WASHINGTON (Reuter) - Pfiesteria, the fish-eating bug plaguing
fishermen and health officials along the East coast, has been
around for thousands of years, the U.S. Geological Survey said
Wednesday.
It said core samples taken from the sea floor showed
organisms that look like Pfiesteria were present as long as 3,000
years ago.
"Sediment cores taken from the bottom of the
(Chesapeake) Bay and its tributaries allow scientists to look
into the past by analyzing fossil pollen, algae, protists, molluscs,
crustacea and fish from as long ago as 3,000 years," the
USGS said in a statement.
Geologist Thomas Cronin said scientists processed
the mud from the Bay in the laboratory, examined the organisms
through different microscopes, and studied the chemistry of shells.
``For the moment, we have only gone back about 3,000
years but we would expect to get similar results from sediment
that goes back even further,'' he said.
USGS said it was working with experts to try to find
out the origin of the organism, blamed for killing billions of
fish in recent years.
Pfiesteria is a dinoflagellate -- neither plant nor
animal, it is in the same kingdom as slime molds. It swims with
two tiny tails and releases toxins that seem to first stun and
then dissolve the flesh of fish.
Pfiesteria is also blamed for causing a rash of health
problems in some people, from skin irritation to memory loss.
Experts say runoff of fertilizers and pollution into the waterways may be causing ``blooms'' of the algae.