ABSTRACT
Biological invasions are now recognized as one of the most serious forms of environmental degradation on Earth. As humans have increased their movements around the world and have increased global trade, so have they increased the intentional and unintentional distribution of harmful organisms. While most introduced organisms are beneficial for food, fiber, aesthetics, and other uses, some have the potential to cause great harm. The impact of the harmful species has been demonstrated to be an important component of global change (Mooney and Hobbs 2000).
