ST. PAUL, Minn. (AP) — Biologists at the Minnesota Department of Natural Resources are concerned zebra mussels may be hitchhiking on boat lifts.

The DNR says a second case recently was discovered on the northeast corner of Lake Irene in Douglas County. A localized population of zebra mussels was found on a lift last weekend.

A similar case was discovered at Rose Lake in Otter Tail County in late September.

At Lake Irene, the DNR was called in to investigate zebra mussels found on a boat lift recently removed from the water. The DNR suspects the pests were transported to the lake this summer when the boat lift was moved in from an infested lake.

The DNR plans to treat the small area with copper sulfate, used to treat snails that cause swimmers itch.

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