What is the Difference between Exotic, Nonindigenous, Non-Native, Alien,
Nuisance, and Invasive Species?
In general, these terms all refer to plants, animals, or
microscopic organisms living outside their native range.
Among these terms, the major difference is between
nonindigenous and invasive.
A “nonindigenous” species is an organism (plant, animal,
microbe) found living beyond its historic native range, which
is usually taken as the area where it evolved to its present
form. Executive Order 13112 of February 3, 1999, defined
“alien” species as “any species, including its seeds, eggs,
spores, or other biological material capable of propagating
that species, that is not native” to the particular ecosystem
in which it is found. Thus, alien can be used interchangeably
with nonindigenous. The terms exotic and non-native are
both synonyms for nonindigenous. So nonindigenous =
alien = exotic = non-native.http://www.glerl.noaa.gov/pubs/brochures/inva...