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Wildlife Protection

Keeping It Simple: Easy Ways to Help Wildlife Along Roads

Keeping out carp protects a lake

Freshwater carp severely reduce the numbers of aquatic plants and animals in lakes like the one along Highway 5 near Chanhassen, Minnesota. When feeding carp root around in the shallow waters of the lake, they stir up the mud on the lake bottom. The disturbance clouds the water, making it harder for fish to see the beetles, crustaceans, and other plants and animals they need for survival. So to keep carp from migrating into the lake, Minnesota Department of Transportation workers constructed an insurmountable gradient in the stream entering the lake. The carp can't swim over this concrete "hill," the water quality is improved, and thanks to increased sunlight penetrating the water, there's a greater diversity of aquatic plants and animals for the resident bass, bluegill, and other fish species.
--Apr 25, 2003

Frank Pafko, (651) 366-3602 or

Looking upstream into culvert that presents a barrier to carp migration
Photo by Greg Busacker, Minnesota Department of Transportation
Carp barrier on Riley Creek

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