"We're spending close to $80 million just for a short-term deterrent," said Joel Brammeier, president of Alliance for the Great Lakes. "We need to stop pushing money toward temporary solutions and get everyone on track toward investing in one that works for good - and that means absolute physical separation."

Bighead and silver carp - both native to Asia - have been migrating toward the lakes since escaping from deep south fish ponds and sewage treatment plants in the 1970s. Carp can reach 45 kilograms and over a metre long, consuming up to 40 per cent their body weight daily in plankton, the base of the aquatic food chain.

Once established in the lakes, Asian carp could starve out fish on which popular species, such as salmon and whitefish, depend.