Tracking Harmful Algal Blooms

In a harmful algal bloom (HAB) a profusion of a harmful species of algae at the coastline causes toxins to accumulate in filter-feeding shellfish, such as mussels, clams, oysters and scallops. Humans can become sick from eating toxic shellfish; affected beaches may be closed. The incidence and persistence of individual HAB events are increasing.

Monitoring programs exist but generally are able only to detect an event after it has impacted coastal communities. Scientists are working to identify conditions favorable to blooms of toxic species so they can pinpoint where to look and to define the unique optical signatures of major harmful species so they can identify and track blooms.

Pete Strutton of COAS is working with Michelle Wood, a biologist with the University of Oregon, to study HABs in the highly productive area off the Oregon coast. Strutton and Wood will analyze a decade of data on sea surface temperature, ocean color and concentrations of domoic acid concentrations of coastal Oregon, looking for satellite-based physical and optical signals that indicate HABs. They will collect data over Heceta Bank southwest of Newport, a possible “incubator region” of the toxic species, and test the ability to target HAB water masses based on satellite signals.

The researchers also will work with NOAA CoastWatch to develop satellite products that can be disseminated to the scientific and coastal management community. Ultimately, such products could serve as an early-warning system for coastal managers, health officials and commercial and recreational fishers.

For more information:

• National Ocean Service: Harmful algal blooms
  
  
• SeaWeb ocean briefing: Harmful Algal Blooms and Toxins
  
  
• Los Angeles Times in-depth articles
  • Sentinels Under Attack (effect on marine mammals). 7/31/06
  • Dark Tides, Ill Winds (effect on humans). 8/1/06
    

CIOSS scientists track harmful algal blooms (HAB), which cause toxins to accumulate in filter-feeding shellfish such as mussels.