There is now evidence Asian carp may have slipped into Lake Michigan, a development that could dramatically transform all of the Great Lakes because the large fish are known for dominating the waters they inhabit.
The warnings surfaced earlier this week during meetings of the Great Lakes Fishery Commission at Caesars in Windsor, where scientists are discussing the latest research on fish stocks, habitat and ecosystem for each of the Great Lakes.
The imported fish have been working their way up the Mississippi River for a decade, natural resources experts said.
Electrified barriers have been set up to keep them from entering the Great Lakes to stop the intrusion. However, new water testing in Calumet Harbour on Lake Michigan indicates the carp may have breached the barriers.
"The finding that there was in fact silver carp DNA in the Calumet Harbour is troubling for a lot of people because it fits this pattern of the carp moving north and getting through the electric barrier," said Dan O'Keefe of Michigan Sea Grant.
Asian carp are voracious eaters and compete for food with the fish most North Americans like to eat. Moreover, the warmer and shallower waters of Lake St. Clair and Western Lake Erie would make ideal spawning grounds for the fish, said Michael Hansen of the Great Lakes Fishery Commission.
"We don't know how long it would take and the fact that a few fish may have gotten past the barrier does not mean that we've lost this battle," he said. "It just means that we don't have much time to fiddle around with this question. We need to separate the two basins and do it now."
The U.S. federal and state governments are now funding efforts to search and destroy all Asian carp found in the lake to stop the fish from infiltrating the rest of the Great Lakes.