What is an invasive species?

Invasive alien species are plants, animals, or other organisms that are introduced to a given area outside their original range and cause harm in their new home. Because they have no natural enemies to limit their reproduction, they usually spread rampantly. Invasive alien species are recognized as one of the leading threats to biodiversity and impose enormous costs to agriculture, forestry, fisheries, and other human enterprises, as well as to human health.

• The cost to control invasive species and the damages they inflict upon property and natural resources in the U.S. is estimated at $137 billion annually.

Invasive Species: A Quick Look
The United States have been invaded by a number of harmful exotic plants and animals. Here is a quick look at some of the worst current and potential invaders by state:

What Congress Can Do:

A. Make Prevention Our Top Priority

• Reverse current U.S. policy on the intentional import of live plants and animals, that is, switch from a "dirty" to a "clean" list approach that requires screening for invasiveness before import and which keeps out or limits import of species so as to prevent harm to native species or ecosystems - and make the legislative changes to do so.
  
  
• Substantially cut the unintentional introduction of aquatic invaders by overseeing federal standard-setting on the discharge of ballast water in the United States, supporting the development of technology to meet these standards; ensuring that agencies monitor and enforce compliance; and reauthorizing the 1996 National Invasive Species Act in the strongest and most comprehensive form.
  
  
• When considering, reviewing, or approving trade agreements, rigorously address invasive species, e.g., by allowing for restriction of imports of non-native species that are invasive elsewhere and by identifying pathways by which inadvertent introductions travel so that they may be interrupted.

B. Make Federal Agencies More Effective

• Use oversight authority to ensure that all federal agencies immediately and strongly implement that part of Executive Order 13112 that asks them to identify and reduce actions that introduce or spread invasive species in the United States or elsewhere.
  
  
• Appropriate adequate funds so that federal agencies have the resources to address invasive species problems promptly and comprehensively over the long-term.
  
  
• Strengthen the structure and leadership of the National Invasive Species Council and prompt more aggressive implementation of its National Management Plan.
  
  
• Oversee the work of the U.S. Department of Agriculture's Animal and Plant Health Inspection Service to ensure that the agency and its Administrator are committed to protecting biological diversity as well as agriculture.
  
  
• Evaluate the serious problems with border inspection for pests, weeds, and pathogens, e.g., in staffing and cross-department coordination, exacerbated by moving these functions into the Department of Homeland Security and amend its authorizing legislation if needed.

Updated 8-10-05

Written by a partner: Alien Invasion: America's Battle with Non-Native Animals and Plants by Robert S. Devine with foreword by Bruce Babbit. Now in paperback! Click here to view Amazon.com listing.

From the Environmental Law Institute:

Making a List: Prevention Strategies for Invasive Plants in the Great Lakes States. Read more.

Invasive Species Control: A Comprehensive Model State Law. Click here to view.

Halting the Invasion: State Tools for Invasive Species Management. Click here to read more.