Invasive Species – What Does That Mean?

Invasive species is an insidious issue worldwide. Economic impacts caused by invasive species are estimated to be $1.4 trillion annually – about 5% of the global economy. The U.S. economy alone loses almost $120 billion annually from invasive species. Among the many impacts that invasive species cause, being a threat to imperiled species populations is among the most important. Most biologists agree that habitat destruction is the primary cause for species endangerment followed closely by interactions with invasive species. Invasive species also have been implicated as threatening ecosystem properties that are fundamental to human wellbeing such as secure livelihoods, health, good social relations, security, and freedom. Species declines caused by invasive species are particularly troubling. Gurevitch and Padilla indicate that of 930 total species native to North America that are in decline, 131 were due to predator and herbivore interactions with invasive species and 431 were due to invasive plant competition and indirect habitat losses.