Two highly invasive species of Asian carp are knocking at the door of Lake Erie, putting its entire ecosystem at risk.
Asian carp have been a huge problem in middle American waterways, making their way to the last protective barriers to the Great Lakes. While officials have exerted great efforts to keep the invasive carp from entering Lake Michigan through the Illinois River, a recent report from the Washington Post warns that Lake Erie might be the next major waterway to be compromised.
A recent study warns that if the carp are allowed to enter Lake Erie, populations of popular native sports species like walleye and rainbow trout are likely to decrease as a result. The study used complex computer models to predict that bighead and silver carp, the two most ravenous invasive species of Asian carp, could replace as much as one-third of the total fish weight in Lake Erie.
According to Ed Rutherford, a biologist working with the federal Great Lakes Environmental Research Laboratory in Ann Arbor, MI, the invasive fish could take over Lake Erie quite rapidly. They have already overrun the Mississippi River and its connected streams and rivers, and their expansion appears to be halted only by the most extreme tactics.
While the two Asian carp species have made a name for themselves with their strange habit of wildly jumping out of the water when a boat drives by, they are quickly gaining notoriety as the single biggest threat to native freshwater ecosystems. The two carp species were imported to the South in the 70’s to clean out sewage treatment ponds, and quickly spread beyond the point of control.
A few individuals have been taken from Lake Erie in recent years, and their DNA has been found in various water samples taken from the lake. At this point, however, there is no apparent breeding population within Lake Erie.
According to Marc Gaden, a spokesman for the Great Lakes Fishery Commission, a joint agency between the U.S. and Canada, “It’s very sobering. Lake Erie is one of the most productive inland fisheries in the world. It wouldn’t be as valuable by any stretch of the imagination if one out of every three pounds of fish were Asian carp.”
The change once the carp make their way into Lake Erie would be rapid; the fish can consume up to 20 percent of their body weight each day. This would devastate the food chains in Lake Erie, as the hungry carp with no natural predators squeeze out native species for precious food supplies in the lake.
The study was published in the journal Transactions of the American Fisheries Society. The risk doesn’t face just Lake Erie, either – the research team that carried out the study is planning similar research for Lakes Michigan, Huron, and Ontario.
A press release from Notre Dame University describing the details of the study can be found here.