What is the difference between invasive, exotic, and non-native species?

Exotic and non-native basically mean the same thing. An organism is considered non-native or exotic if it is found in an ecosystem where it did not evolve. A large percentage of the food we produce in this country comes from non-native species. The majority of non-native species never causes a problem. Unfortunately, the few that do cause problems more than make up for the rest of them. This small percentage of non-native species causes a tremendous amount of harm to our native habitats and the plants and animals that inhabit them; to natural areas such as forests, lakes, and rivers that we use for recreation; to agriculture; to our economy; and directly to humans. These harmful exotic or non-native species are called invasive.

Jeremy Greene, Clemson University, bugwood.org United States Environmental Protection Agency Great Lakes National Program Office, USEPA, bugwood.org

Below are links to some websites that have useful information on invasive species:

Center for Invasive Species and Ecosystem Health

National Invasive Species Information Center

Invasive Species Advisory Committee – Invasive Species Definition Clarification and Guidance White Paper