Fish kills expected in northwestern Wisconsin

[Lee Borgersen]

Fish kills expected in northwestern Wisconsin lakes
News Release Published: June 20, 2011 by the Northern Region

Contact(s): Jamison Wendel, DNR fisheries biologist, Spooner, 715-635-4095; Terry Margenau, DNR fisheries team supervisor, Spooner, 715-635-4162; Ed Culhane, DNR communications, Eau Claire, 715-839-3715

SPOONER – Biologists say conditions are ripe for fish disease outbreaks and fish kills on lakes in Polk, Barron, Washburn and Burnett counties during the next few weeks.

Reports of small fish kills on various Polk County lakes started coming in this past week, officials said. The cause is a bacterium called Columnaris, which infects fish species only and is not a risk to humans.

“The bacteria are most prevalent in our lakes after water temperatures reach 65 to 70 degrees from late May to late June,” said Jamison Wendel, a fisheries biologist with the state Department of Natural Resources.

Bluegill, crappies, yellow perch and bullheads – already stressed from seasonal spawning activities – are most affected by the disease. Cold or fluctuating water temperatures during spawning can compound spawning stress and weaken immune systems. The bacteria erode the skin on infected fish causing leakage of bodily fluids and rapid death.

Although Columnaris can appear to produce large-scale fish losses in a matter of several days it usually does not have a catastrophic impact on overall fish populations, biologists said.

If anglers or landowners in Polk, Barron, Washburn and Burnett counties have additional questions or see large numbers of other dead fish like carp, largemouth bass, muskie or walleye, they can contact DNR fisheries biologist Jamison Wendel at 715-635-4095 or fisheries team supervisor Terry Margenau at 715-635-4162.