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Dead fish litter the beach underneath the Stratford Harbour cliffs. Officials from both Virginia and Maryland are investigating.
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By FRANK DELANO
Marine scientists in Maryland and Virginia are investigating a fish kill in the lower Potomac River where thousands of dead fish have washed up on Westmoreland County beaches between Colonial Beach and Coles Point.
"Environmental conditions in the river are definitely a major factor," said Julie Oberg of the Maryland Department of the Environment.
"There appears to be an extensive algae bloom that may be contributing to low dissolved-oxygen conditions in the river," she said.
Wilton "Tu" Parker of Montross said high tides Saturday and Sunday deposited thousands of dead fish on beaches beneath the Nomini Cliffs near Montross.
"I've never seen that many dead fish in my life," said Parker,
a 36-year-old Westmoreland County native. Parker said the dead fish included many species, including striped bass, croaker, perch, spot, shad and cow-nose sting rays.
"As far as I know, the kill stretches from Westmoreland State Park to, at least, the Lower Machodoc Creek. That's over 10 miles of river. Fish are dead in Nomini Creek all the way up to Prospect Bridge," Parker said.
Parker said many of the dead fish were large. "There were a few dead rock fish [striped bass] over 30 inches and lots of dead croaker up to 2 pounds," he said.
Over the weekend, the Virginia Department of Environmental Quality investigated one fish kill in Maddox Creek near Colonial Beach and another in Ames Creek, a tributary of Lower Machodoc Creek near Coles Point.
Both kills were minor, said DEQ Pollution Response Manager Mark Alling. He said he found about 30 small menhaden and white perch on the two beaches about 20 miles apart.
"If there is a harmful algae bloom going on, it would be highly unusual this early in the season," he said.
Alling said he had submitted water samples from the two creeks to laboratories at Old Dominion University and the Virginia Institute of Marine Science.
On June 1, a forecast of Chesapeake Bay ecological conditions suggested "a moderately high likelihood of harmful algal blooms in the tidal Potomac River this summer."
The blooms occur when high levels of nutrients wash into the river. The right combination of water temperature and salinity can cause alga populations to explode.
When the microscopic creatures die and decay, they use up much of the oxygen that fish need to live in the water.
Some algae can also produce toxins.
In February and March 2002, high concentrations of a toxic alga closed the Potomac's few remaining oyster beds for several weeks.
In June 2004, high concentrations of a blue-green toxic alga named Microcystis closed public beaches at Colonial Beach for several days.
If ingested in large amounts, Microcystis can cause illness in humans and death in pets or livestock, scientists say.
In issuing its summer forecast, Chesapeake Bay Program scientists predicted a Microcystis bloom in the Potomac beginning in early summer and lasting approximately one to two months.
Parker worried that a recent spill of raw sewage at Washington, D.C., may have caused the weekend fish kill 75 miles down the Potomac.
A power outage at the Blue Plains wastewater treatment plant May 19 caused the release of 17 million gallons of
untreated sewage into the river.
Conservation groups said the spill could cause significant fish kills, but the U.S. Environmental Protection Agency said the spill would likely have no long-lasting environmental impact.
MDE's Oberg said yesterday that her agency had just begun to investigate the Potomac fish kill and that it was too early to determine its causes.
To reach FRANK DELANO:
Email: fpdelano@gmail.com
