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Wildlife Protection

Keeping It Simple: Easy Ways to Help Wildlife Along Roads

Improving trout habitat with "lunker structures"

White Pine River along Highway 33 north of Cloquet, Minnesota, is prime habitat for brown and brook trout. When the river had to be re-channelized, Minnesota Department of Transportation biologists placed "lunker structures" at the outside bends of the new channel to create cover runs for the trout. The structures look like giant rock-topped oak pallets with a cantilevered side buried inside the bank. Locating them at the river bends enables the current to clean the area between the "pallet" floor and roof. In the straight sections, log drop structures create small waterfalls and deep-water resting pools. Together, the two habitat-improvement devices are working well to protect trout from predators and to keep the river channel stable.
--Apr 25, 2003

Frank Pafko, (651) 366-3602 or

Photo showing completed structures along bank of White Pine River
Minnesota Department of Transportation photo
Lunker structures on White Pine River

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On or Along Waterways - Minnesota
Updated: 12/12/2012
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