CHICAGO -- The U.S. Army Corps of Engineers says it has more evidence indicating that the dreaded Asian carp is in Lake Michigan, making the announcement hours after the U.S. Supreme Court decided not to force Illinois to do more to keep the fish out of the lake.

Army Corps officials yesterday said researchers combing the Calumet Harbor near Lake Michigan for Asian carp have found two DNA samples that seem to indicate that the invasive fish has already breached the Great Lakes near Chicago.

The presence of carp DNA in the lake is not necessarily proof that the carp are already in Lake Michigan, officials have said in the past. After an earlier announcement of Asian carp DNA in a branch of the Chicago River that feeds into Lake Michigan near Wilmette, the Army Corps' Maj. Gen. John Peabody said, "This gives us a better indication of the presence of carp, but it's not foolproof."

Using a new system developed at the University of Notre Dame, researchers had found trace amounts of Asian carp DNA north of the underwater electronic barrier near Lockport, suggesting that at least some fish have found a way to bypass what was once called "the last line of defense." Researchers still aren't sure how any carp got beyond the electric barriers.

Earlier, the Supreme Court rejected a request from Michigan and other Great Lakes states to force Illinois to stop the water flow from its rivers into Lake Michigan. In a brief order, the justices said they had denied the "motion of Michigan for preliminary injunction."

The court's decision leaves it to state and federal officials in Illinois to prevent the voracious Asian carp from reaching the Great Lakes.

The boating and shipping industries welcomed the decision. Michigan's attorney general, who was among those on the losing side, urged President Barack Obama to step in and close the locks at the center of the dispute.

After Michigan filed its request before the high court, the justices were told that the Army Corps operates the locks between the rivers and Lake Michigan. For this reason, U.S. Solicitor General Elena Kagan had urged the justices to reject Michigan's motion. She said Michigan should have sued the Army Corps, rather than the state of Illinois.

It appears the justices took her advice and steered clear of the dispute between Michigan and Illinois. While the high court has rejected Michigan's request for a temporary injunction to close the locks, it could still issue a ruling on the broader aspects of Michigan's case, said a Natural Resources Defense Council spokesman.

Specifically, the Supreme Court could decide to rule on whether to reopen the 1922 case that created Chicago's Sanitary and Ship Canal and linked the Great Lakes to the Mississippi River. That ship canal is now the most direct route for Asian carp to enter Lake Michigan, a path biologists have referred to as a "super highway" for invasive species.

Reacting to the court's decision, Michigan Attorney General Mike Cox released a statement saying he was "extremely disappointed" in the ruling, but optimistic that the court eventually will consider the merits of the case. Mr. Cox also called on Mr. Obama to use his executive powers to close the Chicago-area locks to prevent the Asian carp's advance.

"I am extremely disappointed the Supreme Court did not push the pause button on this crisis until an effective plan is in place," Mr. Cox said in his statement. "While the injunction would have been an extraordinary step by the court, Michigan and the other Great Lakes states are facing an extraordinary crisis that could forever alter the Lakes, permanently killing thousands of jobs at a time when families can least afford it.

"President Obama said he would not tolerate new threats to the Great Lakes, yet he has left the front door to Lake Michigan wide open. Billions in economic activity and 800,000 Michigan jobs connected with the health of the Lakes are at risk. His indifference is just stunning."

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