(WASHINGTON) - The Supreme Court won't order closure of shipping locks on Chicago-area waterways to prevent Asian carp from invading the Great Lakes.
The high court on Monday refused to hear an appeal from Michigan and other Great Lakes states, who have been trying for immediate shutdown of the locks and a quicker timetable for other steps to halt the carp's northward march from the Mississippi River toward Lake Michigan.
The high court already has rejected the request from Michigan, Minnesota, Ohio, Pennsylvania and Wisconsin twice.
The states have a pending lawsuit that calls for permanently severing a man-made link between the Mississippi and Great Lakes drainage basins. They wanted a court order to close the locks while their suit works through the courts.
On Thursday, officials announced that the Obama administration will spend $51.5 million this year to shield the Great Lakes from the carp, including first-time water sampling to determine whether the destructive fish have established a foothold in the lakes.
The updated strategy that includes stepped-up trapping and netting in rivers that could provide access to the lakes, as well as initial field tests of scents that could lure carp to where they could be captured.
With this year's money, the federal government will have spent $156.5 million over three years in the fight against bighead and silver carp. They have migrated up the Mississippi River and its tributaries including the Illinois River, where they've advanced to within 55 miles of Lake Michigan.
The carp eat massive amounts of plankton - tiny plants and animals at the base of the aquatic food web. Scientists differ about how widely they would spread in the Great Lakes, but under worst-case scenarios they could severely damage the $7 billion fishing industry.