Eco-Justice Ministries  

Eco-Justice Notes
The E-mail Commentary from Eco-Justice Ministries

Deadly Invaders
distributed 9/10/04 - ©2004

What is the nastiest invasive species in your neighborhood?

Invasive species are plants and animals that are transported -- accidentally or intentionally -- from one part of the world to a new location. They become "invasive" if there are no natural controls on their growth in that new setting. Without those limiting factors, the invasives are prone to take over their new locales.

Think of kudzu, an ornamental vine that is ravaging the southeastern US, smothering trees and houses, and pulling down utility wires.

Zebra mussels are little shellfish that were brought to the Great Lakes in the bilge of ships. Without natural predators, their populations have exploded, crowding and starving out many other species, and choking the inlet pipes for municipal water systems.

In the western US, tamarisk is a big problem. Imported to control erosion, it has taken over stream banks, crowding out all other plants, without providing decent food or suitable shelter for the diverse wildlife that used to populate those riparian areas.

Another problem -- especially in the Great Basin of Utah and Nevada -- is cheat grass, a hardy plant with almost no nutritional value for wildlife or livestock. It spreads quickly, puts down deep roots that allow it to thrive in droughts, sprouts early to crowd out the native bunch grasses, and burns with such heat that a prairie fire kills all other plants. Bighorn sheep, elk and mule deer now come down to their traditional wintering grounds and starve to death because cheat grass has become the dominant vegetation.

A study by Cornell University found that 400 of the 958 species protected by the Endangered Species Act are at risk because of competition from invasive species. A US Department of Agriculture report says that invasives constitute "one of the most serious economic, social and environmental threats of the 21st century."

The problem species vary depending on the local conditions. But the hallmarks of the situation are the same every time. A vigorous new competitor disrupts, changes, and impoverishes a diverse, healthy ecological system. They don't tend to support biological diversity. Indeed, they are successful precisely because they are not a good food source for the existing wildlife. Invasive species don't bring flourishing life along with them. They take over by eliminating everything else.

The plants and animals that become "invasive" in new locations are remarkable in their success. In terms of their own ability to flourish, they out-compete all of the native species. The deep concern that invasives cause among biologists and resource managers shows, though, that the stunning success of one species is not good for the system as a whole. When one species takes over, the diversity and resilience of the system suffers.

Controlling invasive species requires active management of ecosystems, often with lots of herbicides or pesticides. Committed environmentalists who ordinarily want "nature to take its course" should support programs that seek to control the destruction caused by invasive species. Those control programs are expensive and difficult. But many communities gladly make that investment, knowing that their part of the world will be diminished -- biologically and economically -- if the invaders take over.

+     +     +     +     +

I see an interesting parallel between the long-standing problem of invasive plant and animal species, and a newer problem in global economics.

This newer problem has many faces and many expressions. They are businesses that are such aggressive competitors that they displace existing, previously healthy, companies. The best-known and most wide-spread of these "invasives" is Wal-Mart.

Let me apply a slight variation of the biological description that I just gave. A vigorous new competitor disrupts, changes and impoverishes a healthy, diverse economic system and community. They don't tend to support economic diversity. Indeed, they are successful precisely because they pay low wages and low taxes. The invader doesn't bring flourishing life along with them. They take over by eliminating everything else.

A year ago, the spread of full-scale grocery departments in discount mega-stores was a major factor in Southern California's grocery strike. The invasive chains use the muscle of their global networks to lower costs. They hire part-time and non-union workers, and don't provide benefits. They negotiate lucrative tax deals with cities. The discounters are forcing out the established grocers, and lowering wage scales for an entire industry.

In the plant and animal world, we know that out-competing the natives may be "success" for the invasive species, but it spells disaster for the ecosystem. It is appropriate, even essential, to control the super-aggressive newcomer for the sake of the larger community.

It is time to take a similar look at the invasive species of the economic world. The ability of one company, or type of industry, to out-compete the established businesses may be "success" for that one firm, but a disaster for the broader community. It is appropriate, even essential, to control the aggressive competitor for the sake of the larger community.

New strategies, like a requirement for a "living wage" at businesses that get major tax breaks, can bring appropriate control to the industries that are invading our communities.

Oh, a final note. Don't forget to think about humanity as the world's most successful "invasive species." It is long past time to rethink whether the booming population and massive global impact of our own species constitutes "success" for the health of the earth.


Peter Sawtell
Executive Director
Eco-Justice Ministries

Eco-Justice Ministries   *   400 S Williams St, Denver, CO   80209   *   Home Page:
Eco-Justice Ministries ended all programming on July 31, 2020. This site is an archive of writings and resources.
To contact a representative of the agency by e-mail, please use the contact form