Clark Lake and Tributaries Now VHS Positive! Deadly Fish Virus Threatening Wisconsin’s Fish

Posted on 01. May, 2009 by in Invasives

VHS waters extended as two dams fail to stop fish

VHS

VHS

Viral Hemorrhagic Septicemia (VHS) is a deadly fish virus and an invasive species that is threatening Wisconsin’s fish. VHS was diagnosed for the first time ever in the Great Lakes as the cause of large fish kills in lakes Huron, St. Clair, Erie, Ontario, and the St. Lawrence River in 2005 and 2006. Thousands of muskies, walleye, lake whitefish, freshwater drum, yellow perch, gizzard shad, redhorse and round gobies died. Many Chinook salmon, white bass, emerald shiners, smallmouth bass, bluegill, black crappie, burbot, and northern pike were diseased but did not die in large numbers.

The hundreds of thousands of anglers expected to fish the May 2 opening day of the inland fishing season can help protect their fishing future by taking steps to avoid accidentally spreading VHS fish disease and aquatic invasive species.

“It’s important to take steps to prevent VHS from spreading every time you’re on the water, but particularly now when the disease is most active with the cold water temperatures,” says Karl Scheidegger, the Department of Natural Resources fish biologist who leads DNR’s fisheries outreach efforts. “Anglers did a great job last year in taking precautions, and with your help again this year, we think we can continue to contain the disease.”

VHS fish disease is not a human health threat but can kill 37 different species of fish, including trout, musky, bass and bluegill, and it caused large fish kills in some Great Lakes waters in 2005 and 2006. The disease was first detected in Wisconsin in 2007 in fish from the Lake Winnebago system and the Lake Michigan system; tests since then suggest the disease hasn’t spread beyond those waters.

“Anglers inadvertently moving infected live bait is a main way that VHS fish disease can spread to new waters; and with more than 400,000 fishing licenses sold by mid-week, the risk of spreading the disease is real,” Scheidegger says.

Anglers leaving boat launches with Eurasian water-milfoil and other plants attached to their boats or trailers, or juvenile zebra mussels in bilge water and live wells, also are at risk of spreading these and other invasive species to new waters. These and other invaders can take a toll on fish and fishing.

“Many of the same steps that will prevent the spread of VHS also prevent the spread of these invaders,” Scheidegger says. Those steps are:

  • Inspect boats, trailers and equipment and remove visible aquatic plants, animals and mud before leaving the water access.
  • Drain water from your boat, motor, bilge, life wells and bait containers before leaving the water access.
  • Don’t move live fish away from a waterbody. Buy minnows from a Wisconsin bait dealer and use leftover minnows on another water only if you have not added to the bait container fish or lake or river water.

VHS rules and more information on the fish disease is found online at VHS and You: Keeping Wisconsin’s Waters Healthy; lists and maps showing which waters have zebra mussels and other aquatic invasive species are found online at Aquatic Invasive Species Lists and Maps.

Longer stretches of the East Twin River and its tributaries in Manitowoc and Kewaunee counties, and Clark Lake, Logan Creek and Lost Lake in Door County are now considered to have VHS fish disease present and, therefore, have restrictions on bait harvest.

The extension of VHS-positive status to these waters reflects only a determination that low head dams on these waters are not preventing fish from Lake Michigan from reaching them. Fish from these waters have not so far tested positive for VHS.

DNR fish crews netting Clark Lake in Door County earlier this spring found fresh run steelhead, indicating that the low head dam on that lake is not an effective barrier for steelhead. And Logan Creek and Lost Lake are upstream from Clark Lake.

In Manitowoc County, DNR staff witnessed steelhead jumping over the dam at Mishicot on the East Twin River. There are no other dams upstream from Mishicot and as a result, the entire East Twin River and all of its tributaries in Manitowoc and Kewaunee counties are now considered to be VHS positive.

VHS rules consider VHS-positive waters to include all waters testing positive for VHS and all tributaries flowing into those waters upstream to the first dam capable of blocking upstream fish movement.

Fish from Lake Michigan were found to have VHS in 2007 and 2008. VHS affected waters are closed to all minnow harvesting. The only exception is that suckers can be taken but may not be transported away alive.

Tags: , ,

Switch to our mobile site