Delaware officials said yesterday that tests of water samples from the Indian River in early August verified the presence of Pfiesteria piscicida in a nontoxic form. The river will remain open, they said.
Researchers say Pfiesteria can take numerous forms, several of them toxic, but also can remain dormant and harmless for long periods. The state's Department of Natural Resources began investigating after several reports of fish with lesions. There have been no reports in Delaware of fish kills related to Pfiesteria or of human health complaints such as those experienced by several people in Maryland, said a department spokesman.
"The fact that it's present is of concern," said spokesman David Small. "We haven't seen anything suggesting Pfiesteria being active, based on what we've seen in the Pocomoke."
The microorganism did not show up in other water samples taken at the same time from Indian River Bay.
However, Pfiesteria has become the chief suspect in a 1987 kill that left about 100,000 fish dead in the Indian River near the community of Oak Orchard.
The connection to Pfiesteria was made last week after tests on 10-year-old water samples indicated that the microbe, or one like it, was present in the water.
Pub Date: 9/24/97