Scientists from a NOAA-funded project in the Gulf of Maine issued an outlook for a moderate season of toxic algae blooms known as "red tides" in the spring and summer of this year, indicating some risk to the New England shellfish industry.

When the algae drift into commercial beds, state agencies shutter them for consumer safety, a financial hardship for communities whose livelihoods depend on the industry. For example, a 2005 Alexandrium bloom cost Massachusetts nearly $50 million and Maine about $23 million.

A survey cruise last year encountered a modest amount of cysts compared to past years, leading researchers to believe this year's season could be similar to the levels experienced during 2006 and 2007, when toxicity affected much of the Maine and New Hampshire coasts, but there were few closures in Massachusetts. The number of cysts on the ocean floor is an indicator of the following year's bloom severity.

This Woods Hole Oceanographic Institution project was funded by the National Centers for Coastal Ocean Science.

Seasonal outlooks for the Gulf of Maine have been issued annually since 2008. They are part of a NOAA effort to develop a HAB Operational Forecasting System that will provide HAB forecasts similar to routine weather forecasts. The Gulf of Maine is one of several regions for which HAB forecasts are being developed with the intent to operationalize them within NOAA, utilizing multiple assets such as those provided by the National Weather Service.

The PCMHAB project, under the leadership of Dr. Dennis McGillicuddy of Woods Hole Oceanographic Institution, issued the forecast based on an Alexandrium cyst survey map measured the previous autumn (cysts are bottom-dwelling, dormant, resting cells that germinate under favorable oceanographic conditions). The outlook derives from computer model simulations using the cyst map, weather, and oceanographic data from this and past years.

Scientists cannot make a precise "forecast" of where and when the bloom will end up because bloom transport depends on weather events that cannot be predicted months in advance. More precise weekly forecasts are provided to managers while blooms are ongoing.

Learn more about the forecast and the model: NOAA HAB Operational Forecasting.