Ohio River carp Port Clinton
ZANESVILLE, Ohio — As it cuts a squiggly track through the southeast Ohio hill country, the Muskingum River might seem like an unlikely battlefront in the war to keep Asian carp out of the Great Lakes, but the results of a recent study indicate these dreaded invaders could be present near there, and pushing north toward a gateway to the Lake Erie watershed.
Multiple water samples taken from the Muskingum River in the fall of 2013 carried the environmental signature of bighead carp, an invasive species threatening the ecosystem of the Great Lakes. A report released Friday by the Nature Conservancy, in conjunction with the Muskingum Watershed Conservancy District, the Ohio Department of Natural Resources, and researchers from Central Michigan University, indicated 10 of the 222 samples from the river tested positive for bighead carp eDNA.
The eDNA means Asian carp genetic material, which could be from scales, body fluids, blood, waste, or live fish. Biologists use eDNA analysis of water samples as an early detection weapon to determine if Asian carp are present in a system. While eDNA is not as conclusive as the presence of live or dead fish, it does confirm the presence of Asian carp genetic material.
“I don’t want to think about what this might mean, ” said a stunned Darrell Gibbons, who has operated the D&D Bait and Tackle shop in Zanesville near the river for the last 18 years. “We catch a lot of catfish, bass, crappie, and walleye from that river, so this can’t be good news.”
Asian carp have been established in the Ohio River for more than a decade, but these most recent eDNA results indicate the fish could be present in the Muskingum as far north as the Ellis Lock 11 and dam, some 80 miles north of where the Muskingum joins the Ohio at Marietta. Samples from above the Ellis Lock did not show the presence of Asian carp eDNA, but they were taken in less than ideal carp habitat, according to John Stark, director of freshwater conservation in Ohio for the Nature Conservancy.
“These results are concerning, since they indicate the fish are moving up pretty far into the system, ” Mr. Stark said. “We’ll feel better about relying on the information once it is more conclusive, but it makes sense, since these fish have been in the Ohio River for some time.”
The Muskingum River has a series of old dams and deteriorating locks, but if the eDNA evidence is accurate, those have not provided a significant impediment to the carp moving up the river system.
“This information seems to indicate they have already gotten past the dams, ” said John Navarro, program administrator for the ODNR. “They’ve shown no tendency to slow down. They are barreling up these waterways.”
Through a link at Portage Lakes, south of Akron, the carp could conceivably use the Tuscarawas River, which flows into the Muskingum River, to access the Cuyahoga River system, which feeds into Lake Erie at Cleveland.
Water is actively moved between the two basins, Mr. Navarro said. “It is a direct connection, not nearly as big as some others, but one that is real complicated, with a number of jurisdictions involved, ” he said.
Closing that link is a priority for many involved in the Asian carp fight, which has been going on for at least two decades and involves a cadre of state and federal agencies.