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March 28, 2008
Richmond, Virginia — The Department of Environmental
Quality and the Department of Game and Inland Fisheries are
directing numerous scientific studies and surveillance programs
this spring in the western portion of Virginia in preparation for
potential fish kills.
Unexplained fish kills and episodes of fish with sores and lesions
have occurred during each of the last four springs in the
Shenandoah River system. In 2007, similar events also occurred in
the upper James and Cowpasture rivers.
The fish kills since 2004 have been unusual, affecting mainly
adult smallmouth bass and sunfish. Slow fish die-offs have begun
in early April and continued through May. Despite the efforts of
many fish health and water chemistry experts, the causes of the
fish kills remain unknown.
Studies by state and federal scientists and several university
researchers during these fish kills have focused on water
chemistry and the health of fish and other aquatic life. Water
quality studies to date have targeted nutrients, ammonia and
selected organic compounds, but they have not identified any
specific chemicals at levels that would be expected to cause the
fish kills.
Fish health findings suggest that multiple stressors may be
involved, because the symptoms do not clearly indicate any single
cause. Fish health and disease experts with the U.S. Geological
Survey, the U.S. Fish and Wildlife Service, Cornell University and
Virginia Tech have found gill, liver and kidney damage; large
numbers of parasites; and signs of bacterial infection. Viral
studies have ruled out the likely fish viruses. More detailed
investigations focusing on biological sources of disease are
planned for 2008.
Since 2004, state agencies and their partners have led multiple
investigations into these fish kills. In 2005, DEQ and DGIF formed
the Shenandoah River Fish Kill Task Force, an open group of
stakeholders, including university and government scientists,
environmental groups, fishing guides, and volunteer monitors. This
group identified a list of theories on possible causes of the fish
kills and methodically reviewed studies to test those theories.
In 2007, DEQ contracted with fisheries experts Dr. Greg Garman of
Virginia Commonwealth University and Dr. Don Orth of Virginia Tech
to lead a research advisory committee of experts in chemistry,
water quality, toxicology, soils science and agriculture. The
committee is an independent advisory panel to DEQ and has recently
completed a recommended work plan for 2008.
Based on recommendation from the committee and the Fish Kill Task
Force, DEQ and DGIF have set priorities for available funds and
are coordinating a number of investigations. Studies in 2008 will
emphasize additional non-fish kill sites, expanded water quality
chemical lists with a focus on storm flows, and multiple fish
health investigations.
Scheduled projects and lead investigators include:
* Expanded fish health study to evaluate organs, blood chemistry,
parasites and tissue contaminants — Virginia Tech and USGS.
* Watershed and fish kill contaminant profile — Virginia Institute
of Marine Science.
* Measuring pesticides, organic compounds and heavy metals in
storm runoff — James Madison University.
* Measuring organic compounds in the river during the spring using
passive samplers, devices which allow measurement of chemicals
that are normally not detectable using conventional methods - DEQ
and USGS.
* Biweekly analysis of heavy metal concentrations in the rivers
during the spring — DEQ.
* Fish kill and fish behavior surveillance by volunteer citizen
monitors — task force, state agencies and citizens.
* DEQ and DGIF investigators also are participating in a
coordinated study with USGS, the U.S. Environmental Protection
Agency, and the West Virginia Department of Environmental
Protection on additional fish health studies at several sites
within the Potomac River watershed.
If any fish kills are observed this year, the task force
encourages the public to provide information on the location,
number and type of fish found dead or sick in the Shenandoah,
Cowpasture and James river systems. Distressed fish are found
mainly in eddies and shallow areas away from the main current.
Anyone with information is asked to call the DEQ regional office
in Harrisonburg at (540) 574-7800, or toll-free in Virginia at
1-800-592-5482.
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