'Red tide' possible in U.S. northeast

WOODS HOLE, Mass., April 22 (UPI) -- U.S. scientists say there's a "moderately large" chance for outbreaks of the phenomenon called "red tide" in the Gulf of Maine area this spring and summer.

Researchers at the Woods Hole Oceanographic Institution and North Carolina State University said their prediction is based in part on a seafloor survey of quantities of Alexandrium fundyense -- the algae toxin that accumulates in clams, mussels, and other shellfish and can cause paralytic shellfish poisoning in humans.

The researchers said they found concentrations of Alexandrium cysts -- the dormant seed-like stage of the algae's life cycle -- in the Gulf of Maine to be 40 percent lower than the historically high levels observed prior to last year's bloom, but still higher than the level preceding a major regional bloom in the spring 2006 that closed shellfish beds from Canada to Massachusetts Bay.

"Last year at this time, we issued an advisory for a very large regional bloom that did in fact occur. In hindsight, that advisory was 'easy' because the cyst concentrations were higher than we had ever seen …" said WHOI senior scientist Don Anderson. "It's more difficult to make a prediction this year because the numbers of cysts we found are not extreme."

The research was supported by the National Oceanic and Atmospheric Administration, the National Institutes of Health and the National Science Foundation.