The toxic microbes such as pfiesteria feed on algae as well as fish. Last year an outbreak of pfiesteria on two tributaries of the Chesapeake Bay attracted national attention, forcing the closing of the two rivers and killing thousands of fish. At least 39 people suffered health effects from skin rashes to memory loss, according to federal officials. Suzanne Schwartz, director of oceans and coastal protection at the Environmental Protection Agency, said the agency is working with states to develop rapid response plans in case of outbreaks this summer. Federal agencies and scientists have stepped up research into the cause of pfiesteria and are trying to find ways to more quickly detect it in rivers and streams.
Many scientists believe it is linked to nutrient runoff including wastes from poultry farms.
But Garcia and a panel of scientists, who also testified, emphasized that pfiesteria is only one of many toxic plankton that threaten waterways, and that an even broader problem involves the large concentrations of harmful algae blooms that deprive water of oxygen and create vast dead zones devoid of fish. One such area is off Louisiana in the Gulf of Mexico. The large algae concentration, covering 7,000 square miles, comes from nutrients washed down the Mississippi River including fertilizer and animal waste from Midwest farms. But Dr. Nancy Rabalais of the Louisiana Universities Marine Consortium, who has studied the Gulf bloom extensively, says the problem is national. D-La., are pushing legislation that would provide more money for research into harmful algae blooms and toxic microbes that threaten coastal fishing areas.