Wednesday, August 4, 2010
In June, a commercial angler netted a 19-pound Asian carp on Chicago's Lake Calumet, part of the waterway system that connects the Mississippi River to Lake Michigan. The fisherman's haul was ominous, suggesting that the carp, had somehow gotten past an underwater electric fence designed to keep the species from entering the Great Lakes. But these are not the only alien species to threaten the lakes. Zebra and quagga mussel and the sea lamprey have also found homes in the lakes' waters. Asian carp's impact is nothing compared to the mussel's, which reduce rapidly and devour plankton and disrupt lower levels of food chain. This problem with invasive species washing into U.S. waters has come about thanks to international shipping. Click here to read more on Asian carp and mussels in the Great Lakes.