Invasive Species

The emerald ash borer (EAB), a species native to Asia, apparently arrived in North America in ash wood used for shipping purposes. Discovered in Michigan in 2002, this invasive species is highly destructive to North American ash trees. The arrival and spread of these beetles has prompted many states and provinces to set up EAB programs to protect their ash trees and the ecosystems that depend upon them.

An invasive species is a species that has been introduced to an area outside of its native habitat, where it can have negative ecological, economic or human health impacts. Infamous examples include Burmese pythons, kudzu, and gypsy moths. Invasive species are frequently generalists in terms of food, or habitat needs, have fewer predators in their introduced environments, and are better able to exploit disturbances than their native competitors. Climate change and its impacts will lead to more disturbances, and thus may further facilitate the establishment and spread of invasive species.

As with native species, changing climatic variables can lead to range shifts and expansion of invasives. Severe weather events involving flooding, high winds, and habitat disturbance may damage native systems, opening the door to invasive species. Invasive species may also exacerbate ecosystem transformation driven by other climatic variables such as changing fire regimes and ocean acidification. The ways that humans choose to adapt to climate change may also increase the risks of invasive species by creating new pathways of introduction. Finally, the efficacy of current management tools and strategies used to prevent and control invasive species will need to be re-evaluated in the face of a changing climate.

Abridged from the report National Fish, Wildlife, and Plants Climate Adaptation Strategy, Chapter 2, Section 2: “Existing Stressors on Fish, Wildlife, and Plants."