[JURIST] The US Court of Appeals for the Seventh Circuit [official website] on Wednesday ruled [text] against five states in their latest efforts to stop Asian carp [EPA backgrounder] from overrunning the Great Lakes. Officials fear that the 100-pound fish, which reproduce rapidly, could wipe out native species and destroy the $7 billion Great Lakes fishing industry. Although all parties agree the fish need to be dealt with, there is disagreement as to how. Illinois, the Obama administration, the Environmental Protection Agency (EPA) and the US Army Corps of Engineers [official websites], thus far the prevailing parties, stand behind the Asian Carp Control Strategy Framework [text, PDF], a law that encourages aggressive hunting and control of the fish species before they enter the Great Lakes. However, the plaintiffs, the states of Michigan, Minnesota, Ohio, Pennsylvania, Wisconsin and several intervening organizations, believe the best strategy would be to close two waterways in Chicago that allow the carp to reach the Great Lakes. The three-judge panel, although ultimately rejecting Michigan’s request for an injunction, cautioned the federal government and Illinois on letting the carp population get out of control.

We are less sanguine about the prospects of keeping the carp at bay. In our view, the plaintiffs presented enough evidence at this preliminary stage of the case to establish a good or perhaps even a substantial likelihood of harm—that is, a non-trivial chance that the carp will invade Lake Michigan in numbers great enough to constitute a public nuisance. If the invasion comes to pass, there is little doubt that the harm to the plaintiff states would be irreparable. That does not mean, however, that they are automatically entitled to injunctive relief. The defendants, in collaboration with a great number of agencies and experts from the state and federal governments, have mounted a full-scale effort to stop the carp from reaching the Great Lakes, and this group has promised that additional steps will be taken in the near future. … In light of the active regulatory efforts that are ongoing, we conclude that an interim injunction would only get in the way. We stress, however, that if the agencies slip into somnolence or if the record reveals new information at the permanent injunction stage, this conclusion can be revisited.

Several of the attorneys general involved have made statements [AP report], including Wisconsin Attorney General JB Van Hollen [official website]. Van Hollen, in a press release [text], said: “I believe the aggressive actions taken by Wisconsin and the other plaintiff states have forced the federal government to take this issue more seriously, and the Seventh Circuit acknowledges as much by suggesting that preliminary relief may very well be granted in the future, should the federal government’s efforts wane.” There is no indication that the states plan to appeal to the US Supreme Court [official website].

The Supreme Court has denied certiorari [AP report] on the issue three times as of April 2010. The state of Michigan in December 2009 filed a lawsuit [JURIST report] in the Supreme Court against the state of Illinois seeking to close the two waterways, as the court has original jurisdiction in disputes between the states. All three times, the court denied certiorari without comment on the dispute. Michigan reopened the longstanding controversy [backgrounder, PDF] over the diversion canal, created in the 1890s to keep Chicago’s sewage from flowing into Lake Michigan. The court issued decrees over the canal in 1930, 1933, 1956, 1967 and 1980. The carp have been traveling up the Mississippi and Illinois rivers for years. Tests have showed that the carp may have gotten through an underwater electric barrier and may now be within six miles of Lake Michigan. The fish were originally imported to control algae in fisheries on the Mississippi River, but escaped during a 1990s flood.