Definitions of Terms ¹

Aquatic Species

All animals and plants, including pathogens or parasites of aquatic animals or plants, that are dependent on aquatic ecosystems for at least a portion of their life cycles.

Alien

Synonymous with "exotic," a species that is not native to the continental United States.

Established species

A species with one or several reproducing, self-sustaining populations in open ecosystems.

Ecosystem

A community of organisms and their physical environment that interact as an ecological unit; it includes human environments and elements of the infrastructure such as climate, geographic latitude, altitude, and soil type.

Exotic

An organism or species that is not native to the continental United States; synonymous with "alien."

Immigration

The move--including the unintentional introduction by humans--of an individual, group, or species into a geographical area.

Impact

Any change to an ecosysten either natural or made by humans, either harmful or beneficial.

Importation

The act of bringing an organism from a foreign place or country into another country.

Introduction

The release or escape of a nonindigenous species into a geographical region or into an ecosystem where it did not previously exist.

Nonindigenous

A species or other viable biological material that is not native to an ecosystem or to a geographical region; includes exotic and transplanted species.

Nuisance species

A species potentially injurious to humans, fish, or wildlife or their habitats, or to the interests of agriculture, horticulture or forestry in the United States.

Any species that threatens the diversity or abundance of native species or the ecological stability of the infected ecosystem or interfers with commercial, agricultural, aquacultural, or recreational activities.

Pathway

The means by which species are transported into a geographical region or into an ecosystem.

Pest species

Term synonymous with nuisance species.

Species

A group of organisms that is formally recognized as distinct from other groups; also a taxon of the rank of species, i.e., a category below genus.

Transplants

Individuals of native species of North America that since European colonization were introduced into ecosystems outside their historic ranges.