts Bay.  We envisioned a scenario similar to the 2006 year.  To view the April 22, 2009 news release regarding the 2009 bloom advisory, please click here. These advisories are considered most relevant to the western Gulf of Maine region as the dynamics of populations to the east remain poorly understood and modeled.

The bloom season began in a somewhat typical fashion, with shellfish toxicity being detected in western Maine and New Hampshire in early May (see PSP toxicity map).  In past years, where there has been significant toxicity in the western Gulf, this was a time when we also had at least one, and often two, major northeast storms that pushed Alexandrium cells to shore, rapidly increasing toxicity and propellig the bloom to the south as well.  Wind records for 2009 show a very weak northeaster in early May followed by a long interval with light and variable winds.  These conditions were nevertheless sufficient to cause toxicity and harvesting closures along most of western Maine, New Hampshire and Massachusetts (south to the middle of Massachusetts Bay - see map), but shellfish toxicities were low and survey cruises revealed very low cell abundances as well within that region. 

The bloom season seemed to be winding down in the western Gulf, with the reopening of closed areas in June, suggesting that the major input of cells was over. 

Typically, toxicity in eastern Maine increases in mid summer as those waters warm, and 2009 was no exception.  However, for reasons that remain obscure, the Alexandrium population "exploded" in the eastern Gulf causing rapid increases in toxicity in downeast Maine and extremely high levels of toxicity at some locations.  Volunteer citizen observers found large numbers of cells in their samples at many locations along the coast.  It would apear that the Alexandrium population thrived on the foggy and rainy conditions that persisted for most of the month of June. 

At this writing, we are concerned that the large populations from Maine are heading south, evidenced by the "red water" observed near Portsmouth, NH in a recent small vessel cruise (see photo) and also observed in a cruise near Cape Ann, MA (see map).  So while Massachusetts and New Hampshire watch closely for a resurence in toxicity (and Federal managers anxiously watch the situation in offshore, Federal waters) Maine is struggling with one of the worst red tides in its history.  This is best exemplified in the following text from Darcie Couture, Director, Biotoxin Monitoring, Maine Department of Marine Resources.
The 2009 paralytic shellfish poisoning (red tide) event in Maine, which flared up while the state shellfish beds were still under a series of late spring flood closures, is ongoing at this time, and does not show signs of ending as of yet.  Several benchmarks of this red tide event have already exceeded the record-setting red tide event in 2005:
1)       Dozens of PSP (red tide) sampling locations have exhibited record-high toxicity scores.  There are many places along the coast with scores exceeding 4,000 µg stx eq/100g, more than 50 times the federally mandated quarantine level of 80 µg stx eq/100g.
2)       The geographic extent of this red tide event is unprecedented, with many areas of the coast showing high levels of toxicity, areas where there has never been any toxin in the last 30 years of records kept by Maine DMR.
3)       The economic impact of this event is devastating.  Maine DMR estimates that there are 89,000 acres of productive shellfish in state waters, and at this time more than 97% of these resources are closed due to red tide.  In addition to the inshore shellfish resource, 100% of the off-shore Ocean Quahog resource beds are closed due to red tide.
4)       There have been unusual reports of mortality events in both short-nose sturgeon and eider ducks, which are currently suspected to be caused by the transfer of red tide toxicity through the food web to these larger animals.
As I mentioned above, there is no sign that this red tide event has reached an apex yet, while toxicity levels in eastern Maine are still rising, and the Maine shellfish industry will likely be facing several more weeks, if not months, of impact from this event.
So, in summary, 2009 has been a signficant year for a toxic Alexandrium red tide, particularly in Maine.  There are still many cells out in the water, and the potential for the situation to sustain itself, or even get worse. We will provide updates as they become available. 

Last updated: July 1, 2019

whoi logo

Copyright ©2007 Woods Hole Oceanographic Institution, All Rights Reserved, Privacy Policy.
Problems or questions about the site, please contact