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Threat facing fishing - Invasive species


From coast to coast and border to border, aquatic invasive species are degrading fisheries and diminishing angler access as they cause tremendous damage to the nation’s ecosystems and economy.

According to a 2004 report from Cornell University, “invading alien species in the United States cause major environmental damages and losses adding up to almost $120 billion per year.”

Although hundreds of exotic species now are established in our waters, a handful is wreaking the most havoc. They include Asian carp (bighead and silver), mussels (zebra and quagga), and aquatic plants such as Eurasian watermilfoil, hydrilla, and water hyacinth.

Water-Chestnut-Cleanup-Maxwell-CreekFor example, Asian carp now make up more than 60 percent of the total fish biomass in the main channel Illinois River. That means bass, bluegill, catfish, buffalo, and other native species now account for less than 40 percent of the population by weight that they once provided.

Additionally, bighead and silver carp are knocking at the door of Lake Michigan, as well as the Iowa Great Lakes and inland fisheries in Minnesota and Wisconsin. If they find tributary rivers in these waters to their liking for spawning, the invaders could devastate some of the nation’s best sport fisheries.

Quagga and zebra mussels, meanwhile, also threaten inland fisheries in the Upper Midwest, as well as the West. Angler and boater access likely will be restricted in many of these waters, as resource managers, lake associations and others, try to keep out the invaders.

You can help protect our waters from these invaders and lessen the threat of restricted access. Don’t move water, plants, or animals from one fishery to another. Don’t release live bait into a lake or river unless you obtained it from that same water. Inspect and clean your boat thoroughly before moving it from one fishery to another, draining and drying out the bilges and the livewells.

Solution: Inspect, clean and dry boats, boots and waders when you move between waters, and never dump your bait bucket.