By early May, the distribution reached from the Lower Potomac and Patuxent Rivers, across the Bay and into the Choptank River on the Eastern Shore. Densities of Prorocentrum minimum were uniformly high throughout this area.

Nearing the end of May, the bloom has moved up the western shore into the Patapsco River area. The extent of the bloom has declined and high concentrations of Prorocentrum are more restricted to hot spots above the bay Bridge and at the mouth of the Potomac River.

Updates on this analysis of what conditions triggered and ended the bloom will continue throughout the summer as water quality data becomes available.  Please revisit the site on occasion for these updates.

See the blooms in Chesapeake Bay for the month of April.

For more information, please contact Peter Tango at (410) 260-8651.

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