- The Washington Times - Monday, September 16, 2002

BOWLEYS QUARTERS, Md. The white perch and pumpkinseed pulled from a state biologist's net a few days ago in a tributary of the Middle River looked healthy.
But the fish Rob Magnien observed here three years ago had serious problems. A pfiesteria outbreak caused hundreds of menhaden a small bait fish that swims in large schools to break out in ugly open lesions, in some cases so large that the fishes' guts hung out of their bodies.
"It would just turn your stomach," said Mr. Magnien, the Department of Natural Resources' director of tidewater ecosystem assessment. "You wouldn't believe the fish were still alive."
The discovery on this heavily populated Baltimore County waterway came two years after a toxic outbreak of the micro-organism on the lower Eastern Shore that caused more than a dozen people to get sick.
State officials monitored the Middle River almost every day to see if the pfiesteria turned toxic there, finally concluding that it did not.
In many ways, the effort to nail down what microscopic organisms are in Maryland's waterways and what it means to the people and wildlife that use them has not stopped since. DNR teams monitor the water from April to October at about 70 sites on the Chesapeake Bay and its tributaries, as well as a few places in the coastal bays.
A rapid response center was established on the Nanticoke River in Dorchester County for collecting and processing water samples when there's a fish kill. Other permanent monitoring stations are moored to docks. The DNR set up a Web site last week where Marylanders can check water conditions across the state.
Pfiesteria's still widely detected, though not in its toxic form. Still, nontoxic pfiesteria can attack and feed on fish, scraping open a wound that is exacerbated when fungus infects it, causing big, bloody lesions. In the Middle River in 1999, the pfiesteria population "got so large that it seeded the entire river," Mr. Magnien said.
Since then, pfiesteria has lingered there, though water samples indicate its presence has trailed off from about 50 percent last year to 20 percent this year. That decrease pleased DNR biologists because drought conditions this year are similar to those in 1997 and 1999.
However, August through October marks the peak season for pfiesteria, and DNR biologists note pfiesteria levels increased last week on the Middle and Chicamicomico rivers. Significant numbers of menhaden turned up with lesions the first such instances this season.
Outbreaks such as those in the late 1990s were a symptom of a larger, ongoing problem that could cause future blooms of toxic pfiesteria and other harmful microbes, Mr. Magnien said.
Scientists largely attribute the proliferation of algae in Maryland's waterways to an overabundance of nutrients such as nitrogen and phosphorus that are introduced by sources ranging from sewage to coal burning industries in the Midwest.
Nutrients in Middle River are largely attributed to residential and industrial wastewater. On the Eastern Shore, runoff of chicken manure from poultry farms and fertilizers used for agriculture has been widely blamed.
Even nontoxic algae can devastate the ecosystem. When it grows out of control, it blacks out the light so that underwater bay grasses which provide crucial habitat for everything from blue crabs to small fish can't grow.
Also, algae tends to grow in boom-and-bust cycles. When masses of algae die at once, it consumes oxygen in the water, suffocating fish. Large fish kills are often the product of an algae bloom that crashes.
"We need to address the nutrient problem, not just because of pfiesteria but for the overall health of the system," said Theresa Pierno, Maryland executive director of the Chesapeake Bay Foundation.
First discovered in 1988, pfiesteria is a natural part of the marine environment that is believed to have a highly complicated lifecycle with 24 reported forms, a few of which can produce toxins. Pfiesteria is a form of dinoflagellate, a microscopic, free-swimming, single-celled organism that's usually classified as a type of algae.
There's still a lot that is unknown about pfiesteria, including what weather conditions help it thrive, whether it morphs into a toxic state and why, and how exactly it can affect humans. Medical evidence collected in 1997 suggests that exposure to an outbreak of pfiesteria may cause short-term memory difficulties and respiratory problems.
Still, Mr. Magnien says there are species out there that may be just as damaging.
"It seems that every year another species or two comes to light," Mr. Magnien said.

Sign up for Daily Newsletters

Copyright © 2019 The Washington Times, LLC. Click here for reprint permission.

The Washington Times Comment Policy

The Washington Times welcomes your comments on Spot.im, our third-party provider. Please read our Comment Policy before commenting.


Click to Read More and View Comments

Click to Hide