Invasive Species 101 - An Introduction to Invasive Species


What is an invasive species?

An invasive species is a non-native species (including seeds, eggs, spores, or other propagules) whose introduction causes or is likely to cause economic harm, environmental harm, or harm to human health. The term "invasive" is used for the most aggressive species. These species grow and reproduce rapidly, causing major disturbance to the areas in which they are present.

Things to know about invasive species:

Invasive species, if left uncontrolled, can and will limit land use now and into the future.

The longer we ignore the problem the harder and more expensive the battle for control will become.

Invasive species can decrease your ability to enjoy hunting, fishing, camping, hiking, boating and other outdoor recreational activities.

The United States suffers from $1.1-120 billion per year in economic losses due to exotic, invasive species.1, 2

Approximately 42% of Threatened or Endangered species are at risk due to non-native, invasive species.1



Old world climbing fern

old world climbing fern
Photo by: Peggy Greb, USDA ARS




1 Pimentel, D., Zuniga, R., and D. Morrison. 2005. Update on the environmental and economic cost associated with alien-invasive species in the United States. Ecological Economics 52. pp 273-288.

2 OTA. 1993. Harmful non-indigenous species in the United States. Office of Technology and Assessment, United States Congress, Washington DC.