Categorizing the severity of paralytic shellfish poisoning outbreaks in the Gulf of Maine for forecasting and management.

Development of forecasting systems for harmful algal blooms (HABs) has been a long-standing research and management goal. Significant progress has been made in the Gulf of Maine, where seasonal bloom forecasts are now being issued annually using cyst abundance maps and a population dynamics model developed for that organism. Thus far, these forecasts have used terms such as "significant", "moderately large" or "moderate" to convey the extent of forecasted paralytic shellfish poisoning (PSP) outbreaks.

cysts in the Gulf of Maine: long-term time series of abundance and distribution, and linkages to past and future blooms.

Here we document cyst abundance and distribution patterns over nine years (1997 and 2004-2011) in the coastal waters of the Gulf of Maine (GOM) and identify linkages between those patterns and several metrics of the severity or magnitude of blooms occurring before and after each autumn cyst survey. We also explore the relative utility of two measures of cyst abundance and demonstrate that GOM cyst counts can be normalized to sediment volume, revealing meaningful patterns equivalent to those determined with dry weight normalization. Cyst concentrations were highly variable spatially.

Understanding interannual, decadal level variability in paralytic shellfish poisoning toxicity in the Gulf of Maine: the HAB Index.

A major goal in harmful algal bloom (HAB) research has been to identify mechanisms underlying interannual variability in bloom magnitude and impact. Here the focus is on variability in blooms and paralytic shellfish poisoning (PSP) toxicity in Maine, USA, over 34 years (1978 - 2011). The Maine coastline was divided into two regions -eastern and western Maine, and within those two regions, three measures of PSP toxicity (the percent of stations showing detectable toxicity over the year, the cumulative amount of toxicity per station measured in all shellfish (mussel) samples during that year, and the duration of measurable toxicity) were examined for each year in the time series.