The Great Lakes states are concerned about the potential spread of Asian carp, an invasive species not native to North America, into the Great Lakes. They fear the carp could have significant negative ecological and economic consequences for the region. For the past few years, these states have sought (unsuccessfully) to obtain an injunction requiring the closure of locks that could help prevent the carp’s spread.
Yesterday, the U.S. Court of Appeals for the Seventh Circuit rejected their petition, largely on the grounds that various state and federal efforts to contain the carp are underway. Judge Wood’s opinion for the court in Michigan v. U.S. Army Corps of Engineers summarizes:
. This appeal requires us to consider . . . the environmental and economic harm posed by two invasive species of carp, commonly known as Asian carp, which have migrated up the Mississippi River and now are poised at the brink of this man-made path to the Great Lakes. The carp are voracious eaters that consume small organisms on which the entire food chain relies; they crowd out native species as they enter new environments; they reproduce at a high rate; they travel quickly and adapt readily; and they have a dangerous habit of jumping out of the water and harming people and property. . . .
. . . 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. This effort diminishes any role that equitable relief would otherwise play. Although this case does not involve the same kind of formal legal regime that caused the Supreme Court to find displacement of the courts’ commonlaw powers in American Electric Power, on the present state of the record we have something close to it. 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.