Photo Gallery: Go>>
In less than ten years, non-native zebra mussels that were stowaways on ships from Europe have infested America's waterways, clogging inlets and pushing local species of freshwater shellfish to extinction.
Over the same period, America's western corn rootworm hitched a ride on a commercial flight to Belgrade and has since been munching the heart out of Europe's farmland.
And in the U.S. Everglades, a noxious pest plant from Australia called the melaleuca tree is crowding out native vegetation, prompting scientists to import predator bugs from Australia in an effort to curb the spread.
These pests are prime examples of how global trade has spread invasive species around the world, sometimes grossly upsetting the balance of nature. Introduced species often find no natural enemies in their new habitat. They spread easily and quickly, many times ousting native species.
Read about the economic damage and the menace to indigenous species caused by these very different alien invaders. To find out more about the growing problem of invasive speciesand what to do to help contain the problemreturn to this page for additional resources and links.
Story One: U.S. Biologists Seek Ways to Stop Alien Mussel Invasion Go>>
Story Two: Stowaway U.S. Corn Rootworm Eats Its Way Across Europe Go>>
Story Three: Australian Bug Imported to Fight Pesky Plant in U.S. Everglades Go>>
Biological Threats Posed by Non-Native Species in the United States National Geographic Today producer Chad Cohen spent more than two months investigating the biological threats posed by non-native species in the United States. Read the three-part series on his investigation. Go>>
Are Bugs Fighting Back in the Evolutionary War on Humans? Humans are accelerating evolution in species ranging from viruses and bacteria to agricultural pests. The consequencessuch as drug-resistant pathogens, and insecticide- and herbicide-resistant insects and weedsare costing at least $50 billion per year in the United States alone. It's an escalating war that requires every weapon in the human arsenal. National Geographic Today's Bijal P. Trivedi reports. Go>>
The World Conservation Union: Invasive Species Specialist Group
Invasivespecies.gov is the gateway to U.S. federal efforts concerning invasive species. On this site you can learn about the impacts of invasive species and the federal government's response, as well as read select species profiles and find links to agencies and organizations dealing with invasive species issues. Invasivespecies.gov is also the website for the National Invasive Species Council, which coordinates federal responses to the problem.
U.S. Fish and Wildlife Service Invasive Species Program
Ecological Society of America: Invasive Species Fact Sheet
The Nature Conservancy: Invasive Species Links
Invasive species articles from People Land & Water, the employee news magazine of the U.S. Department of the Interior
SOURCES AND RELATED WEB SITES