What can be done about Invasive Species Ecological Society of America 02.01.01 The best way to limit impacts of nonnative species is to prevent them from invading and becoming established in a new area. However, it is difficult to know if a species will become a problem in a given locale and we often don't know why some species become invasive. Sometimes species don't pose problems until years after they've been in an area.     Complete removal may be feasible early in an invasion or in a restricted area, but more often control or containment is the only practical way to limit ecological or economic damage, especially for species that have already invaded large areas. Control methods can include the following or a combination of all four:     Chemical control (using pesticides) can be effectively used to kill invasive species, but it can be problematic due to impacts on non-target organisms (including humans), the development of resistance, and expense.     Mechanical control (physically removing the invasive species) is often successful, but can be expensive and labor intensive.     Biological control (introducing a natural enemy-predator, parasite, or disease-often from the pest's native range) can be an environmentally sound way to control invasive species with minimal expense, but some control agents do not survive and others attack non-target organisms, i.e., become invasive themselves.     Ecological control (manipulating environmental factors such as fire and water flow) can provide native species an edge in competing with invasive species.   Prepared by the Ecology Society of America   1707 H St., NW Suite 400   Washington, DC 20006 ©2001 The Aurora Collection, Inc. All Rights Reserved. Site Development by: Interactive Multimedia. Inc.