Despite recent reports of a good summer with few shellfish closures, recent biotoxin tests by the Maine Department of Marine Resources show reason for concern. Tests on blue mussels in Maine's Penobscot Bay showed the highest score "anywhere in several years" for the algal bloom Alexandrium fundyense, DMR reports.
According to Darcie Couture, DMR's director of biotoxin monitoring, signs indicate a significant concentration of red tide cells to the southwest of Penobscot Bay. Couture on Thursday predicted that red tide will sweep in and affect all of western Maine as soon as the next few days or weeks, depending on winds and currents.
"It has been a bit of a relief to have escaped the large-scale closures in western Maine so far this season, but I'm afraid we are definitely not out of the woods yet, and we may still see a 'typical' red tide season in that part of the state in the coming weeks and months," said Couture.
Red tide is caused by naturally occurring algal blooms that produce a toxin ingested by feeding shellfish. While harmless to bivalves like clams, mussels and oysters, high levels of red tide toxins can cause people who eat them to become sick or even die. Illnesses in humans are commonly referred to as paralytic shellfish poisoning, or PSP.
Red tide outbreaks have forced the closure of some New England shellfish beds to harvesting in recent years, causing a lapse in the region's clam, mussel and oyster supplies. Outbreaks in 2005 and 2008 were particularly harmful, resulting in extended closures from the Maine-Canada border to Martha's Vineyard off the coast of Massachusetts.
"In eastern Maine, the red tide season has a firm hold from Cutler to Canada, with scores still rising all over that area," continued Couture. The Canadian shellfish scores continue to rise as well, which tells me that the source for our eastern Maine problems is still strong and active."
DMR will be monitor the situation weekly throughout the summer, which Couture labeled as a "biologically active season."
