Photographer Lloyd DeGrane and his son, Sam, came well armed when they put in to the Illinois River at downstate Havana. Silver carp–which along with bighead carp floated out of agricultural ponds in Arkansas into the Mississippi River during the floods of the 90s and have been multiplying northward ever since–get riled at the sound of an outboard motor. The DeGranes’ garbage can lid barely did the trick. “At first Sam and I were just laughing,” Lloyd says. “Then I thought about how all these things are headed our way, hundreds and probably thousands.” Able to eat up to 40 times their own weight in smaller creatures, the monsters can grow up to 100 pounds. Now only an underwater electric fence at Romeoville stands between them and Lake Michigan.

Art accompanying story in printed newspaper (not available in this archive): photo/Lloyd DeGrane.