No, it's not Hollywood's latest thriller, but a real threat to our environment and economy. Increasing human population and per capita consumption, leading to expansion of global trade, and increases in human mobility have resulted in unprecedented invasion by nonnative species. These biological invasions produce severe, often irreversible impacts on agriculture, recreation, and our natural resources.
Invasive species threaten biodiversity, habitat quality, and ecosystem function.
Introduced species also present an ever-increasing threat to food and fiber production. In the United States, the economic costs of nonnative species invasions reach billions of dollars each year. Whether they are called invasive, nonnative, alien, exotic, or nonindigenous, introduced species are those that evolved elsewhere and have been purposely or accidentally relocated . Introduced species often find no natural enemies in their new habitat and therefore spread easily and quickly. Some agricultural crops and trees have escaped plantations and become pests, and the importation of agricultural and forestry products has brought assorted pest species and diseases into new areas.