Carp

Sounds like a problem:

CHICAGO (Reuters) - Fish that leap into passing boats may be a fisherman's fantasy, but scientists fear that hyperactive Asian carp will reach the U.S. Great Lakes, devour the base of the food chain and spoil drinking water for 40 million people.
In less than a decade since escaping southern U.S. fish farms, the hardy and voracious carp have come to dominate sections of the Mississippi River and its tributaries.

Yeah, those fish farms are in Arkansas. Unclear why they're being farmed here. Unless they're different from the indigenous carp -- and they must be -- carp are virtually inedible.