Silver and bighead carp don't appear to be living and breeding in Lake Erie - yet.
Environmental DNA from the fish was found in the lake near the Maumee River last year. Environmental DNA comes from things like fish mucus, excrement, or scales.
But no Asian carp were captured in a recent electrofishing survey, which temporarily stuns fish with an electrical current.
Todd Kalisch is with the Michigan Department of Natural Resources.
He says the survey is pretty good news. He says keeping the fish from gaining a foothold is the only way to protect the Great Lakes.
"It would be extremely difficult if not nearly impossible to eradicate them - once - if they ever were to establish in a water body that size."
Kalish says researchers are keeping an eye on Lake Erie, on the chance that invasive carp in the Sandusky River could migrate to the Maumee River during a flooding event in the plain that separates the two rivers. From there, the fish could get to Lake Erie.
But Kalish says the biggest risk is posed by the Chicago River, which leads to Lake Michigan.
He says Michigan, Ohio, Indiana, the U.S. Wildlife and Fish Service, and the U.S. Army Corps of Engineers are collaborating, sharing results, and conducting joint projects to attack the problem.
Researchers also recently took samples from Lake Erie near the Maumee River to see if there are new traces of carp environmental DNA. Results are expected later this month.