Fish kill problem continues to spread

A researcher said the fish seem to be dying of an infection that shouldn't be harming healthy fish.

Whatever it is, it seems to be spreading.

Since 2004, fish in the Shenandoah River have been dying, mottled with red and gray sores. Now the same symptoms are appearing among fish in the James, Cowpasture and Maury rivers in Western Virginia in counties that include Rockbridge and Botetourt.

"We've been dealing with dead fish, of course, and fish with lesions, up here in the Shenandoah for three years," said Don Kain, the water compliance and monitoring manager for the Virginia Department of Environmental Quality's Shenandoah Valley regional office. "This is kind of a surprise that it's moved into another watershed."

Kain, co-chairman of the task force charged with solving the problem, said the group was using the Cowpasture as a standard, healthy stream to compare with the Shenandoah. Now the problem has surfaced in the Cowpasture, too. So the Shenandoah River Fish Kill Task Force is expanding into the Cowpasture, James and Maury rivers, too.

The task force includes state and federal agencies, several universities, environmental and outdoors groups and citizens.

"We still don't know what type of problem we're dealing with," said Scott Smith, the Department of Game and Inland Fisheries biologist for the James.

Smallmouth bass began dying on the South Fork of the Shenandoah in 2004. It's happened every spring since. In 2005, up to 80 percent of the Shenandoah's smallmouths died. Sores and deaths have also turned up among redbreast sunfish, largemouth bass, rock bass and northern hogsuckers.

Reports started coming in from the James and Cowpasture rivers in May. The reports from the Maury, near Buena Vista, are the most recent.

"These are not your classic fish kill events," Kain said.

Classic kills wipe out fish, or particular species of fish, in a specific location in a limited amount of time. The kills that Kain is now investigating stretch over weeks and miles. Seemingly healthy fish continue to thrive among the ill and the dead. It is not clear how many fish have died in the kills over the past three years.

In a recent sampling trip on the James, fewer than half of the bass collected by Smith and Kain had lesions.

The researchers have also found male fish that have produced eggs.

"That problem's found all around the world," Smith said.

In the Potomac River in West Virginia and Maryland, researchers have found intersex fish and fish kills similar to those happening in Virginia.

But there's no clear connection, Smith said. It could be a coincidence, a cause or a symptom.

It's not even clear exactly what is creating the intersex fish. It could be hormones -- such as estrogen -- that get into the river through drugs in animal or human waste. It could be one of the thousands of chemicals capable of mimicking the effects of hormones. And it may not have anything to do with the fish kills at all.

"The most logical theory -- and it's still only a theory -- is that we're looking at something that's compromising the immune system in the fish," Smith said of the fish kill problem.

The fish seem to be dying of infections that shouldn't be a problem for healthy fish, he said.

"We're going through a process of elimination," Smith said of the search for the cause of the kills. "Every time we start to look real hard at one possible cause for the problem, we get a new data point that just blows that theory out of the water, and we have to start back as square one."

As far as researchers can tell, Smith and Kane said, it's as safe to eat the fish now as it was before the kills began. The Virginia Department of Health cautions people about eating too much fish from the James and Maury rivers because of PCB contamination. There's a fish consumption advisory on the Shenandoah because of PCBs and mercury.

Outdoors writer Mark Taylor contributed to this report.

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