New Castle News

November 6, 2013

Our Opinion: Spread of Asian carp endangers major water system

By Staff
New Castle News

NEW CASTLE — When it comes to invasive species, Asian carp may not top the list.

But they receive plenty of well-deserved attention for their harmful impact on the environment. And sadly, it may be a problem destined to grow even worse.

Technically, Asian carp is a term applied to several species of bottom-feeding fish that were imported to this country over time for a variety of reasons. Some are innocuous and of no great environmental concern, such as goldfish.

But others, particularly the silver carp, can do considerable damage in a variety of ways. Perhaps you have seen videos of these fish leaping out of the water as they were frightened by passing boats. It’s more than mere entertainment; silver carp — weighing up to 100 pounds — have been known to injure boaters with their aggressive jumping habits.

That’s hardly the worst threat they pose. Silver and other Asian carp are prolific breeders and their tendency to vacuum plankton and other small food sources from the water starves out native species of various types.

For several years now, naturalists and those who make their living off sports fishing in the Great Lakes have been sounding the alarm in an effort to prevent Asian carp from infiltrating those waterways.

Elaborate steps have been taken to block the carps’ access, including electrified fences placed in various rivers and streams.

But the success of these efforts is uncertain. The Great Lakes represent a vast watershed between the United States and Canada. Despite millions of dollars spent trying to thwart the spread, many experts believe their expansion is inevitable.

And this week, it was reported a water sample taken in Lake Michigan contained DNA of a silver carp. That doesn’t prove the fish has succeeded in establishing itself in the lake (DNA can show up in a variety of ways), but it’s an obvious cause for concern.

If the most harmful types of Asian carp spread into the Great Lakes, it’s anticipated they will eventually decimate the populations of various native sports fish there, such as perch, bass and pike. Thousands of people employed in businesses that cater to sporting activities on the lakes will lose their jobs.

One solution might be to promote fishing for the carp. After all, if they top the scales at 100 pounds, they ought to be able to put up quite a fight.

Unfortunately, being bottom feeders that generally suck up microscopic nutrients, the carp are notoriously difficult to catch.

The solution? Some defenders of the Great Lakes argue that aggressive steps must be taken to divert waterways where the carp are found from entering the lakes.

But we’re not convinced that step will be enough. Humans transport bait and other fish all the time. A few careless people can do a lot of damage.

If ever an invasive species problem cried out for an imaginative answer, this is it.