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Home / What are Invasive Species?

What are Invasive Species?

Invasive Species - The Basics
Provides the official definition for what are invasive species and related information.

Invasive species can be plants, animals, and other living organisms (e.g., microbes). To learn more, see our Species Profiles which provides general information about species considered to be invasive.

See also: Invasive Species 101 resources

What Defines an Invasive Species?

As per Executive Order 13112 (Section 1. Definitions) an "invasive species" is a species that is:

1) non-native (or alien) to the ecosystem under consideration and,

2) whose introduction causes or is likely to cause economic or environmental harm or harm to human health.

See also:

How are Invasives Species Spread?

Invasive species can be introduced to an area by ship ballast water, firewood, accidental release, and by people. Human actions are the primary means of invasive species introductions. See our Pathways page to learn more about how invasive species are introduced to new areas.

What are the Impacts of Invasive Species?

Invasive species can lead to the extinction of native plants and animals, destroy biodiversity, and permanently alter habitats. See our impacts section to learn more about the various impacts of invasive species -- economic and social, environmental and ecological, and human health.