Propellers' noise sends violent carp out of rivers, into boats

ST. LOUIS -- This is no fish tale: A state fisheries biologist motoring on the Missouri River near Columbia had a filling knocked out of his tooth by a high-jumping fish that hit him on the side of the head. Another state biologist in the St. Charles area was seriously hurt when he was struck by a giant carp.

Sound fishy? The stories are true, a state conservationist said in getting the word out about two species of nonnative carp that have jumped violently into boats, injuring occupants and damaging the watercraft.

Brian Todd of the Missouri Department of Conservation, in a story first reported in the Moberly Monitor-Index and Evening Democrat, said the big head carp and silver carp were brought to private fish hatcheries from Asia by the aquaculture industry. They were intended to eat excess algae and waste in aquaculture ponds -- which grow fish for food as well as bait and tropical fish. But they escaped in floodwaters in 1993, 1995 and 2002.

"This could be an indefinite problem," Todd said.

Todd said the carp have been spotted in many of Missouri's rivers, including throughout the Missouri River, the Chariton River in north-central Missouri, the Gasconade River, the Grand River near Chillicothe, and in the lower Osage River.

The state of Illinois and the federal government have built a barrier composed of a series of electrodes that they hope will keep Illinois River carp from traveling to Lake Michigan.

Todd said an Asian carp found in Illinois weighed 60 pounds, but the ones found in Missouri weighed around 15 pounds.

"The sound of a propeller under water makes these fish go crazy," Todd said. "The fish don't jump if you're sitting there without the motor on, but the higher the RPMs, the greater the noise, the higher these fish jump."