We have a rare opportunity here. In the past, we haven't learned about new invasive species in the Great Lakes until it has established itself and, usually, destabilized the ecosystem even further. With the Asian Carp (which is making its way toward Lake Michigan via the Sanitary and Ship Canal), we have a window of time in which to take action to prevent their arrival in the lake.
There are currently two electric barriers in the canal to stop the fish from reaching the lake, but there is concern that they may not be entirely effective. Recent testing of the canal water was positive for the asian carp DNA. This means that the fish are closer to the lake than previously thought.
(Photo: The Calumet River flowing into Lake Michigan)
The decisive step of poisoning a stretch of the canal to kill all fish there is happening today. This will allow maintenance to be done on the electric barriers and also allow researchers to find out if any of the carp have reached the barriers. Read about it in the Detroit Free Press article. This is not a permanent fix for the problem, though, and flooding of the Des Plaines River could sweep the fish past the electric barriers.
Shipping in the Great Lakes is a multi-billion dollar industry. It is this industry that has transported the majority of the invasive species (from around the world) to the Great Lakes. The zebra mussel (from the Caspian Sea), the quagga mussel (from the Ukraine), and the round goby (from Europe) all hitched rides in the ballast water of ships from fresh water ports around the world and were then dumped into our lakes. How costly is it to treat ballast water so that nothing survives from these far off ports to attack our lakes? Certainly nowhere near the billions of dollars that just these three invasive species have cost the Great Lakes.
There are two major ports on the south end of the lake. I walked by both of them. Ocean going vessels can dock here, then barges take goods inland via canals and rivers to the Mississippi. This is a multi-billion dollar industry. How costly, really, would it be to seal off the canals permanently and transport cargo a short way overland to nearby rivers that connect to the Mississippi? It can't be as costly as turning our lakes over to these voracious, invasive fish.