CHICAGO — Genetic material from the Asian carp, a voracious invasive species long feared to be nearing the Great Lakes, has been identified for the first time at a harbor within Lake Michigan, near the Illinois-Indiana border, ecologists and federal officials said Tuesday. A second DNA match was found in a river in Illinois within a half-mile of the lake, according to scientists at the University of Notre Dame who tested water samples and provided the results to officials last week.
Experts said the most recent findings, from Calumet Harbor and the Calumet River, could mean that the carp has found its way beyond an elaborate barrier system built at the cost of millions of dollars to prevent the fish’s access to the Great Lakes and its delicate ecosystem, where it has no natural competitors and would threaten the life of native fish populations. “It’s a big admission of failure,” said Henry Henderson, the director of the Midwest program at the Natural Resources Defense Council. “It indicates the kind of thing we’ve been fearing since 1993.”
Government officials were careful to underscore that they had not found any fish — dead or alive — despite much effort, and that the Asian carp’s DNA could have arrived in Lake Michigan by various means other than the fish’s swimming from river basins it has already overtaken farther south. “Because we don’t know for sure that the source of the DNA is live carp, we’re taking it as an early warning that it may be live carp,” Maj. Gen. John W. Peabody of the Great Lakes and Ohio River Division of the United States Army Corps of Engineers said during a conference call to announce the findings. “As to how they got there,” General Peabody said, “the short answer is we don’t know, and there’s probably no way for us to ever tell.”
Still, Great Lakes advocates and the expert who conducted the tests seemed more convinced of the fish’s physical presence in or near Lake Michigan. “I think there’s not another plausible explanation for the presence of DNA that we’ve found other than that there are live fish in the vicinity,” said David M. Lodge, a professor of biological sciences at Notre Dame, whose team tested the water samples.
EDIT
http://www.nytimes.com/2010/01/20/science/20carp.html