[Pharmwaste] A Mystery of Fish Mortality - Elusive Illness Plagues Some Virginia Rivers

DeBiasi,Deborah dldebiasi at deq.virginia.gov
Wed Jun 20 09:45:42 EDT 2007


A Mystery of Fish Mortality
Elusive Illness Plagues Some Virginia Rivers

By David A. Fahrenthold
Washington Post Staff Writer
Wednesday, June 20, 2007; B01

MORGAN FORD, Va. -- Something in the Shenandoah River is turning the
smallmouth bass thin and listless and causing sunfish to break out in
blisters that look like cigarette burns. Something in the water is
making both species weaken and die, leaving the river bottom flecked
with white bellies.

Something is doing all this. After five years of tests, more than
$600,000 in government money and uncounted numbers of dead fish, that's
still as much as anybody knows.

Since 2002, fish have been dying in the Shenandoah and other western
tributaries of the Potomac River, and scientists have been racing to
find the cause. They have considered viruses, oxygen-depleted "dead
zones" and runoff from chicken farms, but they have found nothing
definitive. At the same time, the search has been complicated by
die-offs this year in two rivers outside the Potomac watershed: the
Cowpasture and upper James.

At the center of the mystery is the Shenandoah, whose easy fishing and
picturesque setting have long attracted visitors from the Washington
area. Here, the impact has been ecological, economic and emotional, as
locals try to understand how this beloved waterway became something that
kills fish.

"It was such a beautiful river and everything," said Chuck Kraft, a
longtime fishing guide from Charlottesville, who has stopped bringing
clients to the Shenandoah. "It's kind of sad, you know. It's like losing
a friend or a family member."

This spring and summer, dead fish have been reported in six waterways
that begin in the mountains near the Virginia-West Virginia border. Four
are part of the Potomac River watershed: the North Fork of the
Shenandoah, the South Fork of the Shenandoah, the main body of the
Shenandoah and the South Branch of the Potomac. The other two are part
of the James River watershed.

Often, dead fish have large blisters on their sides or patches of fungus
that look like cotton balls. Sometimes, the gills are so inflamed that
they can no longer filter oxygen out of the water.

"You don't see a lot at one time, but you see some everywhere you look,"
said Bill Hayden, a spokesman for Virginia's Department of Environmental

The kills are not thought to signal a threat to human health. No risk is
seen to people who swim in the affected rivers or Washington area
residents whose drinking water is drawn from the Potomac downstream. But
it troubles scientists that the same types of fish, with the same
problems, have been dying in the region since 2002.

"We can't say it's the same thing," Hayden said. "But it is very

A 2002 fish kill occurred in the South Branch of the Potomac in West
Virginia. Beginning in 2004, die-offs followed in the Shenandoah and its
two main tributaries, which wiggle through mountain valleys just beyond
Washington's western suburbs.

In each case, scientists have looked for the usual suspects in any fish
kill -- a toxic algae bloom, a malfunctioning sewage treatment plant, an
overturned chemical truck -- and found none of them. Instead, some of
the fish were being killed by bacteria that they would normally be able
to fend off. Something, apparently, was weakening their immune defenses.

What that something is, though, remains elusive. In January, a report
from two university professors listed more than 20 theories that might
explain the problem. The suspected causes include a virus, pesticides
and the dumping of illegal drugs. None of the theories has been proved.

Vicki S. Blazer, a researcher with the U.S. Geological Survey, said a
major factor could be manure washed down from the chicken and cattle
farms that dot the Shenandoah Valley. Animal waste carries hormones,
such as estrogen, that can cause immune problems in fish.

"It overwhelms the fish, is my feeling. But we don't have any proof of
that yet," Blazer said.

One piece of evidence supporting this theory is the "intersex" fish
found in some of the same rivers: male bass are growing eggs, possibly
because of hormone-rich pollution.

A new wrinkle was added to the mystery this year when fish died in the
Cowpasture and upper James Rivers in far western Virginia. Both of those
waterways are unconnected to the others. For now, nobody can say whether
it is the same problem or, if it is, how it traveled overland.

The affected rivers seem significantly changed. Although some fish
species, including catfish and carp, have come through unharmed, others,
including smallmouth bass and redbreast sunfish, have been devastated.
After the 2006 fish kills, state scientists estimated that in sections
of the Shenandoah, 80 percent of the smallmouth bass had died.

"I think we're talking millions of fish," said Jeff Kelble, an
environmental advocate who is called the Shenandoah riverkeeper.

State officials said they have no way of estimating the total number of
fish killed

Even the bass that remain can seem weak and ill. One morning this week,
Kelble, a former Shenandoah fishing guide, launched an inflatable boat
here into a shallow, deep-green section of river. The scene was
pastoral: hayfields on the banks, mountains in the background and great
blue herons skimming the surface. But when Kelble reeled in a bass,
something was wrong.

"That fish should have a belly," Kelble said, but the stomach, which
should have been fat from spring feeding, seemed caved-in and gray. "You
see how that's concave? That fish should have a belly there."

Parasites or diseases might have taken advantage of the fish's poor
health, Kelble said.

The Shenandoah's famous bass fishery is not officially dead. The
president of a local chamber of commerce declared last week, "We are
open for business, and the fishing's good."

But the kills have made an economic dent. Last year, a James Madison
University researcher estimated that the gruesome kills had scared 2,100
fishermen from the Shenandoah area, at a cost of $686,000 to the local
economy and the state.

At Mossy Creek Fly Fishing in Harrisonburg, Va., Colby Trow said many
clients -- once drawn by the Shenandoah's famous bass -- had stopped

"They basically just said, 'We'll keep in touch, but we won't be back
until that river's clean,' " Trow said.

Instead of driving a few minutes to the South Fork of the Shenandoah,
Trow goes 120 miles each way to bring clients to a section of the James

Bob Cramer, a fishing guide in Dayton, Va., had been taking clients from
Northern Virginia out on the Shenandoah for $300 a day. Now he's helping
a friend install invisible pet-control fencing for $75 a day.

But Cramer said the loss was more than financial: It is a sin, he said,
that this rural stream seemed to be more toxic than big-city rivers.

"To me, it's just an embarrassment," Cramer said. "We live in such a
beautiful place, and we have such terrible water quality."

Deborah L. DeBiasi
Email:   dldebiasi at deq.virginia.gov
WEB site address:  www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
Mail:          P.O. Box 1105, Richmond, VA  23218 (NEW!)
Location:  629 E. Main Street, Richmond, VA  23219
PH:         804-698-4028
FAX:      804-698-4032

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