Special Notice: VHS found in Lake Superior
A Cornell University research team’s recent finding of traces of the Viral Hemorrhagic Septicemia virus (VHS) in fish inhabiting Wisconsin and Michigan waters of Lake Superior is yet another reminder that anglers and boaters play an increasingly important role in preventing the spread of this fish virus and invasive exotic species.
Lake Superior is a potential gateway for VHS to enter Minnesota. Minnesota DNR has taken steps to prepare for this with changes in fisheries management activities, surveillance and legislation. With the possible entry of VHS into Minnesota waters of Lake Superior and other parts of the state, it is incumbent upon all users of the state's waters to remember to follow existing requirements:
- Remove all visible plants from your boat before leaving a water access;
- Drain water from your boat, motor, livewell, and bait containers;
- Dispose of unwanted bait in the trash; and
- Spray, rinse or dry boats and recreational equipment before transporting to another water body
Assuming all users of Lake Superior follow preventive measures as those listed above, no additional changes for recreational or commercial fishermen are likely at this time. However, smelt and baitfish like smelt taken from Lake Superior or its tributaries must be labeled as such and may not be used for bait in any other waters of the state.
Cause of disease:
Virus - extremely serious viral disease of fresh and saltwater fish
What does it look like?
At a low level of infection, fish might not display any symptoms. As the infection becomes greater, however, fish will display widespread hemorrhages (bleeding) throughout body surface (eye, skin and fins) and within the internal organs (swim bladder, intestine, kidney etc). Because of the bleeding, gills and liver might appear pale. Sick fish will often be listless, swim in circles, and are frequently observed at the surface of the water.
NOTE: Confirming VHS infection requires sophisticated laboratory testing. A diagnosis cannot be made based solely on observation because many different diseases of fish have very similar symptoms.
For more information, download the VHS flyer
Fish species affected:
To date, VHS has caused large-scale mortality in
- black crappie in Budd Lake (Michigan)
- bluegill in Budd Lake (Michigan)
- common carp in Lake Ontario
- freshwater drum in Lake Ontario, Lake Erie and Lake Winnebago (New York)
- gizzard shad in Lake St. Clair, St. Clair River and Lake Erie
- Great Lakes muskellunge in Lake St. Clair
- round gobyin Lake Ontario
- white bass in Lake Erie
- yellow perch in Lake Erie and Lake St. Clair
VHS has also been confirmed in smaller fish kills in
- black crappie
- lake whitefish
- rock bass
- smallmouth bass
Species known to carry VHS virus include (The disease has not killed any of these species to date.)
- channel catfish
- Chinook salmon
- emerald shiner
- lake trout
- northern pike
- rainbow trout/steelhead
- rock bass
- shorthead redhorse
- silver redhorse
- spottail shiner
- trout perch
- white sucker
How does the disease spread between waters?
- Moving infected fish from one body of water to another. This includes live gamefish caught in an infected water and live baitfish caught or used in an infected water and transported and used in another.
- Moving infected water and equipment from one waterbody to another. Examples would be the discharge of infected water and fish from ships, discharge of infected water from live wells on fishing boats, and discharge of infected bilge water from recreational and fishing boats.
- Stocking or releasing infected fish or water from infected fish hatcheries.
- The natural migration and movement of infected fish from one waterbody to another.
Where has the disease been found?
The disease has been found in Lake Huron, Lake St. Clair, Lake Erie, Lake Ontario, Lake Michigan, Lake Superior and the St. Lawrence River in New York. The virus has also been detected in several inland lakes including Budd Lake in Michigan and Lake Winnebago in Wisconsin. The Minnesota Department of Natural Resources is actively monitoring and testing for the VHS virus. So far the virus has not been detected in the inland waters of Minnesota.
If you would like to find out the most recent VHS infected sites call the DNR Pathology Lab at 651-259-5096.
Is it safe to eat?
The virus does not have any impact on humans, through direct contact or via fish consumption.
How can I prevent the spread?
Do not move live fish between waterbodies. DISPOSE of unwanted baitfish and fish parts in the trash.
Do not move any water between waterbodies. DRAIN water from boat, motor, bilge, livewells and bait containers before
leaving the water access.
SPRAY, DRY boat, trailer, and recreational equipment, especially after leaving known VHS infected waters.
- Power-wash boat hulls and gear with hot water (preferably 140 F)
- Rinse then dry the boat and gear completely for 12 hours.
If you catch a suspected diseased fish:
- Place the fish in a clean plastic bag and keep it in an iced cooler or refrigerator as quickly as possible (do not freeze).
- Call the local DNR fisheries office or the DNR Pathology Lab at 651-259-5096 right away for instructions.
- Do not risk spreading the VHS virus by bringing potentially diseased fish to DNR offices or hatcheries.
If you observe a fish kill:
- Call the State Duty Office (651-649-5451 or 1-800-422-0798) to report the waterbody, date, fish species, and number of dead or dying fish.
- Don't collect fish samples from a fish kill.