A sample collected near the mouth of Battle Creek, a tributary to the Patuxent River, on Sunday June 29th showed significant bloom densities of Karlodinium micrum at 144,000 cells/ml. The region is approximately 8 miles upstream of St. Leonard's Creek, which has been experiencing a "Black Tide" that is recently showing densities only 1/3 of the Battle Creek concentrations, but still only about 10% of the peak bloom observed on June 18th on St. Leonard Creek (see HAB News from June 24, 2003: "Black Tide on St. Leonards Creek, Calvert County.").