Evidence that destructive Asian bighead carp may have moved into the Muskingum River watershed has officials concerned that the fish have found a shortcut toward the waters of Lake Erie and the entire Great Lakes system.
“The concern for bighead and silver carp is that these fish are filter feeders that consume plankton and other microscopic organisms for food. But sportfish and other native fish also use plankton for food during their early life stages, so there’s a potential food competition between these species,” said Rich Carter, executive administrator with the Ohio Department of Natural Resources Division of Wildlife.
Bighead carp environmental DNA (eDNA) was discovered in 10 out of 222 water samples collected last fall from several locations along the Muskingum River during a collaborative effort by the Muskingum Watershed Conservancy District, The Nature Conservancy, Central Michigan University and the ODNR Division of Wildlife.
The Asian carp, which include both bighead and silver carp, are non-native invasive fish that have already been discovered in the Ohio River at Portsmouth and as far upstream as the Hannibal Locks and Dam.
Environmental DNA collected in the water samples may have been deposited as fish swim through the water, shedding scales, blood and tissue. But Carter noted that other factors like fish-eating bird droppings could also carry the eDNA into an area.
Silver carp eDNA was not found in the samples collected last fall. The silver carp has gained some notoriety as it can leap out of the water and fall into fishing boats or other vessels.
“Like the zebra and quagga mussels that entered the Great Lakes 20 years ago and have spread throughout Ohio, Asian carp are filter feeders that consume the very foundation of the food web,” according to John Stark, director of freshwater conservation in Ohio for The Nature Conservancy.
Although no live bighead carp have been found in the river, the genetic material discovered from the eDNA tests seem to indicate the fish may be present as far north as 80 miles above the Muskingum’s confluence with the Ohio River at Marietta, according to Carter.
“But there have been documented accounts of live bighead carp caught in the Ohio River just upstream from Marietta since 1997,” he said. “And I’ve been told one angler caught a bighead back in the 1980s.”
Carter said Asian carp were introduced into the U.S. in the 1960s on an experimental basis.
“They were used to clean the algae growing in sewage lagoons,” he said. “Later they were being raised in farm ponds in Arkansas where flooding introduced them into the Arkansas River.”
From there the carp made their way into the Mississippi River basin and began moving upstream into other rivers, including the Ohio and its tributaries.
Jesse Daubert, watershed coordinator for Friends of the Lower Muskingum, said the presence of Asian carp in the Muskingum River is definitely a concern for that group.
“We know how destructive these carp can be to native fish habitat, and we’re willing to assist the larger agencies like ODNR in efforts to control these fish,” he said. “Invasive species, whether fish or plant life, can be difficult to get rid of once they’re established in an area.”
Asa Boring with the Little Hocking Bassmasters Club said he’s familiar with the damage carp can do and it’s a concern for fishermen.
“They don’t eat other fish, but they will eat grass and other plants, and they can eat a lot,” he said. “If the carp destroy all the grassy areas where smaller fish often hide, those fish will be easily found and eaten by larger fish before they can grow.”
Newport resident Harold Sliker spends a lot of time fishing on the Ohio and Muskingum rivers.
“I’ve caught buffalo suckers and regular carp, and have seen large paddlefish and catfish, but no bighead carp so far,” he said.
Carter said ODNR’s Division of Wildlife is continuing research on both bighead and silver Asian carp.
“The ODNR will coordinate actions to verify the positive eDNA results with the U.S. Fish and Wildlife Service, MWCD, and The Nature Conservancy, including conducting additional eDNA sampling and field sampling for live fish,” he said.
Area fishermen can help, too, Carter said, by taking a photo, if possible, and reporting any catch of a live bighead carp to the ODNR on the agency’s website at wildohio.com, or calling 800-WILDLIFE.
The MWCD provided $46,000 for the eDNA study, said Darrin Lautenschleger, public affairs administrator for the district.
“The kind of information that can be obtained from this study will help determine whether there is any danger that the carp may be present in any of the MWCD’s lakes or in the feeder streams and tributaries throughout the watershed,” he said.