Saturday, July 17, 2010

When invasive species get loose they often turn into monsters

The offices of Landscape Management magazine in Cleveland are just blocks from Lake Erie.

There’s a monster at our doorstep, our lakefront. It threatens incredible harm. This monster is an invasive species, the Asian carp, and the only thing keeping it from damaging the ecology of our Great Lakes and its multi-billion dollar sports fishery is an electrified fence in the Chicago Sanitary and Ship Canal.

If (when?) this fish makes its way around the barriers and into Lake Michigan it will be only a matter of time before it will spread to the other great lakes putting native species such as lake trout, walleye, whitefish bass and white perch (to name a few) in peril. The Asian carp is a voracious feeder and gobbles up much of the same food as these fish. The only difference being that the Asian carp can grow to 100 lbs. Anybody ever see a 100 lb. walleye?

Wherever the carp establishes itself the populations of native fish decrease. And the Asian carp has been establishing itself in many of our Midwestern river systems ever since escaping from southern farm ponds into the Mississippi River during the disastrous Midwestern floods of the early 1990s. Apparently catfish farmers had put them in their ponds to eat algae and other scum that, apparently, the carp are pretty good at doing.

The plant world has its share of invasive monsters, as well. One of the worst, the giant hogweed, is on the loose. It's horrific in a different sense than the carp. The giant hogweed's sap can cause severe, long lasting swelling and blistering to humans and animals. If sap gets into your eyes it can cause temporary and sometimes permanent blindness.

This problem plant can grow to a height of eight to 15 feet. Native to the Caucasus, it’s believed giant hogweed was brought into the United States and Canada as an ornamental, but it does particularly well where the soil has been disturbed, such as along railroads, abandoned construction sites and vacant, weedy fields. If conditions are right, it can dominate an area.

To date, giant hogweed has been reported in several eastern Canada provinces and from Maine to Michigan and as far south as Virginia in the United States.

Once established invasive species are often impossible to eradicate. Hundreds of millions of dollars have been spent controlling them, and many hundreds of millions more will be spent as the battle against harmful invasive species is literally never ending.

Click here for a good description of giant hogweed.

No comments: