As trout and salmon from Lake Michigan begin swimming upstream this fall in their ancient spawning ritual, the state Department of Natural Resources is taking new measures to minimize the risk of spreading a deadly fish disease.

The disease, called viral hemorrhagic septicemia, was detected last spring in fish from Lake Michigan and the Lake Winnebago system.

"There have been significant die-offs of fish already in the lower Great Lakes, ' ' said Bill Horns, Great Lakes fisheries specialist for the DNR. "We want to stop that from happening up here, or at least slow it down or minimize the areas where these disease outbreaks occur."

In response to the virus, the DNR is limiting the destinations for eggs collected from Lake Michigan fish. It 's also increasing its iodine disinfection tactics and collecting more fish samples for viral testing.

Eggs collected from Lake Michigan fish will be kept only at hatcheries within the Lake Michigan basin, and the fish will be stocked only into waters in the Lake Michigan basin, Horns said.

Lake Michigan 's trout and salmon populations depend on stocked fish that start as eggs collected at three DNR collection spots, or weirs, on the Root River in Racine, the Kewaunee River near Kewaunee and Strawberry Creek near Sturgeon Bay.

Strawberry Creek is the primary chinook egg collection site; the other two also collect chinook and capture coho, steelhead and brown trout for spawning later in the year.

Rules to prevent boaters and anglers from spreading the virus will be considered by the Natural Resources Board Oct. 24.

-- Anita Clark

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