For years, boaters and fishermen on many Midwestern rivers have battled a fish with a bizarre behavior -- silver carp that launch themselves into the air, jumping into boats and often slapping the unsuspecting upside the head.
ST. LOUIS For years, boaters and fishermen on many Midwestern rivers have battled a fish with a bizarre behavior -- silver carp that launch themselves into the air, jumping into boats and often slapping the unsuspecting upside the head.
"They can break your nose or knock you out of the boat," said Duane Chapman, a fisheries biologist with the U.S. Geological Survey.
The carp, brought to the U.S. from Asia by private fish farmers 30 years ago, are more than a nuisance to people. The silver carp and their non-jumping relative, the bighead carp, compete with native fish for food such as paddlefish, bigmouth buffalo and gizzard shad. They have established themselves in parts of the Missouri, Mississippi, Ohio and Illinois rivers.
Problem is, there's little profit for commercial fishermen in harvesting the fish. But the St. Louis Zoo may be the answer to that dilemma.
Rob Hayward, a University of Missouri-Columbia fisheries researcher, and Chapman are part of a team of researchers seeking to create a carp product to feed to zoo animals.
"We want to make good food of bad fish," said Ellen Dierenfeld, staff nutritionist at the zoo.
The zoo, one of the nation's largest, annually purchases as feed more than 60 tons of fish -- mostly marine species such as mackerel, herring and capelin. Prices range from 30 cents to 70 cents per pound, and zoo officials believe they could save money by feeding the carp to animals.
Dierenfeld believes up to 25 percent of the fish feed could be replaced with carp. "This would help reduce pressures on marine fisheries and help solve the Asian carp problem," she said.
And if the more than 200 accredited U.S. zoos did likewise, commercial fishermen would have a reason to harvest the nuisance fish.
University of Missouri-Columbia food scientist Andrew Clarke has developed a "carp cake" made from raw, ground fish, a process that allows different size feed for different animals. Dierenfeld said vitamins and mineral supplements could be added to the carp cake.
Dierenfeld hopes to begin a pilot feeding study with penguins, sea lions and pelicans by next spring. Other zoos may also participate, she said.
The Asian carp were imported in the 1970s as a way to control algae and plankton in fish ponds. But during the floods of 1993 and 1995, the fish made their way into the wild.
It is believed the silver carp jump out of the water as a flight response when disturbed -- possibly by the sound of the passing motor boat.
The high-jumping fish can be so dangerous that Missouri Department of Conservation staff wear head gear for protection while motoring on fast-moving boats. Some have protective netting around the driver area and across the bow.
The U.S. Fish and Wildlife Service earlier this month published a proposed rule to ban the import and interstate transport of silver carp.
Source: Associated Press