According to a seafloor survey conducted in the fall of 2007 by Andersons team, the number of Alexandrium cyststhe dormant, seed-like stage of the algaes life-cycleis more than 30 percent higher than what was observed in the sediments prior to the historic bloom of 2005. The seed beds were especially rich in mid-coast Maine, origin of many of the cells that affect western Maine, New Hampshire, and Massachusetts.
Other environmental factors then determine the extent to which the blooms spread down the New England coast. Much of the Northeastern United States was hit with record- or above-average rain and snowfall this winter, which will provide an extra pulse of fresh water and nutrients into coastal waters this spring. The blend of nutrients and fresh water into salty sea water can improve growing conditions for the algae.
Our hypothesis is that cyst abundance and the weather determines the bloom season, said McGillicuddy, a biological oceanographer in the WHOI Department of Applied Ocean Physics and Engineering. Will the conditions this spring lead to an extensive bloom along the New England coast" The wind patterns of the next few weeks will determine that.
The research team has run its computer model through four scenarios, using the predominant wind patterns from each year since 2004. Toxicity levels during those years have ranged from little to nothing in the western Gulf of Maine (2004 and 2007), to extremely high levels (2005 and 2006). Blooms were worst for scenarios in which the spring weather was dominated by strong northeast winds, which tend to drive Alexandrium cells toward the sout
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| Contact: Mike Carlowicz mcarlowicz@whoi.edu 508-289-3340 Woods Hole Oceanographic Institution Source:Eurekalert |