The invasive fish species known as Asian Carp may now have infested the Great Lakes system - meaning the fight to contain the giant fish to the Mississippi river and its tributaries may have failed.

Asian Carp have been a menace in the Mississippi River region and the fight against their migration has been centered on the Illinois River.  The Illinois, via a canal, connects to Lake Michigan.  The fear has been that if the species reaches Lake Michigan it can spread through the rest of the lakes and eviserate the natural species and disrupt the Great Lakes fishing industry.

This report from indicates that the carp have been spotted in lower Lake Michigan.

Of particular concern are silver and bighead carp, which gorge on plankton - microscopic plants and animals that virtually all fish eat at some point. The carp reproduce prolifically, and the biggest can reach 100 pounds.

Between September 2009 and October 2011, Jerde and his colleagues collected more than 2,800 water samples from parts of the Great Lakes and tributary rivers. The samples were poured through microfiber filters to extract DNA, which fish shed in their excrement, scales and body slime. It's known as environmental DNA, or "eDNA."

Laboratory analysis turned up 58 positive hits for bighead or silver carp in the Chicago Area Waterway System - a network of rivers and canals linked directly to Lake Michigan - and six in western Lake Erie. Some of the Chicago DNA was found in Lake Calumet, where a live bighead carp was caught in 2010.

"I would say there's at least some evidence for Asian carp being present in southern Lake Michigan," Jerde said. "The question is how many."

This is video of the large, jumping fish from the Wabash River in Indiana.