From time to time, exotic species break loose inside our borders and start bullying their way around.

The kudzu carpets every green thing in its path. Carp from Europe dominate in places where native buffalofish once swam. Starlings and house sparrows shove other birds out of the way. And now here comes the snakehead fish.

From the Yellow River region of China, it has made its way to a pond in Maryland just 20 short miles from Washington, D.C.

A nasty member of the finny tribe, it can grow a yard long, has pointed teeth, eats other fish, ducks or whatever and reproduces like crazy. The snakehead fish can live on land two or three days, breathing by virtue of capillaries in its mouth.

The fish wiggles across the terrain on its fins and may eat small mammals along the way.

The secretary of the interior has called this Frankenfish “something from a bad horror movie.”

Ed Wiley, a Kansas University ichthyologist, is under contract to map how far west the snakehead could spread. It’s one of about 20 temperate-climate Asian and European species that Wiley is studying. For each, he’s constructing maps that show where they might find life bearable.

Could the snakehead make it in Kansas?

Wiley said that the species found in Maryland could survive in most of Kansas. That’s an extremely preliminary finding based on a quick and dirty analysis performed by Lifemapper, a species mapping project at the KU Biodiversity Research Center.

Wiley is early in his threat assessment of the temperate-climate fishes.

He’s doing the work for the U.S. Geological Survey with funds from the Florida Caribbean Science Center.

He’ll also be predicting the habitat range of the zander, a European equivalent of our walleye; the European catfish, which can attain a size of several hundred pounds; and the black carp, which is captive today but inevitably won’t be, Wiley said.

How does Wiley map the potential range of these species? First, he builds a profile of the habitat the species came from. It includes two to four dozen factors, such as annual rainfall, temperature and elevation. Computers then identify geographic areas in the United States that match the species’ environmental requirements and predict where it might flourish.

Now please don’t grumble about pest species winding up on our fair shores.

After all, the fish most widely scattered across the world by humans is our very own largemouth bass. This bully has found its way into about 100 countries, Wiley said.

The Japanese introduced it in the 1930s, he said, and now they’ll never eradicate it. The more recently introduced smallmouth bass also ours represents a threat to Japanese river salmon.

“We export some pretty bad top predators,” Wiley said.

New York Times reporter Andrew Revkin summed up things from a broader perspective.

He wrote: “Humans have become a biological blender, carrying West Nile virus to America and overrunning the Bordeaux countryside in France with American bullfrogs that residents say do not even taste good.”

For better or worse, being a biological mixmaster is one of the perks that comes with our being the planet’s No. 1 predator.

Here’s hoping that we’ll learn to wear lightly the mantle of authority we so often and so automatically presume is ours.

Roger Martin is a research writer and editor for the Kansas University Center for Research and editor of Explore, KU’s research magazine Web site, which can be found at www.research.ku.edu. Martin’s e-mail address is rmartin@kucr.ku.edu.