The introduction of species into areas outside of their native habitat is a concern for all ecosystems, both terrestrial and aquatic. These non-native introductions occur through a variety of pathways including intentional introductions, accidental releases, and natural events such as hurricanes. The majority of species released into new, non-native areas either are not able to establish within the introduced range, or are able to establish but do not cause significant damage. However, a small percentage of these introductions become established and cause severe environmental and economic damage; these are referred to as invasive species. In the marine environment, accidental release through the ballast water exchange of oceangoing vessels has traditionally been cited as the most likely pathway for marine species MORE