Toxic algae bloom prompts study

SEATTLE – Federal biologists have embarked on a research expedition to examine the largest toxic algae bloom along the West Coast in more than a decade, an occurrence that has prompted the closure of some shellfish harvests in Washington, Oregon and California.

The bloom involves some of the highest concentrations of the natural toxin domoic acid ever observed in some parts of the coast, the National Oceanic and Atmospheric Administration said Monday.

Local blooms of marine algae are common in spring, but the harmful algal bloom that began earlier this year has grown into the most severe in a more than a decade, the agency said. It stretches from Central California into Washington and possibly as far north as Alaska.