In the broadest sense, invasive species are those which were “artificially” introduced into an ecosystem, either intentionally as “exotic” ornamentals, or inadvertently via passive seed transport through international travel and commerce. The problem results when invasives thrive to the detriment of native species, in some cases completely wiping out the natives. This dominance is frequently the result of certain traits that give the invasive an advantage over natives, freequently:
- Production of many offspring
- Early and rapid development
- High tolerance and adaptability to many environmental conditions
- Genetic resistance to local fauna and diseases
The negative impact of invasives is far-reaching. Studies show that invasives can reduce
natural diversity, impact endangered or threatened species, reduce wildlife
habitat, create water quality impacts, stress and reduce forest and agricultural
crop production, damage personal property, and cause health problems.*
*Source: New Hampshire Department of Agriculture, Markets & Food
Terrestrial Invasive Plant Species, “Guide to Invasive Upland Plant Species in New Hampshire”