ScienceDaily — A deadly fish virus that was first discovered in the Northeast in 2005 has been found for the first time in fish from Lake Superior, report Cornell researchers. That means that the virus has now been documented in all of the Great Lakes.
This walleye was infected with the viral hemorrhagic septicemia virus. Cornell researchers report that fish from Lake Superior have been found to be infected with the virus, which means that it has now spread to all of the Great Lakes. (Credit: Image courtesy of Cornell University)
The viral hemorrhagic septicemia virus (VHSV), which causes fatal anemia and hemorrhaging in many fish species, poses no threat to humans, said Paul Bowser, professor of aquatic animal medicine at Cornell's College of Veterinary Medicine.
Bowser and colleagues recently tested 874 fish from seven sites in Lake Superior in collaboration with the U.S. Geological Survey (USGS) Western Fisheries Research Center in Seattle. Fish from Paradise and Skanee in Michigan and St. Louis Bay and Superior Bay in Wisconsin tested positive. Some of the results have been corroborated by other laboratories; others have tests still under way.
The virus, which has been identified in 28 freshwater fish species in the Great Lakes watershed, has reached epidemic proportions in the Great Lakes and threatens New York's sport-fishing industry, said Bowser, estimated to contribute some $1.4 billion annually to New York's economy.
"People come from all over the eastern United States to fish the Great Lakes," said Bowser, noting that the virus has also been found in a few inland waters as well, including lakes, streams and a family-owned earthen pond. "The economy of many of these areas ebbs and flows with the season and perceived value of outdoor recreational opportunities. The value of these opportunities is dependent on how successful we are at managing the health of wild fish. On a worldwide basis, VHSV is considered one of the most serious pathogens of fish, because it kills so many fish, is not treatable and infects a broad range of fish species."