I dont think the great lakes themselves are in danger directly of an asian carp invasion. The carps actually are filter feeders and don't eat much of anything else except what they filter out of the water. They will like the rivers much better than the big lakes, but here is the real danger which they will get too sooner or later- all of the streams, creeks, rivers, and tributaries that come and go into the big lakes. There are lots of them.
Every stream, creek, crick, river, tributary, waterway, etc that is connected to the Illinois river in my area is completely infested with the asian carps. Snagging is the only way to catch em with fishing gear.
Definitely need to make them worth some money so people will want to target them, but even then it seems like you would just be picking a corn field by hand.
