They are some of the most acrobatic fish you'll ever encounter, hurtling their silver bodies high out of rivers when motorboats pass by. But Asian carp that have been invading the Mississippi River drainage the past two decades pose a serious threat to both the native fish in the Great Lakes and Minnesota's waters and to regional economies.
Capable of growing to 4 feet in length and 100 pounds in weight, these carp can take over ecosystems. Asian carp, which are filter feeders, were introduced to the United States in the 1970s to help keep wastewater treatment facilities and aquaculture ponds clean. But floods in the 1990s enabled them to reach the Mississippi River, and they've been headed north ever since. If the carp reach Lake Michigan and spread to the other Great Lakes, it's feared that they'll quickly overwhelm the lakes' $7 billion sport fishery.
Since 2011, the National Parks Conservation Association has led a coalition to halt this invasion at the Mississippi National River and Recreation Area and the St. Croix National Scenic Riverway.
'We've got to get some policy in place to protect our recreation and our native fish populations, both of which support our multi-billion dollar tourism industry and thousands of jobs and businesses,' says Lynn McClure, director of NPCA's Midwest Region.
Over the last few years, Asian carp have been caught in several places in the Mississippi River in Minnesota within the Mississippi National River and at the mouth of the St. Croix River. Blocking their way to the Great Lakes has been the Chicago Sanitary and Ship Canal that connects the Illinois River to the Great Lakes. The U.S. Army Corps of Engineers maintains three electric barriers in the canal system to prevent Asian carp from entering Lake Michigan, but a recent study by the Corps and U.S. Fish and Wildlife Service indicates that fish can get beyond the barriers by traveling in a barge's wake.
Elsewhere in the Midwest Region, officials are keeping an eye on development of a General Management Plan to guide oversight of the Ozark National Scenic Riverways in Missouri. Long needed to protect 134 miles of the Jacks Fork and Current rivers, the draft GMP aims to better control horse access, camping, off-road vehicle use, and motorboat travel in the rivers, all of which will protect the water quality of these rivers and preserve the atmosphere that Congress intended when creating the nation's first Wild & Scenic River.
'What's happened over the last 30 years, is that an increase in motor boat use that wasn't historically allowed in parts of the river has really made an impact on canoe and kayakers,' says NPCA's Ms. McClure. 'We hope paddlers will make their voices heard and call for a quieter Ozark.'
You can participate in NPCA's efforts to restore Midwest national park waterways and restore the Great Lakes at this site. npca.org/midwest
Next Monday: Hog Farm Poses Threat To Buffalo National River