Fibrocapsa japonica

Fibrocapsa japonica was collected in low to moderate densities during June 2002 from the Coastal Bays St. Martin River. Fibrocapsa belongs to a group of plankton known as the Raphidophytes; small, flagellated golden-brown cells. There are only about a dozen known species of Raphidophytes in the world but about half are known to be harmful to marine life (Hargraves and Maranda 2002). Fibrocapsa has had devastating impacts on mariculture operations in Japan. Strains of Fibrocapsa japonica collected from the North Sea in Europe have been capable of producing toxin that killed fish in laboratory tank studies. Two seals that died in the Wadden Sea of Germany were shown to have high levels of the toxin Fibrocapsin. Conditions for bloom formation and toxin production are not well known. No evidence of toxicity has been detected in samples of Fibrocapsa taken from Maryland waters. Other Raphidophytes of concern that have been found in the Chesapeake and Coastal Bays during water quality monitoring by Maryland Department of Natural Resources are Heterosigma akashiwo and species of Chattonella.