The La Crosse Fish Health Center completed another successful year of the Wild Fish Health Survey.  To date, this was the most active year of the survey.  The fish health center has taken health samples from almost 7,300 fish representing 40 species.

Since 1997, 27,000 fish have been sampled; almost 30% of this total was completed in 2007.  The increased sampling is in response to Viral Hemorrhagic Septicemia (VHS).  The virus appeared in the Great Lakes in 2003, but it wasn’t until 2005 that massive fish kills occurred. 

The virus causes hemorrhaging in the fish’s organs and externally in the eyes, skin, and fins. At this time, VHS has been isolated from 25 different species in Region 3.  Along with this virus the fish health center also screens for nine other viruses, 5 types of bacteria, and two specific parasites.

 The survey covered a good portion of region 3.  It had a strong emphasis on the Great Lakes and the Mississippi River.  A large number of fish were tested from Lake Erie, Lake Huron, Lake Michigan, and Lake Superior. 

There were also water supply streams tested from many federal and state fish hatcheries.  Checking for harmful fish pathogens in these water supplies is important to protect the valuable fish in our hatchery system.  To cover  Region 3 a large amount of partner participation is needed for fish collection. 

The success of the Wild Fish Health Survey is made possible from help from our National Fish and Wildlife Conservation Offices, National Fish Hatcheries, State conservation groups, tribal agencies, and USGS. 

 There were some interesting findings that came out of the 2007 wild fish health survey.  On an encouraging note VHS  may  not have made its way into Lake Superior, as all 478 of the fish sampled  came back negative. 

The fish health center isolated the virus from Lake Erie, Lake Michigan, and Lake Winnebago showing new sites where the virus is found.  Another virus of concern was isolated out of the Mississippi River.  The virus of concern is called Spring Viremia of Carp (SVCV).  SVCV is an exotic virus historically found in Europe and Asia. 

In 2002 the virus was isolated from a Koi farm in South Carolina and in a Lake in Northern Wisconsin.  This was the first time the virus was found to be active on the Mississippi River.  It is not yet known how the virus affects our native species.