No Asian carp found but concerns linger

Chicago - Despite an extensive search of the Chicago Ship and Sanitary Canal near Lake Michigan, no Asian carp were netted. Many warn this operation, and its failure to find an Asian carp, proves nothing.

Federal fishery crews are announcing they landed zero Asian carp despite having invested tens of thousands of dollars and a month of time searching the canal near Lake Michigan. The crews used nets and fish-shocking equipment in their hunt for the elusive foreign invader. But these results will not put an end to the large and growing argument: Should the Chicago Sanitary and Ship Canal be closed? The CSSC is the infamous man-made link between Lake Michigan and the Mississippi River basin. Over the years it has proven to be an inviting open door to invasive foreign species migrating between the two major, but once totally separate, water systems. Environmentalists warn Asian carp, released into the southern Mississippi River years ago, will soon use the canal to enter the Great Lakes. They bolster their argument with the fact that testing has revealed Asian carp eDNA present in water samples taken from the canal above all the barriers and even in some samples taken from Lake Michigan itself. Do these empty nets prove the canal near Lake Michigan is free of Asian carp? The answer is no according to University of Notre Dame environmental eDNA expert David Lodge. Using nets and electro-shocking gear one might harvest one percent of the fish in a body of water as large as the canal. It is dozens of miles long, wider than a football field and nearly three-stories deep in places. If there are only a handful of Asian carp present, the odds are stacked against the landing of an Asian carp in such a small sample. In December, $3 million was spent poisoning the CSSC with 2,200 gallons of rotenone, toxic to fish, in order to perform maintenance on the electric fish barrier in the canal. Among the thousands of fish killed below the barrier, only one 22-pound Asian carp was discovered. It has been dubbed the 3-million-dollar fish. "It is a waste of time and money," Tom Marks, New York director of the Great Lakes Sport Fishing Council, said of the government fish sampling operation just ended. According to the Milwaukee Journal:

Marks said it is ironic that the government is using fish nets and electro shocking to try to confirm what the DNA is telling them because it was the failure to find the fish with nets and shocking that drove the government to use the DNA technology in the first place.

The concern among those fighting to close the CSSC is that government-sponsored fishing crews returning empty-handed lessens pressure on government agencies to make a move opposed by the powerful shipping industry. Much attention has been focused on the warm-water discharges from the industries lining the CSSC. With the coming of spring, and soon summer, the warm water in the canal will encourage and facilitate increased movement of any Asian carp present. As a warning portending the billions of dollars in losses threatening the Great Lakes fishing industry, this is price tag put on the ecological havoc posed by Asian carp, the 3-million-dollar fish may have been cheap.