Here is a dead Carp, an invasive species introduced to the Great Lakes by foreign freighters illegally pumping their bilges into the lakes and through locks at Chicago that connect to the Mississippi system which is already infested. This Carp is a real menace because it kills native fish. It was killed by a Sea Lamprey, another invasive species introduced the same way. The grey mark on its side is a Lamprey bite. The Lamprey is an eel-like thing that attaches itself to fish and sucks out their internal juices. Yuk all around.